Infantry, Part I: Regular Army /The Second World War

by John K. Mahon and Romana Danysh

• The Second World War

• The coming of war resulted in the largest expansion of the infantry ever undertaken. During the three years, 1941-43, it increased 600 percent. Although this was 100 percent more than the field artillery, it fell far short of some of the newer arms, for example the antiaircraft artillery, which expanded 1,150 percent and later had to be cut back. In any case, before the conflict ended sixty-seven infantry divisions saw overseas service, plus one mountain and five airborne divisions, as well as a cavalry division which fought as infantry. Even the creation of armored divisions expanded the infantry, since they contained substantial foot components.

• There were in all, at some time during the war, 317 regiments of infantry of various kinds. Among these were types unknown before the war, such as three mountain, twelve glider, and sixteen parachute infantry regiments. In addition there were 99 separate battalions, some of which were also very highly specialized.

• Among the remarkable separate battalions were the 1st-6th Rangers. These were light infantry trained to slash deep into enemy-held territory in order to demoralize the foe in every way they could. Although the ranger battalions were not created by redesignating existing infantry outfits, and so not given any official history before the time of their constitution in 1942, they were nevertheless heirs to a very old and proud tradition. That tradition went further back than the American Revolution; indeed the rules drawn up by Robert Rogers in 1757 for his famous ranger companies that served for England in North America were reprinted for use in training the rangers of World War II.

• The rangers were not the only infantry constituted to perform commando missions. A comparable unit was the 1st Special Service Force, established in July 1942. This force was designed to operate behind enemy lines when snow covered Europe. Accordingly, all its men were volunteers whose civilian aptitudes seemed to prepare them for swift operations in snow. Among them were lumberjacks, game wardens, forest rangers, and professional skiers. The 1st Special Service Force was remarkable also in another way; its personnel were drawn about equally from Canada and from the United States. It was an early experiment in international co-operation, and it worked well. After vigorous campaigning-but not much of it in snow-the unit was disbanded in January 1945 and most of its American personnel transferred to a new regiment, the 474th Infantry.

• Still another commando-type outfit was the 5307th Composite Unit (Provisional), which was organized in October 1943. Its specialization was operation in Burma along the Ledo Road, and its personnel were drawn from men who knew jungle fighting. This unit was commanded by Brig. Gen. Frank D. Merrill and became very famous under the nickname of "Merrill's Marauders." Like the men of the ranger battalions and of the 1st Special Service Force, the Marauders were volunteers. At length, on 10 August 1944 the unit was reorganized and called the 475th Infantry.

• Another type of specialized infantry was that intended to provide the foot elements of the new armored divisions. It was called "armored infantry." The first unit of this type in the United States Army came into being when the old 6th Infantry was reorganized as armored.on 15 July 1940. In addition to the 6th, certain regiments which had been on the inactive list since just after World War I were reactivated to become armored infantry. These were the 36th, 41st, 46th, 48th-52d, 54th-56th, 59th, and 62d Infantry. Most of the armored infantry regiments were broken up during World War II to form separate armored infantry battalions, but the 41st and 36th Armored Infantry-assigned to the 2d and 3d Armored Division, respectively-retained the regimental structure throughout the war.

• Armored infantry differed very little from standard infantry, and Lt. Gen. Lesley J. McNair, Chief of Staff, General Headquarters, objected to its differing at all. The chief variance was that armored troops had enough organic vehicles to move all of their men at once. They shared this characteristic with motorized infantry (an element of motorized divisions), which came into existence in August 1940 and lasted only until July 1943. Unlike motorized, armored infantry had vehicles that could operate cross-country and that were lightly armored to repel small arms fire.

• Several types of light infantry were also extensively tested. One was specialized for jungle action. This type, embodied in the regiments of the 71st Light Division, never had a chance to prove itself in combat. It had not shown to very good advantage in training; hence it was converted to standard infantry in the early summer of 1944. In consequence, it was the ordinary doughboy who, beginning in the fall of 1942, did the jungle fighting in the Southwest Pacific. Another specialized type was organized for use in mountains. It was embodied in the regiments of the 10th Mountain Division, which, unlike the jungle division, enjoyed a brief opportunity to practice its specialty. The 10th Division reached Italy late in 1944 and took part in the fight. Its arrival, however, did not preclude many other infantry outfits from having to fight in the mountains the best way they could.

• The last of the nonstandard types of infantry units to be considered here was the most specialized. It included the foot soldiers who were trained and equipped to reach the combat zone by air and to assault from the air. Their primary mission was to land behind the enemy's main line of resistance and there employ commando tactics. This type, new in the United States, like armored infantry, was first organized in 1940. As with armored, General McNair objected in the beginning to so high a degree of specialization, but by 1942 acknowledged the need for airborne troops.

• Some foot troops that assaulted from the air were dropped behind the enemy's line by parachute. Numbers above 500 were reserved for the designation of paratroops. Thus the lowest numbered paratroop infantry regiment was the 501st Parachute Infantry. In addition, there was a second type of airborne foot troops, called "glider infantry." According to the doctrine, these landed by glider in the airheads cleared by the paratroops to reinforce the latter and to widen the assault upon the rear of the foe. The numerical designations for glider units were drawn from the whole range of numbers below 500. This was the result of an effort to perpetuate earlier history, as in the case of the 88th Glider Infantry, which descended from the 88th Infantry of World War I. Likewise, the 325th-328th Glider Infantry were redesignated from the infantry regiments of the same numbers which had made up the 82d Division in World War I. The same was true of the 401st Glider Infantry of the 101st Division. Both the 82d and the 101st Divisions became airborne on 15 August 1942.

• The World War II infantry also included a few units that were made up of Americans of different racial or ethnic extraction. There was ample precedent-for such outfits. Indian.and Negro infantry regiments were the oldest, but Puerto Rican and Filipino units came close behind. Added to these during the war were several separate battalions, the most conspicuous of which was the 100th Infantry Battalion because it contained soldiers of an enemy race. Its men were American-born Japanese. The 100th Battalion was organized in June 1942, and two years later was absorbed as one of the battalions of a Japanese-American regiment designated the 442d Infantry.

• Another unit of this type was the 99th Infantry Battalion, which was made up of Norwegian-Americans and marked for use in Scandinavia. Although the 99th did not get to the Scandinavian Peninsula until the Germans there had surrendered, it did distinguish itself in the fighting in Europe. Finally, early in 1945, when its use as a separate battalion seemed to be over, it was made one of the battalions of a newly organized regiment designated the 474th. The latter was a remarkable hybrid. It contained many men from the disbanded 1st Special Service Force, some from the 1st, 3d, and 4th Ranger Battalions, as well as the entire 99th Battalion. Another hybrid was the 473d Infantry. Also created early in 1945, it absorbed no groups of nationals but rather the veterans of four antiaircraft battalions coupled with the headquarters of an armored group.

• Early in the war, the organization of scores of new units proceeded along the lines laid down in the reorganization of 1939. The National Guard, however, entered Federal service in square combinations and retained them until directed to triangularize during the first four months of 1942. As in World War I, the reorganization of the National Guard for Federal service wrecked many old outfits and associations. For example, in each of the square divisions one whole regiment of infantry had to be cut away and broken up or associated elsewhere.

• In spite of the wrench it gave the National Guard, triangularization brought with it important benefits. Not the least of these was a very simple tactical doctrine which had the advantage of being applicable to the use of units of any size from squad up to division. This doctrine was developed and well established by the time the National Guard was triangularized. Its essence was that one of the three elements of every level, say one regiment, should, in the assault, fix the enemy in position; a second was to maneuver around him, once fixed, in order to strike a decisive blow; while the third element acted as a reserve. This doctrine gave great flexibility to American infantry.

• During the five years before Pearl Harbor, the position of the doughboy's champion, the Chief of Infantry, weakened. The Chief himself felt that his office was being bypassed in important matters, while the Chief of Staff inclined more and more to the opinion that all of the heads of combat arms fostered schisms within the Army. In any case, during the grand revision of the late thirties, the General Staff, more often than not, overruled the recommendations of the Chief of Infantry. Moreover, the latter had less control over his branch than he thought necessary. For example, in the revamping of the infantry division, his responsibility was held to the preparation of tables of organization and equipment for brigades and below. The end came in the spring of 1942 when the top command was completely reorganized. In that great realigning the Chief of Infantry, together with the other chiefs of combat arms, was eliminated. Thereafter, the problems of the infantry were considered by special branches of the newly created Army Ground Forces.

• General McNair became Commanding General of the new organization. He had been chief of staff of the provisional division that had tested triangularization in 1937, and he believed in the basic principles of the revision that had resulted. Foremost among these was pooling. Its natural corollary was to keep all units lean, because, when extraordinary needs arose, those units could draw from the pools maintained at the next higher level. Another of the important principles embraced by McNair was that which gave the best of men and equipment to the offensive portions of units, and cut the other segments to a minimum. The application of these austere principles was sharpened by the urgent need to conserve shipping space; McNair, therefore, caused infantry organization to be finely combed for excess personnel and equipment.

• A general revision of the tables of organization and equipment (TOE'S) took place in the spring of 1942. For the most part, McNair's principles prevailed, but he was unable to prevent two significant changes in a contrary direction. The first of these was the substitution of headquarters companies for detachments in all battalions. In spite of this alteration the total strength of a battalion dropped by sixteen, the cut occurring in the rifle companies and in heavy weapons. The second change brought a new company, the cannon company, into the regiment. In it were at last to be found the accompanying cannon that officers had been seeking since World War I. As first equipped, the new cannon company contained six self-propelled 75-mm. howitzers and two selfpropelled 105's. It added 123 men to each regiment, but since the other regimental companies were cut at the same time, a regiment was actually enlarged by only 23 men. The TOE's of 1 April 1942 moved automatic rifles for the last, time. These weapons, which were proving themselves more and more valuable, went back to the rifle squad where they had been placed prior to February 1940. They had gone into a separate squad at the insistence of the Chief of Infantry, and they returned to the rifle squad when that office was eliminated.

• The pinch for shipping space continued so great that the War Department requested cuts in the April tables. Accordingly, a Reduction Board was established in November 1942. Before its recommendations were approved, General McNair strove to reduce the infantry regiment by 400 men, a slice which he believed could be made without diminishing the number of front-line riflemen to any great extent. His proposal was made into a new TOE published on 1 March 1943. The chief casualty was the cannon company, which was eliminated altogether; its howitzers were put into headquarters company. This arrangement was shortlived, since the final work of the board resulted in a cut of only 216 which, when finally approved, was embodied in tables dated 15 July 1943. Most of the 216 came from administrative elements and from heavy weapons. The cannon company was back, but this time with towed howitzers. The sharpest reduction in arms that accompanied the drop in personnel fell upon BAR's. These were eliminated from every echelon except the rifle squad, where there was one per squad. This change removed very little automatic rifle fire from the firing line, but it did reduce the number of BAR's in a regiment from 189 to 81 (there being 81 rifle squads in a regiment).

• If a regiment lost any firepower by the cut in automatic rifles, it made it up by the addition of twenty-five .50-caliber machine guns plus one hundred and twelve new 2.36-inch rocket launchers, nicknamed "bazookas." The bazookas, which had splendid attributes for antitank and antipillbox use, were extra weapons; that is, no specific men were designated to operate them. In consequence, each regiment made its own organizational modification to use the new arm. Later the orphan situation of rocket launchers was officially corrected.

• Bazookas and .50-caliber machine guns fitted into General McNair's theory of antitank and antiaircraft defense for infantry regiments. He held that such defense should center on weapons which individual infantrymen, not crews, could operate. Once again, he did not win out 100 percent, for he failed to eliminate either the towed antitank guns from the armament of regiments or the mine platoon from antitank companies: There were, however, changes in the antitank guns: their caliber was increased from 37-mm. to 57-mm., while the number of guns in the regiment dropped from twenty-four to eighteen. Half of the remaining guns were in the regimental antitank company, the other half divided evenly (three each) among the battalions. Considering the mine platoon as strictly defensive, General McNair strove to eliminate it altogether. Accordingly, it did not find a place in the TOE of 26 May 1943; but was back on 15 July, thirty-one strong.

• Removal of tanks from the infantry and the creation of an armored force in 1940 had left unsolved problems in the relationship of foot soldiers to tanks. The principle of pooling took care of the association of tanks with infantry units, for tank elements were simply attached in the quantities needed. This, however, did not help to determine how much infantry ought to be organic to armored divisions. Since these divisions, as first set up, did not include enough foot soldiers, General McNair created pools of separate armored infantry battalions (AIB's) from which the divisions could draw. Later his solution was scrapped, and in the TOE of 15 September 1943 the proportion of organic infantry to armor doubled. In consequence, all but one of the separate AIB's were inactivated.

• Each of the studies of infantry organization, made in the first three years of the war, had to take vehicles into account. The number of motors allowed to units was closely related to the shipping space then available. Shortage of shipping was one of the factors which caused the elimination of motorized infantry in the summer of 1943, since the planners felt that more economical means of moving standard infantry by motor were at hand. The first such means was to attach truck outfits to the infantry for specific movements. This method remained standard until divisions developed the field expedient of piling their doughboys onto their tanks, tank destroyers, and howitzers.

• All these complications were faced by Army Ground Forces during the year from October 1942 to October 1943, and the organization developed for infantry in that year persisted for the duration of the war in Europe with only minor changes. However, when redeployment to the Pacific area became necessary, Ground Forces once more examined the tables of organization and equipment. This time three factors were decisive in the appraisal. The first one was the wealth of combat experience accumulated in Europe; the second, that the scarcity of shipping space had eased; and the third, the death of General McNair. These new factors resulted in a general enlargement of infantry units.

• The new tables were dated 1 June 1945. They carried the implication that the earlier arrangements had been too lean for greatest efficiency. For example, they increased the total strength of an infantry regiment from 3,256 to 3,697, and added weapons and vehicles. Most of the increase took place in rifle companies, which jumped from 193 to 242 men. Indeed, two new sections were added to them, both in the weapons platoons. The first one, called an assault section, was based on the 2.36-inch bazooka (the number of which increased to six per rifle company). With this change, rocket launchers ceased to be orphans. They became the principal weapons of the men in the new section. The other, a special weapons section,. employed a revolutionary type of new arm, the 57-mm. recoilless rifle.

• Further use of the recoilless technique occurred at battalion level. Here a 75-mm. rifle was added to the armament, and a gun platoon was created in the heavy weapons company to operate it. The two new types of recoilless guns, which combined the effect of artillery with the mobility of soldier-carried arms, gave an unheard of weight of fire to the infantry.

• Yet another remarkable change related to the infantry regiment's artillery. All towed guns were at last eliminated from the regiment. The 57's of the regimental antitank company gave place to tanks which mounted 90-mm. guns, while those in battalions went out with the antitank platoons. The cannon company became in effect a tank unit equipped with heavy tanks mounting 105-mm. howitzers. The pieces of the antitank and the cannon companies, mounted as they were on tanks, were much more mobile than their predecessors, and they threw much more metal.

• The organization established in June 1945, slightly modified from time to time, was the one that governed to the end of the conflict. There was, however, one development which went forward apart from the tables of organization. This was an ever widening use of regimental combat teams (RCT's). An RCT was a grouping of combat units around an infantry regiment in order to accomplish a special mission. A typical combat team contained a regiment of infantry, a battalion of 105-mm. artillery, a company of combat engineers, a medical collecting company, and a signal detachment. But, because its very essence was flexibility, any element needed to accomplish the special mission might be attached. RCT's proved of great value in adapting organization to all types of terrain and conditions of combat. They remained, however, temporary arrangements without official history or lineage, and were discontinued when their special mission had been accomplished.

• Before concluding the discussion of infantry organization during World War II, it remains to record a few generalizations relating to the use of infantry in that war. First, it is clear that no earlier conflict had sent American infantrymen into so many different parts of the world. Although specialized units were at first created to fight in extreme zones, mountain, jungle, and arctic foot soldiers carried, in fact, a very small part of the fighting in extreme climates and terrain. As a result, the standard doughboy took over the job.

• The doctrine of fixing the enemy, maneuvering to strike him in flank or rear, all the while holding an element in reserve to exploit an advantage or cover a retreat, applied in all terrains. Naturally the details of using it varied with geography. Thus in Normandy the hedgerows obliged the infantry to work out a team play with tanks and engineers. Likewise, in the jungles of the Southwest Pacific, the coral atolls of the Central Pacific, the desert of North Africa, and the mountains of Italy, it was necessary to develop the exact means by which the doctrine was applied. But in all cases it required closer-than-ever co-operation with the other arms.

• Furthermore, never before had the doughboys been required to use so bewildering a complex of weapons. Perhaps the most confusing of the latter to adjust to was the greatly enlarged class of defensive weapons, which included land mines and boobytraps. These insidious manglers complicated an infantryman's task and introduced a new type of terror into his campaigning. He dared no longer even trust the ground, which had always been his close ally. As a result, it was necessary to learn not only to detect and disarm the enemy's mines and traps, but to lay some effectively for his own protection. Also, he had to learn to use demolition charges and often to improvise them out of materials at hand.

• To add to the confusion, types of grenades (hand and rifle) were multiplied. What is more, their use vastly increased. Whether the enemy lurked in rocks or in dense vegetation, grenades helped to root him out. To supplement them in the business of dislodging the foe from strong positions, new weapons developed. The most notable of these, not already mentioned, was a flame thrower which, carried by foot soldiers or mounted on tanks, did terrible execution.

• Tank and air enthusiasts, observing the Nazi blitzkrieg, had jumped to the conclusion that infantry could be used only to hold ground taken by armor or by air bombardment. This did not prove to be the case. Although foot soldiers, more than ever before, had to learn to co-operate with tanks and with planes, this did not spare them from having to be in the forefront of almost all important assaults. In short, while they could not advance against the enemy without the aid of tanks, artillery, and air, neither could those arms gain ground or destroy the enemy's will to fight without the aid of the infantry. What was required was not a reshuffling of the importance of the several branches, but the development of better techniques by means of which they could work together. Such techniques were far from perfect when the conflict came to an end.

• Battlefield communication continued its trend-which stretched back to the Civil War-toward improvement. For the first time there was radio communication between the elements of a company. By the end of World War II eight radios were included in the rifle company's equipment. Radios and telephones knit companies tighter together, but by no means made them act as one man. Dispersion to avoid the deadly effects of enemy fire threw, squads, or fractions of squads, on their own in combat, particularly in dense foliage, in the mountains, and in night operations. This put a heavier-than-ever burden on the ingenuity of squad and platoon leaders, and even on the individual doughboy.

• Probably the most important technique to come out of the war had to do with landing an attacking force on hostile shores. The doctrine for such operations had been in the process of development by the U.S. Marine Corps since the 1920's. Marine theory worked well, but it required the assistance of special amphibious equipment ,which was not developed until war had commenced. Indeed, in the early landings in 1942, landing forces were obliged to use the vessels that were ready at hand. Gradually, however, landing craft were developed, such as LCI's, LST's, LCT's, amphibious tanks, and DUKW's. In the greatest amphibious operations of World War II, these craft were as essential to success as the weapons of the infantry.

• Whether in landing actions, in airborne assaults, or in advances of a traditional type, infantry was better prepared than in the past to fight on a circular perimeter. This was true because of the many supporting mortars, machine guns, and rocket launchers, made organic to infantry units, which enabled them to throw fire quickly in all directions. Thus, the tendency was to be less sensitive about the flanks than in earlier wars, and to push forward with slighter concern for the progress of the units to the right and to the left.

• During World War II new terrains, new climates, strange weapons, and unfamiliar peoples acted upon American infantrymen. These destroyed thousands of men, put a lifelong mark on others, and changed somewhat the techniques of fighting on foot; nevertheless, in spite of everything, the basic characteristics of the infantry hardly shifted. Foot soldiers continued to be the only carriers of weapons who, in theory, were never exhausted, could always go another mile, and who could be counted upon to move across any terrain in every quarter of the globe.

Notes

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