CHAPTER 7 - WWII JAPANESE MILITARY TACTICS - SECTION 1
1. GENERAL.
The basic tactical principles of the Japanese army have been derived from careful study of the techniques of foreign armies and considerable experience in combat against major military forces on many kinds of terrain. The variations in Japanese tactics from those of modern armies lie in their application of principles to particular tactical situations rather than in the general doctrine that governs their operations. Their tactical principles are relatively sound by present day standards. However, from their performance in the field, their practice does not measure up to their doctrine. The Japanese have given an excessively aggressive interpretation to their basically reasonable foctrine, and, in addition, apply this interpreted doctrine in a still more aggressive manner.
Japanese forces have fought tank actions in the plains of Manchuria and mountain battles in Central and Southern China. They have executed successful landings; defended strongly, though unsuccessfully, against Allied amphibious operations; demonstrated a considerable ability as jungle fighters; and, in Manchuria and China, implemented effectively fundamental principles of open warfare, although this was done against an inadequately equipped and under-trained enemy. By and large, Japanese tactics have been based in effective organization, training, and equipment of their troops for fighting in areas in which it was expected they would operate, and against opponents it was believed the would meet. Their ability to make tactical modifications has been found to be limited and slow.
The Japanese lay great stress on offensive actions, surprise, and rapidity of movement with all commanders and staffs operating well forward to keep themselves constantly informed of the situation. Their tactical doctrine is based on the principle that a simple plan, carried through with power and determination, coupled with speed of maneuver, will so disrupt the plans of hostile forces that success will be assured. COmbat orders, in both attack and defense, from the highest to the lowest unit invariably carry the admonition that the "enemy forces will be annihilated". Surprise is an ever present element, while the enevelopment is the preferred form of attack. horough reconnaissance is also taught, and the practice of infiltration is greatly stressed. The Japanese willingness to attack a position, with forces which other nations would consider to be insufficient for the task, is based on the assumption of their so called military supriority.
To Japanese officers, consideration of face and toughness are most important, and they are threfore prone to paper heroics. They have shown considerable boldness against superior forces as well as against poorly equipped troops; however, confronted now by first class, well equipped forces, they have began to adopt more circumspect methods.
Despite the opportunities presented in over 7 years of active combat, the Japanese have continued to violate certain fundamental principles of accepted tactics and technique. Their tendency to persist in such violation apparently has been based primarily upon a failure to credit the enemy with good judgement and equal military efficiency. Recent operations have indicated an ability to profit by experience, but the extent to which performance can be brought to correspond to the lessons learned still remains questionable.
2. MOBILITY, SURPRISE, AND OFFENSIVE ACTION.
Successes won by the Japanese army in the early stages of the war are not attributable to new techniques of land warfare. On the contrary, they resulted from efficient, resolute application of the classic principles of mobility, surprise, and offensive action. Japanese tactical doctrine holds that a simple plan, carried out with surprise, poser, determination, and speed will disorganize the enemy and lead to quick and overwhelming victory, defined by the Japanese as the annihilation of hostile forces.
Mobility, the first basic principle emphasized by Japanese tactics, has not been achieved by an extensive mechanization. The Japanese planned to fight where mechanization would be a decided liability, particularly in the jungle areas of Southeast Asia and the Southwest Pacific. Therefore, they developed mobility by exploiting the marching ability and stamina of the trained Japanese infantryman, by curtailment of supply trains, and by utilization of equipment designed to go wherever the infantryman goes.
Surprise is the basic second principle of Japanese tactics, and its attainment is allied closely to mobility. Through rapid movement, often over so called impassible terrain, and under weather conditions which we normally would believe unsuitable for offensive operations, the Japanese have been able to achieve tactical surprise in many operations. This surprise has been implemented further by a quick deployment and sudden attack. As their operations have shifted form the strategic offensive to the defensive, the Japanese have been less able to carry out the maneuvers necessary to the accomplishment of this active form of surprise. They continue, nevertheless, to exploit the forms of surprise that are compatible with defensive operations such as ambush, camouflage, ruses and deceptions, the subersive work of fifth columnists and the use of various forms of suicide missions.
The third basic principle of Japanese tactics is offensive action. No matter what the situation, a Japanese commander's first reactions to it is tp act aggressively to maintain the traditions of his army. It does not follow that such offensive action is not well planned; granted sufficient time and a situation which fits a preconceived pattern, it usually is. However, the orders which implement these plans usually are not as clear or detailed as is necessary, and they generally are more aggressive in tone than conditions warrant.
in addition, it is true that the active offensive may be assumed when a more passive form of action might improve the possibility of a successful outcome of the operation. While an over emphasis undoubtedly has been placed on the need for aggressive action, many of the victories of the Japanese army can be described to a devotion to this principle. Igt is a factor with which our forces must reckon at all times and one which may increase considerably the military potential of any body of Japanese troops.
Even when the Japanese commander assumes the defensive, he will, so fas as possible, carry out teht defense by using the most aggressive tactics that the situation permits. such offensive methods may not change the final outcome of the defensive operation in question, and may even shorten it as compared with the time that would be required to defeat a more orthodox foe. Yet, aggressive action, combined with a firm determination to die rather than surrender, make the Japanese both dangerous and stubborn opponents.
3. SOURCES OF TACTICAL INFORMATION.
The Japanese have not operated against a modern army in relatively open country, except for the border clashes with the Russians at Changkufeng in 1938 and at Nomonhon in 1939. Therefore any study of their basic doctrine must depend, to a large extent, on such sources as their field manuals, reports of field maneuvers, service school problems, and training directives. Certain principles cab be deduced from their operations against the Chinese , but these campaigns are not comparable with those of the European war, and casre must be taken in the derivation of principles from them.
4. TACTICAL ADJUSTMENT TO OPEN TERRAIN WARFARE.
The tactical comsequences of the shift from jungle warfare to small island defense to operations in country that affords adequte opportunity for maneuver as well as for large scale, combined employment of artillery and armor will be of the utmost importance. The Japanese have refused to accept their opportunities to fight on open terrain against an American army on the central Plain of Luzon or a British army in Central Burma. They withdrew from the plain and confined their major operations to rugged jungle country and tghe city of Manila so far as it was possible to do so.
This may indicate what the Japanese would prefer to do on the mainland of Asia or on their home islands. But, as the areas of open terrain grow larger, the possibility of doing all their fighting on rough ground or in the cities will diminish, and some tactical program will have to be employed by the Japanese. The pronblem they face is not easily solved. such weaknesses as defects in Japanese tanks and the inferiority of their artillery, not only in numbers and quality but in methods of employment as well, will be far more heavily felt.
The Japanese have had ample time in which to study the tactics of European armies and have had access to German designs. To a limited extent they have ahd the chance to examine British, Amrican, and Russian equipment. But the burden of developing new models and new techniques of employing them, while maintaining an adequate level of production of existing designs, appears to have been beyond the capacity of the Japanese industry and the Japanese army. Neverheless, certain lessons, such as the impossibility of deiending a beach under concentrated air and naval bombardment, have been learned by the Japanese and applied with increasing effectivemess as operations approach closer to the home islands. such improvement in Japanese tacticcs has not been rapid nor complete enough, however, to promise an eradiction of the majority of the tactical errors to be noted in this chapter.
Certain modifications in Japanese tactical methods, in training, and in equipment will make difficult the readjustment of Japanese units from jungle to open terrain warfare. Mobility, attained by curtailment of supply trains and adoption of light equipment, already largely neutralized by the Allies even in the jungle, will tell hevily against the Japanese when Allied motorized equipment can be used on a full scale as it was in the central plain of Luzon.
Tactical surprise will be far more difficult for Japanese commanders to achieve in areas of better visibility, particularly under Allied air superiority. Even in country that afforded ample natural concealment, emphasis upon surprise gained by speed of movement, deployment, and attack at times has induced Japanese officers to commit their forces to offensive efforts without adequate reconnaissance. In open terrain, where better road nets are available and large scale coordinated actions feasible, rapid shifting of Allied reserves to meet Japanese attacks will be possible, and the consequences of am unreconnoitered Japanese offensive will be more serious than they have been in jungle terrain.
A shift from jungle to more open country is not likely to reduce the Japanese commander's desire for offensive action. But the penaltiues of an unsuccessful attack in open terrain are much more heavy than in an area of dense vegetation where troops, wrongly committed, can be withdrawn with relative ease. Whether the Japanese attack is preceded by adequate reconnaissance or not, it often is launched without sufficient force to carry it through to a successful conclusion. This mistake will be more expensive to them the more open the ground on thich they fight.
5. COMPOSITION AND EQUIPMENT OF COMBAT UNITS.
As in modern armies, the Japanese division is the basic unit of the combined arms. Two or more divisions, or equivalent units, and the necessary auxiliary troops are combined to form an army. Japanese armies are approximately the same as corps in other armies except that, in addition to the normal tactical functions of that organization, they have supply and administrative duties as well. Armies generally are designated by number, and two or more of them may be grouped to form an area army (comparable to an Allied army) with the addition of the necessary reinforcements of area army troops. Finally, a number of area armies may be placed under the control of a main area army which functions as the equivalent of an Allied theater of operations.
The limited number of Japanese armored divisions have prevented the function of armored armies although such formations were projected in theory. As conditions now obtain, they are attached to armies or area armies in the regions in which it is contemplated that they will be used.
Tactically, the Japanese infantry division is far less capable of effective operation than are its Allied counterparts. It is stronger in personnel than the corresponding American, British or Rusisan units, but it does not contain the fore power of such an Allied unit. The stroonger of the two general types of Japanese divisions is given 12 75-mm guns, 24 105-mm howitzers, and 12 150-mm howitzers to which other artillery may be attached as the situation requires. This attached artillery appears to be theoretical only. In number, caliber, range, and weight of projectile of pieces these figures compare well with the 36 105-mm ans 12 155-mm howitzers of the American division artillery and the 72 25 pounders (88 mm) of the British division. However, these strengthened divisions are rare in the Japanese army, and more has been met in the field. The artillery armament of the standard division is 36 75-mm guns only. This armament is in no way comparable to that of the Allied divisions, and is seldom, if ever, reinforced from higher echelon in the same degree as the Allied division.
The rifle furnished to the Japanese infantryman is a manually operated, bolt action weapon which cannot produce the sustained fire power of the American semiautomatic weapon. The machine guns and mortars assigned or attached to the infantry are about as effective as those given to Allied units. The supporting antitank and infantry guns are supplied in far smaller numbers and calibers than those in Allied units.
The transport of the Japanese division is far weaker than that of Allied counterparts for movement in normal open terrain. However, it is better adapted to movement in rugged areas, deficient in roads and bridges.
Tank units are attached to the infantry division but far less frequently than in Allied armies operating in the Pacific. The tanks with which these units are required are equipped are far less well armored and have much less fire power than those of United Nations forces. Primarily these tank units are used in counterattack roles and as dug-in but mobile pillboxes in defense of towns and rugged terrain. Their employment in cooperation with infantry has been consistently weak.
Japanese armored divisions are equipped with tanks that are far weaker in armor and armament than comparable Allied formations. The artillery with which they are supplied lacks both mobility and fire power, vis-a-vis Allied armored artillery. The ratio of infantry to tanks is low, being about nine infantrymen to one tank as compared with 13 to one in the American armored division and about 30 to one in the Russian tank corps. The lack of adequate signal communications in the tank units of the division limits their operational efficiency.
6. EMPLOYMENT OF COMBAT UNITS.
In large scale operations, the Japanese use the division as the tactical unit of measure, and mission type orders are issued to govern the tasks of such units. Since the early days of the war, the only Japanese offensive of any size against a modern army has been in the Kohima Imphal campaign in manipur in the spring of 1944. In this operation, three Japanese divisions were employed under the overall direction of the 15th army, to each of which a definite mission, was assigned. These missions, however, were not closely tied-in with each other and prescribed what must have been only the preliminary objectives of he operation. There was no provision for cooperation between the divisions, and the possibility of reinforcement from one unit to another was small. The Japanese seemed to rely on the course of events to determine what future moves would be. It is quite certain that the plan ignored possible British reactions except that of withdrawal, and the Japanese depended on this retreat to solve their logistical difficulties.
On the defense, on the other hand, the Japanese have been able to organize rather large forces into units which can depend strongly on favorable terrain. Many examples of such operations are available, and it can be said with certainty that they are far more effective in their small unit defensive tactics than in the overall direction of the defense of a large area. Cooperation between adjacent units of all sizes is poor, and logistical arrangements are not sound. Defensive positions are organized by units of any size, with the polsitions of smaller units usually being better sited than those of larger ones.
In both offensive and deffensive operations, the Japanese are great believers in the task force principle, and it is difficult to say what unit they consider as the basic one in the employment of large or small units. In the Manipur operation, the forces organized varied from an infantry regiment, reinforced by tanks, mortars, artillery and engineers to an infantry battalion, less a company but with attached artillery. Small flying columns were made up of units as small as company less a platoon. In coordinated operations, the basic unit may be the battalion. IN any operation, there is a definite tendency to commit forces piecemeal and to attempt to retrieve a failure by the employment of anoter unit of the same size of by the re-use of the unit already repulsed.
In small unit operations, the basic offensive unit appears to be the platoon, but the communication means are so poor that the platoon commander loses most of his conntrol over his squads once they have entered combat.
In defensive operations the main principles governing employment seem to be the size of the area to be defended and the force available. The basic large unit appears to be the battalion, while small unit defense is carried out on the platoon level.
Ths far the outstanding individual and collective characteristic of the Japanese soldier has been his refusal surrender, even when the situation is hopeless from a military point of view. Japanese troops have willingly died in pillboxes, caves, or in wild banzai charges when deathmight have been avoided by surrender or flight. Such conduct in battle has increased greatly the time and cost in men and materiel of the campaigns conducted against the Japanese, and its basis continues to be the high morale of the Japanese soldier, even under the most unfavorable conditions. No appraisal of Japanese tactics is valid that fails to take account of this almost fanatical battlefield morale because of which half dead Japanese soldiers express their gratitude for their Emperor for the privilege of dying in his cause and commit suicide rather than be taken prisoner. Three of the fundamentally important bases of this battlefield morale are belief in the invincibility of Japan, a faith in the need for the supremacy of the state over the individual, and a complete trust in the infallibility of the divine will of the Emperor.
These concepts are acquired long before the soldier reches the army; he learns them at home as a child and is taught them in school as a boy. They are so much a part of each Japanese that he never feels a doubt of their truth. These beliefs do not make the Japanese a superman, but they do provide a sound base for the building of an army firmly convinced of the soundness of a doctrine of offensive action and of the necessity of death rather than surreder. It is this high morale that has enabled the Japanese high command to plan operations that depend on a willingness of the troops to push their attcks to a successful conclusion regardless of losses, or to endure defensive combat under literally bestial condition with no prospect of escape or relief.
Nevertheless, the bases of Japanese morale are subject to attack. To maintain a belief in the invincibility of Japan and the divine will of the Emperor requires that the army be victorious in practically all it undertakes and that the decisdons handed down in the name of the Emperor be sound. These two requirements are being met less and less fully, and it is quite possible that the time will come when this is apparent even to the least educated private soldier. How great the effect of such a discovery will be on the morale of Japanese soldiers acnnot be predicted with certainty, but their morale undoubtedly will deteriorate markedly. Such a break in morale would correspondingly reduce the effectiveness of Japanese tactics by removing the base on which they depend.
1. COMMAND DOCTRINE.
The doctrines that govern the exercise of command in the American and Japanese armies are quite similar. The Japanese are just as firmly convinced of the value and need of a staff to assist the commander in the discharge of his various duties as we are. In actual practice, the Chief of Staff of a Japanese division or higher unit has more to say as to the direction of the formation than does his counterpart in an equivalent American unit. This is partly attributable to the fact that the division or higher commander is a direct Imperial appointee and, as such, must be protected from the blame for such mistakes as may occur in the operation of the command.
The chain of command follows a pattern similar to that of the American Army, and the by-passing of links in that chain also is discouraged. The staff, except for the Chief of Staff, is given authority to issue orders without prior approval only in very special circumstances. It assists the commander in his estimate of the situation and in preparing, disseminating, and supervising the execution of orders to subordinate units. Emphasis is placed on the necessity of the commander being as well forward as possible and on his being in close contact with his special staff officers.
Infantry officers are told to be as near the front lines as the situation allows, not only to control the action but also to encourage the troops by their example. In the Japanese Army, the other arms are attached more often to the infantry than they would be in our Army While the principle of support is well established, it is less often employed than it is by us, and a distinction between direct and general support is seldom made and less often actually used.
2. FIELD ORDERS.
a. General.
Japanese field orders follow a form very similiar to the American field orders and are generally brief. On many occasions, however, clarity is sacrificed for brevity, with the result that the recipient is in doubt as to details of his own m1ssion, that of supporting units on his flanks and rear, or the general enemy situation. In some instances, orders are verbose, yet do not cover those essentials necessary for a complete field order.
Military abbreviations and map coordinates are not used. Paragraphs are numbered consecutively with a separate paragraph used for each new subject or new unit mentioned in the order. Security precautions are haphazard, or seldom taken to insure protection against compromising the contents of the order. Reference is rarely made to frontages, zones of responsibility, and other similar details found in the field orders of other modern armies. The Japanese make use of fragmentary orders, especially in instructions to the arms and services which are to support the main attack. These include orders to antiaircraft, transport and communications units, and other supporting elements.
Even in fragmentary orders, Japanese regulations state that all particulars essential to the joint action by the units concerned should be included. When time is short, a fragmentary order will be issued to the commanders concerned, with the complete field order published at a later date.
b. Content of field order.
While the items to be included in a field order will vary, the Japanese field order, according to service regulations, should generally have the following sequence:
(1) The heading of the order. This contains the designation of the issuing unit, the place, and date of issue. Map references are seldom indicated, but geographic designations occur frequently.
(2) The situation with reference to hostile and friendly troops. The information included in this paragraph is usually limited to that which is essential to the subordinate commander.
(3) The plan of the commander. This is generally a brief statement of the decision which is arrived at in order to combat the enemy.
(4) The distribution 0f the troops and the missions assigned to the various units of the command.
(5) Items concerning the mission of supporting arms and services and administrative matter.
(6) Location of the command post and axes of communication.
The distribution of the troops is noted in an annex in the top margin of the order, or in the body of the order itself. Units are usually mentioned in the following order: infantry, armored forces, cavalry, artillery, engineers, aviation, signal units, sanitation troops, and transport units.
3. CONTROL IN COMBAT.
The methods by which the Japanese commander controls his troops in combat are considerably less complete and well thought out than those used in other armies. The Japanese commander in the attack designates definite locations on the ground, such as assembly areas, lines of departure, zones of action, unit boundaries, limiting points, lines of destination (objectives), and directions of main effort to coordinate the operations of subordinate units. However, little or no use appears to be made of phase lines and limiting lines. Lateral boundaries appear neither to run through points easily identified on the ground nor to be supplemented by the assignment of compass directions for the attack. Zones of action probably are not assigned to units smaller than the regiment. No definite information is available to indicate that any use is made of bomb line, nor any other predesignated line to coordinate air operations with those of ground units. The assignment of intermediate objectives and the breaking down of large objectives into smaller ones for subordinate units seem to be neglecled. The rigid sectors assigned to the artillery units of the command constrict their area of operalion and effectively hmit rapid transfer and massing of fires to the flanks of the unit. Time of atlack appears usually to be specified by such phrases as "daybreak," or "after the preparatory fire of the artillery," rather than by a definite day and hour.
In the defense, the Japanese commander divides his position into sectors. which are delimited from the rear of the zone of resistance to the forward edge of the outpost position. The composition of the troops in each sector indicates the plan of thr offensiYP which he expects soon to resume, as well as the location of the expected enemy attack. The location of the forward portion of the defensiYe position is prescribed as are those of the outpost and adYance positions. Beyond these locations, the defensive organization depends on the commanders of the sectors.
In any type of operation, the Japanese commander will find himself with far less control over the combat, once it is joinPd, than a commader of a comparable Allied unit. The main reasons for this lie in the relatively poor quality and obsolescent nature of Japanese signal equipment and the ineffectiveness of the Japanese equivalent of the message center (or signal office). The Japanese place emphasis on the use of wire communication, but they do not extend it down to as low echelons as we do, nor do they supplement iL as well and thoroughly with radio. In smaller units in combat, communication depends largely on runners or signal flags, even in tank units in which the allotment is one radio per platoon. The doctrine that governs the operation of the message center is quite sound, but the strain of actual operations seems usually to confuse the personnel so that their operations are less than satisfactory.
The control that a commander keeps over the course of the battle through the employment of his reserves is not as valuable a tool to the Japanese as it iS to the leaders of other armies. This is caused by the tendency to commit a larger percentage of the total force to the firsl attack and by the dispersion and forward placement of reserves which prevent their use in mass at the decisive moment at the point of greatest opportunity.
1. CONSISTENT TACTICAL WEAKNESSES.
There are many weaknesses in the Japanese application of their tactical principles which will be discussed in detail in the appropriate portions of this chapter. There are certain weaknesses in their basic approach to tactical problems that are reflected in all their operations, and are fundamental to any consideration of their methods. The two main tendencies that handicap any Japanese commander in his own planning and execution are:
(1) an attempt to apply a standard tactical response in any given situation.
(2) as a corollary to this, an inability to imrovise or alter plans in response to changing circumstances. The Japanese concept of predetermined or set combat situations has considerable strength so long as the problems which confront the commander can be solved by the pattern he wishes to apply. The strength proYided by this method is rigid and brittle, however; it breaks easily if the Japanese are unable to dictate in advance the course which the action is to follow.
If the Japanese commander fails to fix the scheme of combat, he of necessity is confronted with an unexpected situation for which he may well have no ingrained reaction. Even if he can apply some precedent to the problem he faces, he has been thrown off balance by the enemy's seizure of the initiative and does not react as quickly to the urgency of the situation as would a commander whose training has stressed the application of an individual solution to each distinct problem. No matter how practiced the leader, if he must search his memory for a solution to a similar situation before he can adjust his plans, he cannot react as quickly as one whose training has been more flexible. The Japanese have recognized the need for the use of initiative by individual commanders, but their system of training has failed to develop it to any great degree, except for those situations in which the commander has been told that he must make his own plan. For example. the commander of a raiding unit is told that he must vary his tactics to fit the conditions he finds on his arrival at his ob objective; he reaches that area with no preconceived plan to apply and, as a result, is Forced to adapt himself to what he finds there.
Even so, the Japanese commander is likely to attempt to adapt some known solution to the problem that faces him. The lessons from this inflexibility in the methods of Japanese commanders are that they must never be allowed to choose the plan of combat; they must be kept off balance; and must be confronted constantly by what is, from their point of view, an unexpected result of the tactical methods they adopt.
2. RECENT TACTICAL TRENDS.
Because the greater part of the Japanese operations, outside of China, has been defensive since the middle of 1942, the trends that are most prominent have been in the defensive phases. For this reason such large scale campaigns as the Manipur operation in India and Burma, in the early months of 1944, stand out more markedly than they would if the Japanese had been engaged in a consistent program of offensive action.
So far, as new developments in offensive action are cOncerned, it appears that the Japanese have learned little from their study of the tactics used in the European war and their observation of the methods employed against them by Allied armies.
Their offensive methods are still those of the Chinese operations, adapted to the different terrain of the southern areas. Their artillery and tank operations have not been modernized greatly in comparison with those used against the Chinese, and their employment of units of the combined arms remains unimpressive.
On the defensive, with which the Japanese have been more directly concerned, on a wider variety of terrain, they have introduced several new tactical methods and improved on the theory and practice of others. Outstanding has been the development of suicidal units of various types, ranging from the air suicide units whose objectives are mainly the larger warships to small parties of three to five men whose mission is the destruction of a single field piece. Another development has been the greatly increased utilization of caves and artificial underground shelters into the use of which the Japanese largely have been forced by the weight and destructiveness of Allied air and naval bombardments.
The technique of the Japanese counterattack has been considerably improved in recent operations; the objectives to be gained and the forces committed, although the numbers employed in most such attacks have been reduced, are more in line with the demands of the situation. Counterattack of our beachheads by seaborne units has been attempted, and, in some instances, may constitute a serious threat to our landings.
Artillery pieces have been used in increasing numbers, but techniques of fire have not been much improved, although more modern theory is known to higher commanders. Antitank measures have been increased both in number and effectiveness, although they are still far from European standards. Defensive organization, particularly on small islands, has been changed for the better, as was especially evident in the battle for Iwo Jima. Yet defensive tactics employed on large islands have not developed noticeably; the tendency to attempt to anticipate the locations of our landings continues to cost the enemy heavily. Strong and organized defense of areas of open terrain has been avoided as far as possible and may indicate that the Japanese plan to do as little fighting as possible on relatively open ground but intend to confine their main efforts to rugged country, wooded regions, and cities.
1. RECONNAISSANCE.
Japanese reconnaissance principles and techniques are basically similar to ours but their application of them is somewhat different. In the main, their methods are sound, but their results usually suffer from an insufficient allotment of time for reconnaissance and from excessive dependence on native agents practically untrained in military subjects. Sound training does not appear to be the rule among Japanese intelligence officers, and evaluation of the information obtained is often weak.
When military personnel are used on reconnaissance or combat patrols, their work usually is good. Their aggressive activity has consistently obtained information of the disposition of forward enemy troops, defenses, armament, and equipment. As a general rule, Japanese combat intelligence is proficient in static, concrete matters, such as dispositions in forward areas and locations of roads. But it is inefficient in dynamic and intangible information that requires constant collation and analysis, such as order of battle and enemy capabilities.
The Japanese divide reconnaissance missions into two classes: those that aim at deep penetration of enemy lines and those that attempt only short-distance infiltration. Units carrying out deep penetration missions are designated "reconnaissance parties" and are dispatched by all formations from area armies down to include independent battalions. Such "reconnaissance parties," varying in size with the unit sending them out and with details of the mission assigned, are composed of army personnel, civilian Japanese employees, and native agents. Their emphasis is upon the reconnaissance of enemy rear areas, particularly supply concentrations, troop reserves, and defenses located therein.
They also collect information about the forward areas both on the way in and the way out. The army personnel of "reconnaissance parties" usually come from cavalry or mechanized units. These "reconnaissance parties" should not be confused with the reconnaissance units of the infantry or armored divisions which are designed to fight for their information, while the "reconnaissance party," though armed, fights only when it cannot be avoided. Aerial photography is carried out by units of the Air Force, and this is supplemented by visual observation as the situation requires and permits.
To complete the gathering of combat infonnation, the Japanese use combat and reconnaissance patrols, drawn mainly from the infantry and engineers, to carry out the usual close-range reconoitering of the enemy. Prior to any reconnaissance operations, the personnel to be employed carefully study the available maps and aerial photos to determine routes of movement and objectives to be examined. The troops who compose the parties are trained in the technique of unobserved movement and of sudden combat. Their reports usually suffer from the almost universal Japanese desire to gain face by exaggeration of the results obtained and the damage clone the enemy. Officer patrols are used more commonly than in our army, and the result of this is usually a very aggressive type of operation, even though the mission might be accomplished more effectively without fighting.
2. COUNTERRECONNAISSANCE AND SECURITY.
The Japanese do not seem to have a proper understanding of the means of attaining security for operations, and its value in assuring their successful outcome. So far as counterreconnaissance measures are concerned, the Japanese believe in aggressive action to prevent successful enemy reconnaissance, but tend to rely on their own offensive action to prevent the enemy from reconnoitering their movements and dispositions.
In the more passive field of security, their forward troops are security conscious. They excellently conceal their positions and presence from enemy observation and maintain excellent fire and movement discipline. In rear areas and during movement, however, security has been less good; the Japanese have shown themselves vulnerable to surprise, particularly by units that have infiltrated through forward Japanese positions or moved around their advance or flank guards. The fault is fundamental, for the Japanese feel that security is best attained by a continued pressure against the enemy which presumably prevents his operating against their flanks or rear.
Exaimination of captured documents and the interrogation of prisoners of war have not yielded any great return to the Japanese thus far, partly because of a neglect of opportunities and partly because of poor application of sound instructions to intelligence officers in the lower echelons.
1. GENERAL.
Japanese tactical doctrine insists vigorously on the inherent superiority of the offensive. The object of all maneuver is to close quickly with the enemy where the assumed Japanese predominance in close combat can be realized to the utmost. The ]apanese Field Service Regulations state that the offensive should be taken resolutely, except when to do otherwise is completely unavoidable. Even when the enemy strength is markedly greater, or when the Japanese commander has been placed temporarily on the defensive he is to use every effort to resume the attack and gain the initiative.
The Japanese seem to feel that there is some mystic virtue in the assault, and that defensive combat is a negative form of action unworthy of the Imperial Army. Even though the Japanese are strategically on the defensive, the offensive principle still is strongly emphasized in their tactics. As a result of such training and a resultant faith in the offensive, Japanese commanders often reach decisions to attack where, by all orthodox applications of tactical principles, the defense patently is required.
Their teachings have been found to place very little emphasis on time and space factors, with the result that a concentration of effort frequently is impossible, even if it is attempted. The commander, in his eagerness to retain the initiative and demonstrate his aggressiveness, frequently fails to appreciate the importance of the correct employment of the other arms in conjunction with the infantry and, thereby, loses the opportunity to press home a decisive attack in proper all-around strength at the right time.
ln the discussion of offensive tactics that follows, the usual level of command will be the division. Smaller and larger unit tactics will be discussed when it is necessary for clarity of presentation.
2. APPROACH MARCH.
a. General.
The formations in the advance in day or night movements, similar to those used by other armies, are governed by the same considerations. Parallel colmnus, each self-contained, are usual, unless precluded by the road net.
When the enemy is strong in aviation and mechanized units, long columns are broken up into short serials containing antiaircraft and antitank weapons. Each main column is preceded by an advance guard, while the division reconnaissance or cavalry unit, if present, usually acts as a reconnaissance screen in front of the advance guards.
In addition to the above, there is a notable tendency for the division commander to send forward a mobile detachment in advance of the division, composed of all or part of the division cavalry or mechanized reconnaissance unit, some motorized infantry and engineers, and a small unit of artillery.
This may be in addition to, or take the place of, the reconnaissance screen. It is used for one of the following purposes:
(l) to cover a night march to the probable battlefield where the division expects to enter combat shortly after daylight,
(2) to seize a vital terrain feature forward of the division,
(3) to execute demolitions and so hamper enemy movement,
(4) to execute surprise attacks against the enemy in march formation.
The strength of the detachment pushed forward usually will be greater, if the ultimate mission is defensive, to insure occupation of the desired position in sufficient strength. As contact becomes imminent, the division commander modifies the main formation, as needed, to facilitate the entry of the division into action, with a view to enveloping one or both flanks of the enemy.
b. Advance in two columns.
Advance in two columns is the favored doctrine of the Japanese, although one or three column advances also may be utilized, depending upon the nature of the terrain, the road net, and the proximity of the enemy. The one-column advance is avoided whenever possible, because of the delay in deploying.
In a two colunm advance, it would seem reasonable to have the advance guard under the control of the force commander. In the Japanese division, however, the commander controls only the advance guard of that column wilh which he normally marches, while the advance guard of the other Column is organized and controlled by the commander of that column.
In a three column advance the commader general is in direct command of the strongest column, but has little control over the other two columns. As a consequence of this lack of a single command of the advance guards, there is no integrated control of the advancing force, with the inescapable incomplPle coYerage and weakness of protection which such a deficiency entails. Nor. for that matter, is it at all clear how the Japanese expect the division commander to coordinate the advance of the other column with that of the column immediately under his control.
The advance guard usually constitutes about one-third the total force, but when a meeting engagement is considered imminent it may comprise as much as one-half.
c. Transport and trains.
The division transport and trains normally follow the main columns of the division under division conlrol in the following order: advance section of the transport regiment, unit trains, and the remainder of the transport regiment. Distances helween these units are normally from l to 2.5 miles. The massed trains are under a single commander, designated by the division commander.
d. Attachments.
Units of light and medium artillery, anliairraft arlillery, observation aviation, antitank units, and other arms frequently are attached to a division in the advance.
e. Antiaircraft protection on the march.
For the advance, each front-line division may have attached an antiaircraft organization, but actual reports of such attachment are lacking. This unit, often motorized, moves by 1eapfrogging to critical points along the axis of the division's advance. The guns go into position during such periods as the noonday halt, while the division passes defiles, and while it is in bivouac. If possible, antiaircraft units move forward by roads not used by the other elements of the division. The effective radius of action of one company of 75-mm antiaircraft artillery is considered to be 6,800 yards.
f. Antitank protection on the march.
In areas where there is a threat of enemy tank action against a column, the Japanese, in theory, usually hold some tanks in readiness for employinent against hostile tank forces. Experience, however, has shown that they avoid such clashes, except in isolated instances when the situation is desperate.
Active reconnaissance by both air and cavalry units warns the division commander of impending hostile tank action. Antiaircraft artillery may at times be employed to supplement normal antitank protection measures.
g. Preliminary preparation for combat.
The formation of the advancing division contains the germ of the maneuver which the division commander expects to adopt if he encounters the enemy on the march. When the hostile force is reported approaching from a considerable distance, the division commander estimates where the battle will occur and communicates to his subordinates the general plan of maneuver which he expects to adopt, taking into consideration use of terrain which the enemy considers generally impassable.
He indicates time and place for the delivery of reports and designates a message dropping ground for the air service. His artillery and engineer commanders receive technical information from their own patrols marching with the advance guard and reconnaissance detachment. As contact becomes imminent, the division commander, hitherto marching at the head of the main body of the principal column, moves forward on personal reconnaisance, accompanied by appropriate staff officers.
An advance message center may be designated behind the advance guard, one of the important functions of which is to facilitate collection and dissemination of enemy information.
From his personal reconnaissance and the reports of his reconnaissance agencies, the division commander determines the area in which the division will make its decisive effort, the plan of maneuver, and the location of the division command post. He then issues fragmentary operational orders to initiate deployment of the division. Japanese Combat Regulations warn against waiting for over-detailed information before reaching a decision, and this injunction seems to authorize a very short reconnaissance phase at this point.
3. DEPLOYMENT PRIOR TO COMBAT.
a. Actions of the advance guard.
The advance guard of the column directly under the control of the division commander protects the deployment, either by offensive or defensive methods, and attacks when necessary to obtain important terrain features. Its commander is expected to exercise initiative and boldness of action in specific cases. He obtains the necessary information hy vigorous patroling and, if necessary, by a small scale attack.
Left to his own devices, however, the advance-guard commander usually elects to drive headlong into the advancing enemy, unless specifically restrained by division order.
As the advance guard closes to contact, its artillery prepares to furnish continuous support by leapfrogging from position to position in rear of the infantry. Normal artillery missions are to interdict or harass the movement of enemy columns, to support the action of the advance-guard infantry, and to perform limited counterbattery missions. Extreme ranges for interdiction by 75's are given as 7,500 to 9,000 yards, but in practice missions are seldom fired at over 5,500 yards.
Positions are chosen with a view to supporting the entire attack of the main body from that area. The advance guard artillery reverts to the control of the artillery commander at the time of the attack of the main body. The security detachments in advance of other columns are for their local protection only.
b. Actions of the main body.
(1) Deployment.
In his basic decision for the deployment of his division, the commander determines whether it will be coordinated or piecemeal. The basis for this decision is found in the Japanese Combat Regulations, a translation of which reads: "The division commander, in order to profit by or to extend an advantage won by the advance guard, may have to commit to combat each march column and each element of the main body successively upon arrival. However, if the situation permits, the division commander should seek the coordinated entry into action of his units, in which case he orders the deploym ent of each unit, establishes close cooperation between infantry and artillery, and coordinates the time of the infantry attack."
The question of making a piecemeal or coordinated attack thus appears to be decided largely by the success of the advance-guard action. In map problems studied, the piecemeal engagement of all or part of a force often is justified by the necessity of seizing some prominent terrain feature or by the desire to get out of a defile. The object of the piecemeal attack is to take advantage of a sudden opportunity, while the coordinated attack aims at securing the most effective use of the combined arms at the expense of time.
(2)Coordinated deployment.
As indicated above, the Japanese prefer a coordiriated development "if the situation permits." The measures taken by the division commander to secure this coordination are:
- the assignment of a line of departure (tenkaisen) behind which the major units of his command are to deploy for the attack;
- detailed arrangements to assure coordination between the artillery and the infantry;
- announcement of an hour of crossing the line of departure.
The line of departure is usually an extension of the line held by the advance guard. If the enemy has secured the advantage of priority in deployment, the main body of the division may endeavor to escape a threatened envelopment or premature engagement against superior numbers by deployment along a line behind the advance guard or to the flank and rear thereof.
In the event the deployment is to the flank and rear, the advance guard supported by all the division artillery covers the deployment and delays the advance of the enemy. If the enemy, in anticipation of a collision with the Japanese troops, assumes the defensive, the deployment is modified to resemble the relatively cautious procedure of the attack of a position.
In this event also the division commander tries to develop and attack on the same day to avoid giving the enemy time to improve his position. The phase of the passage from march column to complete deployment is indicated by the following nomenclature used in Japanese regulations: (It must be realized that the following definitions are the translation of the Japanese and do not necessarily bear the same connotations in the Allied terminology.)
Bunshin. Breaking from march column into small columns out of hostile artillery range at the beginning of the approach march.
Tenkai. Deployment along a line of departure (tenkaisen) with a view to performing an assigned combat mission.
Sokai. Advance from the tenkaisen in small (squad or section) columns.
Sankai. Final deployment 0f front-line units to permit firing during the last few hundred yards of the assault.
This deployment is modified in the attack of a position to include the use of an assembly area. The division deployment order gives a combat mission to the advance guard and march directions to the several columns with a view to executing a preconceived maneuver. While the elements of his command are carrying out these orders, the division commander watches the development of the advance-guard action and, with a minimum of delay, issues a verbal attack order to his principal subordinates.
The coordinated attack from the Japanese point of view does not imply passing into assembly are as. However, this passage into assembly areas, called kaishin , usually is observed in the attack of a position. If a coordinated attack follows the meeting engagement, columns, deploy directly behind the line of departure ( tenkaisen ) without halting prior to arriving on it. No special time is allotted for ammunition issue and final reconnaissance.
(3) Deployment in piecemeal attack.
In the piecemeal attack the troops are committed to action in order of their arrival on the field. The division commander, decent ralizin g control to his column commander, limits himself to a designation of routes of advance with a view to subsequent attack in the desired directions. No division tenkaisen , no common hour of attack, and no detailed plans for coordination between the various arms are stipulated.
Despite regulations specifying the coordinated deployment and attack, the piecemeal method is very common in map problems, on the maneuver ground, and in observed operations. Often this is the result of the precipitate action of the advance-guard commander who gets himself seriously engaged on his own initiative. In such an instance, a sort of hybrid deployment sometimes is executed with a part of the main body going in piecemeal 'to help the advance guard, while the remainder makes an orderly deployment.
Occasionally, a column commander has been known to stage a piecemeal attack all of his own in a situation where the prompt seizure of a terrain feature on his front seemed essential to the subsequent success of the division. Such action was taken without waiting for orders or authorization from the division commander.
Prior to contact, the rate of march of the infantry as it enters the zone of effective hostile artillery fire is reduced. In this zone the Japanese artillery moves forward by bounds in units of battalion strength while furnishing continuous support to the infantry. The theoretical rate of movement forward for this artillery is 2.5 miles per hour, although this may be increased to about 5 miles per hour if a battalion is allotted a road for its exclusive use.
As the range limit is reached the battalion prepares to move forward. When contact becomes imminent, the Japanese transport regiment and the unit trains are halted in a sheltered location. The advance section of the transport regiment will often be as close as 2.5 miles to the anticipated contact, while the trains are normally about 5 to 6 miles in the rear of this line. The remainder of the transport regiment will be behind the trains.
4. MEETING ENGAGEMENT.
a. Doctrine.
The meeting engagement is the foundation of Japanese combat training, with official regulations giving more space to it than to any ather form of combat. Japanese military writings define the meeting engagement as the collision of two hostile forces in motion, or the meeting of a force in motion with one which has halted but has not had time to organize a detailed position. Training strongly emphasizes this form of combat as allowing the optimum development of the alleged Japanese aptitude for swift and decisive offensive action.
b. Characteristics.
Artillery seems to be assigned missions in excess of its capabilities. Aircraft are expected to conduct constant reconnaissance of the situation of enemy and friendly troops as well as to cooperate with the artillery. Tanks may be used independently or in direct support of the infantry; when they are sent on distant raids, other mobile units, if available, may accompany them.
c. Rules.
The rules governing the Japanese in the meeting engagement may be summarized as follows:
(1) The seizure and retention of the initiative.
(2) Bold, independent action by subordinate commanders.
(3) Prompt occupation of important terrain features.
(4) Energetic leadership during combat.
In the words of a Japanese writer "The Imperial Army seeks to wage a short war to a quick and decisive conclusion. The meeting engagement conforms to this spirit and is to be sought whenever possible."
d. Organization of the attack.
In the organization of the infantry for combat, it is indicated that the advance-guard infantry becomes one wing and executes the holding attack. The second regiment executes the main attack, and it may deploy as the other wing along a line of departure, generally in prolongation of the advance-guard position.
About one regiment of infantry is held in division reserve. The attack order is issued when the enemy is fixed in a given area where contact is expected, but often prior to making actual contact and before the advance guard has developed the situation. The order assigns specific objectives to the infantry wings, or a very general attack mission, depending upon the degree of clarity of the situation. Specific objectives would be such as "to attack the hostile forces on X ridge and seize the X position," while a general attack mission might be something like "to advance in the direction of Y and locate and attack the enemy's right flank." This latter type of objective is appropriate in an obscure situation when the plan of maneuver is predicated largely on a study of the terrain.
In any case, the attack direction given is one which is certain to take in flank any formation or position which the enemy may reasonably assume. A study of Japanese attack orders reveals that in an extreme case an order was issued 7.4 miles from the expected point of contact of the advance guards,
e. Employment of the artillery.
(1) General . The artillery order indicates the location of the position in general terms. Detailed reconnaissance is made by artillery commanders to determine the exact locations. Attachment of artillery to infantry is considered to be justified when:
- the front of the attack is very wide;
- liaison with the infantry is difficult;
- combat begins unex pectedly;
- the terrain is broken and wooded.
(2) Missions . Theoretically the division is supposed to retain control of the artillery and coordinate its action, but in practice this is often neglected. Typical missions during the successive phases of the meeting engagement are as follows:
| PHASE | OBJECTIVES IN ORDER OF IMPORTANCE | PURPOSE |
| I. (During the approach march and deployment) |
Hostile artillery and machine guns firing at extreme ranges. | To cover the deployment of infantry. |
| II. (During the attack) |
Hostile infantry, artillery, and reserves. | Close support of infantry. |
| III. (During final assault) | The area of the decisive attack, the enemy reserves. | Neutralization, interdiction, and harassing of movement of reinforcements. |
f. Organization of the piecemeal attack.
In the piecemeal engagement columns are organized into wings and receive attack directions and the attachment of the proper auxiliary arms. There is no coordinated deployment of any unit larger than a battalion.
The artillery, less detachments, is kept under division control. The maneuver takes the form of a frontal collision without any effort to coordinate direction of the various columns to, obtain the effect of envelopment.
5. FORMS OF THE ATTACK.
a. Envelopment.
The Japanese consider the envelopment as the preferred offensive maneuver, Envelopment will be accompanied by a determined frontal pressure, while the main force attacks a flank. In ascending order of effectiveness, the envelopment may be single, double, or a complete encirclement (kanzen hoi).
Contrary to generally accepted tactical principles, the Japanese are willing to try a double envelopment without any considerable numerical superiority and regard it as possible, sometimes, even By an inferior force which relies on surprise and deception. The Japanese commander may seek to obtain envelopment in one of the following ways:
The force advances in two or more parallel columns, with one or more columns directed toward the enemy flank and rear during the advance to contact. This is considered the normal procedure for divisions. The force advances with certain units in the rear which can later be deployed to execute a flank envelopment. This is especially applicable to small units. After the force has encountered the enemy and partially deployed, some units may be moved laterally for envelopment if natural cover, darkness, Fog, or smoke are available.
This is considered feasible only under the most favorable conditions. Those units of a division executing the frontal holding attack often will make a close-in envelopment in performing their mission. Units of this force, such as squads and platoons, seek to Obtain the effect of flanking fire (shageki hoi).
The question of which flank to envelop is decided by weighing normal factors, such as terrain and location of hostile reserves and heavy weapons. To increase the effectiveness of the envelopment, the Japanese often send a small force around to attack the enemy rear. When such a movement (Ukei) is employed, the force sent around by a division in attack is relatively weak, comprising about a battalion reinforced by light artillery and a squad of engineers. The mission of such a turning force is often similar to that of a pursuit detachment; in fact, this force may become a pursuit detachment if the main attack succeeds.
b. Frontal attack.
Japanese regulations contain the usual adrnonilio11s against a frontal attack. Situations which may give rise to a frontal attack are those to which Allied armies are accustomed. In observed practice, however, the time element, or the fear of allowi11g the enemy time to improve his position, often is allowed to justify a questionable decision to make a frontal attack.
The main effort of a frontal attack is made against a "soft spot" in the hostile line, leading in a decisive direction into the enemy rear areas. An effort is made to penetrate deeply and swiftly at the first attempt by keeping the battle fronts of units in the area of the main attack narrow, making dispositions in depth, and coordinating employment of artillery. Tanks, if available, may participate. In general, the Japanese are weak in artillery support and depend heavily on extensive employment of their infantry guns and infiltration practices. The impressions gained from a study of Japanese teachings on the forms of attack and their application in practice show that the Japanese will attack in many cases where the orthodox decision would call for less positive action. The attack may be rash and costly but will never lack vigor and de Lermi11ation. Furthermore, the frontal attack, often with inadequate supporting arms, is not uncommon.
6. ATTACK OF A POSITION.
a. Organization of attack.
When the enemy has had time to occupy and organize a position, the Japanese commander endeavors to fight the decisive action outside of the organized area by turning the position. This often is at tempted by an approach over terrain believed to be impassable or under adverse weather conditions. The intention in both cases is to achieve surprise in the direction and time of attack. The presence of other Japanese units on the flanks often limits the possible maneuver area. Technique of such an attack resembles that of the coordinated meeting engagement in the use of the
Figure 1. Diagram illustrating Japanese attack of position. |
approach march and the development of the situation by the advance elements; it differs in the amount of time necessary
for reconnaissance and attack preparations. However, the need for care fully executed attack preparation s, according
to the Japanese, must not be made the excuse for allowing the enemy undue time to improve his position.
As shown in map problems, when a commander encounter s a position which has been strengthened during a period of several days, he ordinarily drives in the covering forces and reconnoiters during all or part of one clay and launches his main attack the following morning. He appears quit e capable of attempting all of this in one day if time is pressing. b. Frontages and distances. The following frontages are averages derived from studies of several problems:
The following distances are average distances from the line of departure:
|
In the decisive effort the average frontages of attack are:
|
Frontages are from 20 to 25 percent greater for units marking a secondary attack.
The average distances of command posts from the line of departure for the attack of the main positions are:
|
c. Driving in covering forces.
(1) Procedure.
In order lo obtain adequate information about the main defensive position, the Japanese division ordinarily first drives in the hostile covering forces and then executes the necessary reconnaissance for the main attack. If these covering forces are weak and do not form a continuous front, the advance-guard commander drives them in on his own initiative; otherwise, and the division commander organizes the operation under cover of strong artillery support.
In the typical case, this attack takes place in the afternoon of one day, and is followed by attack of the main position at daylight the next day or shortly after. When the opposing forces occupy positions very close together, two nights may be necessary to get the attacking forces and materiel into position.
(2) Continuous attack.
This procedure of successive attacks, while designated as orthodox in Japanese Combat Regulations, often is replaced in practice by a continuous attack on both outpost and main positions. IL is not clear when this variation is considered justified, but apparently the deciding factors are whether the artillery can support the attack through both positions without dis placement, and whether the time element is pressing. When the continuous attack is made, that on the outpost line becomes a phase of the main attack, and the attacking infantry usually pauses briefly on the captured position, and then continues the assault. In about half of the map problems studied the continuous method was adopted, although there was no apparent need for special haste in launching the attack.
d. Conduct of the attack.
(1) Infantry.
The typical disposition of the units in the assault is into wings, with the preponderance of strength in one wing assigned to make the main effort, while the other wing makes the secondary attack. The infantry units, in accordance with the plan of deployment, advance from the assembly areas to their assigned positions along the line of departure, where they make final attack preparations.
When the attack is to jump off about dawn, the advance to the line of departure is made under cover of darkness; if made in daylight, all mea ns are utilized to conceal and protect this movement. In problems, the lines of departure vary from 550 to 2,000 yards from the enemy main position, and the line is chosen so as to be protected from effective small-arms fire. When the attack on the main line of resistance and the outpost line of resistance is continuous, a pause and a realignment may take place along the rear edge of the outpost position which then becomes a phase line in the course of the attack, one of the few uses made of this technique of control. Boundary lines between units are rarely used below regiments.
Attack objectives (terrain features) or attack directions are given the front-line infantry units according to the known details of the enemy position. Normally, the line to be reached by the attack is in the zone of the hostile artillery. The hour of attack is usually about 1 or 2 hours after dawn, as the Japanese have little confidence in the ability of their artillery to make ready during hours of darkness to fire a daylight preparation. In an attack, the order for which is issued in daylight, a minimum of 4, hours is allowed between the time of the attack order and the assault to provide for distribution of the order, for the movement of troops, and for artillery preparation. The division reserve is assembled under cover in the zone of the main effort approximately 1¼ to 2 miles from the line of departure.
(2) Tanks.
When available, tanks are brought up with great secrecy to assault positions. Here they are attached to front-line battalions and jump off at the same time as the front-line infantry, The infantry is warned not to stop if the tanks are destroyed but to continue the advance. Tank missions are the breaching of enemy wire and the destruction or neutralization of hostile elements.
(3) Artillery.
The division artillery frequently is reinforced with light and medium battalions. Its combat organization usually provides for a direct support group of from one to two battalions for each wing without any artillery being held in general support. If a fourth battalion is attached, it may be employed in general support for counterbattery missions.
Fire missions are varied according to the phases of the proposed action, a typical assignment when there is no reinforcing artillery being the following:
| NUMBER | PHASE | MISSION |
| I | Attack of the support position. | Counterbattery by one battalion; direct support fire by two battalions, with special attention to the troops of the main effort. |
| II | From the occupation of the outpost lines of resistance to the opening of the artillery preparation. | Counterbattery, harrasing, and interdiction fires. |
| III | The artillery preparation. Duration one to two hours. |
Subdivisions (approximate). 1/2 hour of fire for adjustment (in daylight). 1/2 hour for wire cutting accompanied by counterbattery. |
| IV | The attack. | Direct support fires with particular attention to the main effort. |
All division artillery deploys for the attack of the outpost line of resistance. The artillery positions are pushed forward to within 500 to 800 yards of the infantry line of departure so as to be able to support the attack of the main position without moving. At the time of the attack on the main position, one or· two artillery batteries often are attached to the main effort as accompanying artillery.
The ammunition allowance for the light artillery in an attack of a position is usually 3 to 3½ days of fire (1 day of fire for 75-mm weapons equals 300 rounds). Gunnery methods seem to be elementary, with main reliance on axial ground observation, with observation posts generally close to the guns. The Japanese Combat Regulations imply, however, that the artillery is capable of registering at night and of opening fire promptly at dawn. Two to three airplane normally are attached to the Artillery for observation and command purposes.
(4) Antiaircraft artillery.
The usual attachment of antiaircraft artillery to division appears to be a battalion consisting of three gun companies (and sometimes a searchlight company) . Such machine guns as are in this battalion are for its own local defense. In the attack of a position, the gun companies are placed in the zone of the main effort, in initial positions about 2,700 to 3,300 yards from the line of departure of the infantry.
(5) Cavalry or reconnaissance.
About one platoon is normally attached to each wing for duty as messengers and orderlies. The remainder is divided for flank protection, with the bulk on the decisive flank. As the strength of the division cavalry regiment is light, the combat value is not as great as might be expected.
(6) Engineers.
Engineer missions in the typical case are:
- Maintenance of communications.
- Assistance to the artillery and tanks.
- Wire cutting.
- The removal of obstacles.
The Japanese normally assume there is some wire in £rout of the hostile position. An attack order therefore includes provisions for cutting the wire by detailed destruction fires by the artillery ; by artillery fire in the most important places, supplemented elsewhere by handcutting by troop. from other arms; by the artillery cutting the wire imperfectly at all points, with the cutting to be completed by hand. Where there are several band s of wire, it is nor mal to make the destruction of the first hand the exclusive duty of the infantry and engineers. Where obstacles other than wire are encountered, the Japanese rely on small teams composed of units from the size of an infantry platoon reinforced by a squad of infantry pioneers down to a reinforced Squad.
The main team is reorganized into:
(a) An infantry squad assault section,
(b) A pioneer assault section,
(c) A support section.
(d) a mopping-up section.
The first two of these are each broken down into an assault demolition group and a reserve group. The equipment with which they are supplied includes Bangalore torpedoes, flame throwers, demolition charges, w-ire cutters, and smoke candles. The commander of the platoon team is to have each of his men tho roughly familiar with the terrain, the enemy situation, and the locations of field works and the obstacles that cover them. In his order for the assault, he must make clear the preparations to be made prior to the assault, the fire mission s to be carried out, the fields officer of enemy weapons, and the location and condition of gaps already made through the various obstacles.
Advance to the assault is made by crawling when the terrain or hostile illumination requires it . The support section provides fire cover. When the defender discovers the attack, a shift is made to the preliminary assault formation, and movement is continued by crawling. The final assault is not launched until the second zone of obstacles has been breached or this operation, the support section is used to neutralize one or more gun ports of the main objective, and to place smoke on other positions the fire of which must be avoided.
The assault units move forward through gaps cut by the artillery and attack the objectives assigned to them. They are followed closely by the mopping-up section which aids in the taking of tl1e pill boxes and in the reorganization of the position. The use of flame throwers in this final operation appears to he confined to the infantry pioneer assault section. To breach a well-organized position several assault teams may be used, and their over-all control is vested in the company or battalion commander, depending on the scale of the operation under taken. The integration of the work of the assault teams into the main infantry attack is not clear, nor are the methods and requirements of large-scale planning well worked out.
(7) Medical troops.
About one-third of the medical troops are assigned to support each wing; the remainder are in reserve. These detachments set up a11d op rate division collecting (dressing) station located behind the regimental dressing .stations. Locations are from 1,600 to 2,200 yards behind the line of departure. Two field hospitals are set up about 2,500 to 4,000 yards from the line of departure; the division is capable of setting up one additional hospital held initially in reserve.
(8) Ammunition supply.
The advance section of the transport regiment (senshin shicho) ordinarily open an infantry ammunition distributing point in rear of each wing ns well as one artillery distributing point.
e. The assault.
Attacking units do not try to retain alignment, and where the going is easy they press ahead. When gassed areas may he encountered, the leading wav e includes decontamination squads. A gassed area is avoided when possible; if it must he traversed, the local gas squads use their light decontaminating equipment to neutralize it.
When such equipment is insufficient or absent, the troops are taught· to cross the gassed area resolutely at an increased gait. The artillery advances by bounds close behind the infantry; its forward observers advance with the infantry. As the attacking infantry approach the enemy positions, small-arms and artillery fire is increased, and reserve units arc brought up. The cavalry closes in on the enemy flank and rear, and finally a bayonet assault is launched. The division reserve is used to extend and exploit an advantage gained, to meet a counterattack, or to extend the flank of the enveloping forces. If darkness interrupts the attack, it will be either continued at night or renewed at dawn.
7. PURSUIT.
a. General.
Japanese field service regulations place the normal emphasis on the need for pursuit to reap the full fruits of victory. They also recognize the existence of many deterring elements, such as fatigue of the troops,disorganization, and depletion of supplies. In spite of these, the Japanese commander is urged to pursue relentlessly to avoid the need for another battle against a reorganized and possibly reinforced enemy.
b. Preparation for pursuit.
The Japanese commader throughout an engagement plans constantly for the pursuit. The enemy is observed carefully, especially at night, for signs of an intention to withdraw. To determine this intention, the Japanese use ground reconnaissance patrols and spies, and they may use observation aviation if it is available.
When these means are inadequate, the commander is urged unhesitatingly to stage a local attack to gain the required information. While he is pushing this reconnaissance, he makes preparations for a possible pursuit. These preparations atke the form of alerting certain units of immediate pursuit, of assembling sufficient ammunition for the operation, and of outlining a tentative administrative plan.
c. Types of pursuit.
While the quick destruction of the defeated enemy is the object of all pursuit, this cannot always be effected immediately by a sing le simple maneuver. In seeking to destroy the enemy, the pursuer usually will try to fix him by direct pressure while enveloping or turning one or both flanks. If this maneuver fails, he may try to push the retiring enemy off his line of retreat or into a disadvantageous position where he can be attacked more effectively.
In recognition of these differing situations, Japanese writers treat the operation under two types: Type 1, where the enemy is destroyed near the field of battle where he sustained his initial defeat; and Type 2, where the enemy has partially succeeded in extricating himself and the pursuer must Lake distant objectives deep in the enemy's rear after resuming semi march dispositions. In both types, the destruction of the enemy is accomplished by fixing him with direct pressure, while mobile pursuit detachments moving around the flanks, occupy the critical points along his line of retreat and fall upon his rear.
d. Technique of pursuit.
(1) Types.
In Japanese tactical theory, the first type of the pursuit finds its best example in the case of the daylight withdrawl of a hard-pressed enemy. The withdrawal is observed by the attacker, who immediately redoubles the frontal pressure, while available reserves are quickly formed into pursuit detachments which turn the enemy's flank and fall upon his rear.
Boundries between front line units are readjusted as needed. The destruction of the enemy thus is accomplished in or near the original field of battle. The detailed action of the separate arms is essentially the same as in the second type, except that distant marches, with a reforming of march columns by the frontal pressure force of the infantry, are not required.
The second type of the pursuit is regarded as the usual one by the Japanese, wherein the enemy succeeds wholly or partially in disengaging himself and begining a withdrawal. The initial withdrwal usually is accomplished under cover of darkness and may not be discovered at once. When the Japanese front line unit commanders find out what is occurring, the theory is that they renew the attack individually and upon their own initiative in an effort to push through or around the hostile covering forces. As these Japanese units penetrate the enemy position, reserve units, formed into pursuit detachments, move around the flanks with objectives deep in the enemy rear.
When the Japanese front line infantry units have passed through the zone of resistance of the covering forces, the division commander halts them, organizes and sends forward additional pursuit detachments, and causes the remainder to form march columns to follow in the trace of the pursuit detachments. As this form of pursuit is considered to be usual, the subsequent remarks on the missions of the various arms apply specifically to this type, although they are also applicable with slight modification to the first type.
(2) Front-line infantry.
All units are individually responsible for discovering the hostile intention to withdraw, After such discovery, they drive into the enemy covering force, on their own initiative. In order to get through the enemy covering forces the Japanese prefer to turn the organized localities by maneuver or by infiltration through the gaps. When neither is possible, a quickly organized attack on a narrow front is indicated. As the action of front-line units is decentralized, most of the division artillery is attached to front line infantry regiments.
Tanks are sent in lo block the enemy's retreat an{! lo attack his artillery and command posts. To avoid a serious loss of control, the division commander usually indicates a line in rear of the probable enemy covering position where the troops halt and reform for further pursuit. A part of the front-line infantry is then organized with previously formed pursuit detachments. The bulk of the division reforms into march columns and follows after the pursuit detachments.
(3) Artillery.
When the enemy is discovered to be withdrawing, the artillery endeavors to disrupt the enemy retreat by interdicting the important defiles and bottlenecks in the road net. As the front-line infantry penetrates i11to the covering position, the artillery, attached to infantry units, follows by hounds close behind the advancing troops and concentrates its fire on the resisting enemy infantry. Some artillery is attached to pursuit detachments..
8. COMMENTS AND CRITICISM.
a Meeting engagement.
(1) Principles.
In the Japanese meeting engagement all elements of the division show boldness and vigor. Speed in decision and execution is stressed in regulations and carried out in application. A commander encountering a Japanese division may expect to receive a quick energetic attack, and, unless his covering forces are solidly deployed on their position, the Japanese attack is likely to upset his own plans for a coordinated attack.
(2) Piecemeal action.
In practice the Japanese have shown an exessive willingness to engage in piecemeal action. In the situation in which the Japanese commander has decided to make a piecemeal attack, it will be found that time is pressing, and there is usually a limited objective, but not necessarily numerical or material superiority. There is a tendency to make wasteful, piecemeal action the rule rather than the exception, and this developes a dangerous overconfidence, unjustified when faced by first class troops.
(3) March formation.
The march formation, in which the division commander is also a column commander, is awkward, for it needlesly burdens the division commander with the details of organizing and commanding a column. It complicates the handling of the advance guards which are usually not coordinated under division control. In fact, the advance guards of columns adjacent to the one commanded by the division commander are generally ignored in the division plan of maneuver. As a result, the division does not appear to develop behind solidly organized covering forces which can assure am umimterrupted deployment through coordinated defensive action, even though the numerical infantry strength of the advance guards is usually large, averaging from a third to half of the infantry of the division.
(4) Attack in the meeting engagement.
The advance guard, reinforced, frequently is used to make a holding attack. Durig this operation, it is usually deployed on a wide front which makes the organization and control of an effective attack difficult. The close-in ebvelopment is the form of attack most frequently chosen because of the ingrained desire to get the attack off quickly and because of the realization of the relative weakness of the organic division artillery. Thi sweakness is enhanced by the siting of the artillery pieces in a central location which limits the frontal distance on which fire can be brought and which, therefore, restricts the width of any possible envelopment.
(5) Summary.
In summary, the characteristics of the Japanese division in the meeting engagement are:
(a) Rapid, aggressive action by all elements.
(b) A tendency of uncoordinated piecemeal action.
(c) Development behind weakly linked covering force.
(d) Frontal attack or restricted close in envelopments.
(e) Inadequate artillery support.
(f) Sacrifice of proper reconnaisance and organization to obtain speed in attack.
(g) Attack through terrain generally considered impassable.
b. Attack of a position.
(1) Characteristics.
In their concept of the attack of a position the Japanese show complete disregard of casualties in pressing it to a successful conclusion. Their campaigns initially met with a great measure of success in tropical countries because they had trained extensively in jumgle terrain and adapted their technique to capitalize on what their enemies consider hindrances and handicaps. The following characteristics were common to their campaigns:
(a) Careful, meticulous staff work in the detailed planning of the operation, training, and equipping of the forces to be used, and in coordinating and carrying out the action.
(b) Great boldness, both in the conception of the operation and in execution of its details.
(c) Disregard for the enemy and his weapons.
(d) Disregard of casualties in attaining an objective.
(e) Use of surprise and deception.
(f) Abstinence from advance to all enemy airfields nearby and attainment of air superiority in the area of the attack.
(g) Great speed in infiltration, envelopment, and pursuit.
(h) Willingness to attack through terrain normally considered impassable and in adverse weather conditions.
(2) Criticisms.
the willingbess with which the Japanese commander will order an attack on an outpost simultaneously with the attack on the main position has already been mentioned; this is done in spite of the prescription in Japanese field service regulations which indicates that effective reconnaissance can be obtained only after the outpost have been driven in. His shortening of thetime allowed for reconnaissance and preparation has in many cases reduced the already slender chances of reaching the final objective.
The deployment of the division is generally along orthodox lines, exceptingf that the assembly areas are invariably within effective enemy light artillery range.
The plan of maneuver offers nothing of special advantage for the direction of the attack, as it usually culminates in a parallel, frontal, or semi-frontal push executed by the two wings of the division, with one wing - the decisive one - somewhat stronger in infantry and artillery. However, since this form of maneuver is accepted, it has the definite weakness of any stereotyped tactical method; The certainty with which it can be countered. Also it fails to provide for the massing of adequate forces at the decisive points.
Japanese use of artillery is subject to much criticism. The fundamental faukt is that there is generally not enough of it. Weakness in artillery may be the result of a lack of appreciation of the need for adequate fire support, or of a feeling that past experience has not demonstrated the need for stronger artillery. The period of daylight fire for adjustment prior to the fire for effect reduces tactical surprise and diminishes the morale effect of the preparation.
This unwillingness to fire the preparation based on data obtained at night would suggest low technical efficiency. This is confirmed by the long time required to effect registration in daylight. The absence of general support artillery and the attachment of direct support artillery to the infantry reduce the flexibility of the artillery fires and limit the ability of the division commander to intervene promptly in the action by the use of his artillery.
From the picture drawn in the tactical problems, one can feel reasonably sure that the Japanese infantry will jump off, even thogh their extensive preparations have neither destroyed hostile wire nor neutralized the enemy artillery and machine guns. The detailed working of the direct support fires is not described in the problem studied; hence, no estimate of their effectiveness can be made other than that implied by the absence of detailed plans for infantry-artillery liason.
In the detailed administrative plan of the attack, the establishments are located considerably closer To the front line than is considered standard. Lack of depth is characteristic of both the tactical and administrative dispositions of the Japanese divisionand has its origin om their lack of appreciation of the effecr of modern fire power, particularly that of hostile artillery. A period of contact with a well equipped enemy may furnish correctives for this tendency.
In general, although the adverse criticisms are numerous, it is not to be assumed that the Japanese will persist indefinetely in these errors. The Japanese gofts for adaptation and improvisation can be counted upo to remedy many of the faults in their doctrine, but these remedies will not always be applied quickly beccause if such reasons as a lack of productive capacity, a shortage of shipping space, or a fanatical faith in the infallibility of Japanese doctrine.
c. Comments on the pursuit.
The Japanese pursuit theory offers little variation from standard practice, but the poor control exercised by them in combat probably would result in considerable confusion in view of the rather complex maneuvers proposed. Japanese regulations urge the utilization of all available transport, but, in the absence of specially attached motor transport, the division has been incapable of giving the required mobility to the pursuit detachments.
The well known marching power of the Japanese in line with the offensive spirit of the Japanese army, and the war in China has shown that the Japanese pursue just as vigorously and unhesitatingly as with regulations prescribe. The North China campaign was particularly rich in examples of rapid pursuit. in the advance down the Pinghan and Tsinpu railways, the Japanese put their pursuit detachments on freight cars and sent them far into Chinese territory, while the main body of the division followed partly by rail and partly by marching. Where rail transportation was not available, the Japanese organized special motorized units ( kaisoku butai ) to give rapidly to their pursuit.