AGF Study No. 8: Reorganization of Ground Troops for Combat
DEFINITIONS AND EXPLANATIONS
TACTICAL ORGANIZATION IN MARCH 1942
The accepted principles of organization were announced by the War Department in a directive of 31 March 1942.8 To guide the three major commands in the drafting of tables of organization certain rules were laid down, which came to be called the "ground rules," setting ceilings on overhead personnel such as cooks, orderlies, mechanics and chaplain's assistants, and encouraging other economies such as the substitution of trailers for trucks. Everything depended on the definition and enforcement of these rules by the major commands.
Large unit organization, in March 1942, embodied the outcome of the reforming ideas of the 1930's and the establishment of the Armored Force in July 1940. The March directive enumerated six types of divisions: infantry, armored, motorized, cavalry, airborne and mountain.
Infantry divisions were barely emerging from a tumult of reorganization. The main features of the new plan -- triangular structure through elimination of the brigade, adaptation to conditions of open warfare, use of motor transportation only - had been discussed in the Army since the early thirties (had in fact been urged by General Perching in 1920), and tentatively endorsed by the War Department in 1935 and tested in the field in 1937 and 1939. Not until 1940, after the collapse of France, did these ideas crystallize in an approved table of organization. The Regular Army divisions were then physically reorganized. Not until after Pearl Harbor did it prove feasible to bring the National Guard divisions into conformity with the new system. The purely wartime divisions, which began to be activated in March 1942, followed the new pattern from the start.
The infantry division was stated by the War Department on 31 March 1942 to comprise approximately 15,500 men, to be "a general purpose organization intended for open warfare in theaters permitting the use of motor transport," and to have organically assigned to it a minimum of artillery and auxiliary elements, "on the assumption that the division is part of a larger force from which it can obtain prompt combat and logistical support." The division in normal employment presupposed corps troops and army troops. It used motor transport only. It had rid itself of the mixed horse and motor transport which complicated the problem of troop movement and supply, and which still characterized the German infantry division. But it did not have transportation to move all personnel and equipment simultaneously.
The motorized division was an infantry division equipped to move simultaneously by motor. It was designed for use in conjunction with armored divisions. No actual motorized divisions existed until April 1942, at which time the 6th, 7th, 8th and 9th Infantry Divisions were converted to motorized. The 4th and 90th Infantry Divisions were converted to motorized shortly thereafter. Motorized divisions at this time were planned in a ratio of one motorized to two armored divisions. The organic strength was over 16,000, and the provision of auxiliary elements was somewhat more liberal than in the infantry division, "on the assumption that the division may operate independently for limited periods."
The armored division, introduced into the Army in September 1940, was undergoing reorganization under the auspices of the Armored Force in March 1942. In its new form it had a strength of almost 15,000 and included 390 tanks. Six armored divisions had been activated; there were expectations of having almost fifty. The armored division was strong in auxiliary elements, "on the assumption that the division may operate independently for long periods."
Airborne and mountain divisions in March 1942 existed only on paper. The airborne division had no table of organization. It was thought of as a task force to be formed for a particular mission by assigning air transportation to elements of a normal infantry division reinforced by parachute troops. The mountain division, for which a T/O had been developed, was stated to consist of three mountain regiments with appropriate support, using pack transportation and aggregating about 15,000 men. The cavalry division, of which two were active in March 1942, preserved the old square or brigade formation, but was small in size, aggregating 11,000 men. It was decided in May 1942 to maintain the cavalry divisions as horse units, extending mechanization in the cavalry only to the non-divisional regiments and squadrons, and to the cavalry components of infantry and armored divisions.
It was the policy of the War Department to assign organically to the division only such forces as were needed for normal operations. The concept of normal operations varied for the several types of divisions. It was thought that the armored division might normally operate at a considerable distance from the mass of the forces, the motorized division somewhat less so, the infantry division least so. Hence what the armored or motorized division needed in the way of organic elements of maintenance, supply, road repair, etc, was more than what the infantry division needed, since the infantry division could habitually draw support from corps and army. But even the armored division was in principle held to a minimum.
The policy of minimum organic assignment to the division resulted in the accumulation of a large number of non-divisional units. The more the division was streamlined, the more was required of non-divisional support. The strength of non-divisional forces, solely of types required in the combat zone, was greater than the strength of all divisions combined. It came to be 1,541,667 by the end of 1944, compared to 1,174,972 for divisions of all types.
In March 1942 non-divisional units were grouped at three levels - corps troops, army troops and the GHQ reserve. Army and corps each had a normal quota of units. As the division had an organic content set forth in its table of organization, so the army and corps each had an organic content set forth in troop lists describing the "type" army and the "type" corps. As the T/O infantry division consisted organically of three infantry regiments plus division units of other arms and services, so the "type" corps consisted organically of three divisions plus specified corps troops, and the "type" army consisted organically of three corps plus specified army troops. Units not organic in division, corps or army constituted the GHQ reserve. Such units, relatively few in number, were available for attachment as needed to armies, which in turn might attach them to corps or divisions.
The type army and type corps were like the division in having an organic structure. Their purpose, like that of the division, was to combine dissimilar elements into balanced wholes. Unlike the division they were used chiefly for planning, to facilitate the mobilization and training of balanced forces. It was understood that in actual operations armies and corps would consist of such forces as might be assigned or attached in the immediate situation.
In addition to the normal corps there existed the cavalry corps, provided for in the tactical doctrine of the Army but never activated in World War II, and the armored corps, introduced in 1940 and physically represented by the I and II Armored Corps in March 1942. The armored corps was not a type organization for planning; it was thought of as a combat force to control the operations of two or more armored divisions together with such supporting troops as might be provided for specific missions. The idea of an armored army, put forward from time to time by the Armored Force, had never been approved by the War Department.
Changes made by the Army Ground Forces in tactical organization, from March 1942 to the close of the formative period at the end of 1943, will be considered in the following sections in some detail. Since organization by definition implies mutual and simultaneous relationships, it lends itself awkwardly to verbal presentation. However the subject is arranged, parts of it belonging together will be separated by many pages. The essential unity in a mass of complexities may be stated as follows.
The organization developed by the Army Ground Forces represented the impact of General McNair's most firmly held convictions upon principles already basically accepted by the War Department. The aim was to obtain flexibility and economy, which were essentially the same, since flexibility meant freedom to use personnel and equipment where it would produce the most effective results. The trend may be described as
away from the idea of the type force toward the idea of the task force. To say the same thing in other language, it was away from the organic assignment of resources to large commands according to ready-made patterns, toward variable or opportunistic assignment to commands tailor-made for specific missions. The tendency away from organic assignment was evident in the disappearance of the type army and the type corps, in the dissolution of brigades and non-divisional regiments, and in the reshaping of divisions and other T/O units according to organic minima redefined at lower levels. The tendency toward tailor-made commands, i.e., task forces, was evident in the emphasis placed on the idea that armies and corps should consist of whatever troops were necessary for the mission; that the division would normally enter combat reinforced by attachment of non-divisional elements according to circumstances; and that actual fighting would be carried on, not so much by the T/O infantry regiment, for example, as by a combat team made up of the infantry regiment with attached artillery, engineers, etc. The emphasis on attachment, the virtual disappearance of organic troops from the corps and army, and the confinement of organic troops of the division to a strictly defined minimum, made necessary extensive pools of non-divisional units. These non-divisional pools became in effect GHQ reserve troops; they functioned as army troops or corps troops when specifically allotted to an army or corps. Divisions likewise became in effect GHQ reserve, since they were no longer organic in corps but assigned as needed. The whole Army became, so to speak, a GHQ reserve pool from which task forces could be formed -- whether these were called by the name, like the "Task Force A" which sailed for North Africa in October 1942, or whether they were more conventionally called corps or armies.
Last updated 15 March 2006