In September 1940, Congress passed the Selective Training and Service Act (the Burke-Wadsworth Act), the nation's first peacetime draft. The measure provided for the registration of all males between the ages of 21 and 35 and the induction into the armed forces of 800,000 draftees. Securing men was relatively easy, but training them and mobilizing U.S. military production would take time, and much of the new U.S. weaponry was going to Great Britain to keep that nation in the war. Marshall's draftees trained with broomsticks for rifles and logs representing artillery pieces. Trucks bore signs with the word tank.
In World War II, the United States deployed a citizen army, mainly volunteers and draftees. Only two Regular Army divisions in 1940 were sufficiently equipped to be considered real divisions. In any case, most of the army's Regulars were soon scattered to assist in training. At the height of the war, Regulars made up only 3.5 percent of the Army Ground Forces, 2.6 percent of the Army Service Forces, and 1.3 percent of the Army Air Forces. The vast majority of the officers—54 for every 1,000 enlisted men—were National Guardsmen, Reservists, or newly commissioned. Ultimately, 59 percent of army officers were drawn from the ranks.
By 7 December 1941, the army was training 16 Regular Army divisions in the continental United States, along with 18 National Guard divisions, and 2 Army of the United States divisions (composed of Regulars, federalized Guardsmen, and Reservists). There were also the Regular Army's Philippine Division and 12 Philippine army divisions, all of which were destroyed in fighting there early in 1942.
U.S. forces were initially poorly equipped and ineffectively trained, and they lacked supporting weaponry such as tanks and antitank and antiaircraft guns. Ammunition was also scarce. All this changed when the United States fully mobilized for war. By 1944, U.S. steel production was about half the world total. This statistic translated into large numbers of aircraft and ships but also 86,333 tanks, 650,000 Willys jeeps, and 12,573,000 rifles and carbines. The army had so many vehicles that it could have placed every man and woman in the service in them at the same time and had room left over.
Marshall stressed firepower and maneuver. To him, this meant not only that tanks would play a prominent role but also that the entire army would be mechanized and motorized to a degree beyond that of any other military in the world. This emphasis would also enable the army to make effective use of the "triangular" concept, worked out while he was deputy commander of the Infantry School at Fort Benning, Georgia, between 1927 and 1932. The army went from large, foot-bound, 2-brigade (4-regiment) infantry divisions of 22,000 men to highly mobile, 3-regiment, 15,245-man (14,037 in January 1945) divisions. This triangular concept extended to the lowest level. One maneuver unit would fix an enemy formation in place while another turned its flank and the third maneuver unit remained in reserve.
In July 1941, President Roosevelt called for an estimate of the forces required to defeat "potential enemies." Tasked with this assignment, Major Albert C. Wedemeyer estimated that by the end of 1943, Germany and its allies might field 400 divisions. Conventional wisdom held that attacking forces needed a 2-to-1 ratio to overcome defenders, and Wedemeyer thus set the requirement at 800 divisions. Leaving out the Soviet Union, which he believed might not be able to withstand the German onslaught, he calculated that other allies could provide 100 divisions, which meant the United States would have to raise 700. Counting support troops, this would mean a total U.S. military of 28 million men. But the U.S. population was only 135 million people, and industrial production requirements, which experts believed would limit any military to a maximum of 10 percent of the overall population, meant that the armed forces could comprise no more than 13.5 million men. Of this total, the army would get 8.8 million—2.05 million in the air forces and 6.75 in the ground forces. The latter were to be formed into 5 armies, 3 purely offensive task forces and 2 defensive ones. Wedemeyer postulated 215 maneuver divisions—61 armored, 61 mechanized, 54 infantry, 4 cavalry, 10 mountain, and 7 airborne. He thought that with overwhelming air superiority, firepower, and heavy armored components as well as a high degree of mechanization and motorization, such a force would be sufficient. Transporting a force of this size to Europe would require 1,000 ships, and building these alone would take two years, as would raising, equipping, and training the troops.
As it evolved, the U.S. Army fell far short of Wedemeyer's figure. Instead, the so-called 90-division gamble was instituted. Actually, the U.S. Army of World War II numbered only 89 divisions—66 infantry, 1 (dismounted) cavalry, 16 armored, 5 airborne, and 1 mountain. Only 2 divisions did not enter sustained combat, and only 1 failed in combat.
In early 1943, Marshall reorganized the army into three major components: the Army Ground Forces, the Army Service Forces, and the Army Air Forces. In personnel, the army grew to 8,157,386 men and women by April 1945, of whom 1,831,091 served in the 16 Army Air Forces. Many of the army's best soldiers were not in the infantry, however. The Army Air Forces and specialist branches, such as rangers and paratroops, and the service staffs were permitted to skim off too high a proportion of the best-educated and fittest recruits. The infantry rifle companies were, however, called on to fight the Wehrmacht, the most skilled army of modern times.
The army worked on developing new high-firepower weapons. These included remodeled Browning automatic rifles; the Browning air-cooled, lightweight .30 caliber machine gun; the Mark II .50 caliber machine gun (which remains in use); and the superb M1 Garand infantry rifle with an 8-round clip. The M1, designed by John C. Garand and adopted by the army in 1936, fired 40 rounds a minute in the hands of the average rifleman, but an expert could get off 100 rounds in the same time frame. It had 40 percent less recoil than the Springfield '03 it replaced and had only 72 parts, compared to 92 for the Springfield. The Garand could be entirely broken down using only one tool, a .30 caliber round. There was also the lightweight (5 lb) M1 Carbine, which was issued to officers instead of a handgun. Later, the army introduced the M3 submachine gun, most of the parts of which were stamped out. This weapon was capable of a rate of fire of 450 rounds per minute.
The artillery developed new techniques to minimize the time necessary for all guns in a battery to fire on a target and to coordinate the fire of several batteries so that their shells rained down on one spot simultaneously (the "time on target," or TOT, technique). The 105 mm howitzer and the 155 mm "Long Tom" artillery pieces provided the U.S. Army with remarkably effective firepower. Self-propelled guns also enabled the artillery to keep up with the fast-moving armored and mechanized formations.
The army was not so efficient in other areas. Congress had abolished the Tank Corps in 1920 and relegated tanks to the infantry. Not until 1931 did the cavalry, which still employed horses, receive light "tankettes," known as "combat cars." The U.S. Armored Force came into being only in July 1940 after the defeat of France, but its M-3 Grant, designed hurriedly in 1940, was obsolescent before it was built. Even the M-4 Sherman medium tank, the main U.S. and British tank of the war, had trouble matching up with some of the more powerful German tanks. The army had no heavy tank in the field until the M-26 Pershing arrived in Europe in January 1945 because its armor commanders, notably Lieutenant General George S. Patton, believed that tanks should not fight other tanks. Between 1944 and 1945, the 3rd Armored Division alone had 648 Shermans completely destroyed in combat and another 700 knocked out of action, repaired, and put back into operation—a loss rate of 580 percent. The U.S. lost 6,000 tanks in Europe in World War II, whereas the German army never had more than 1,500 tanks operable at any one time.
Despite shortcomings, the U.S. Army had greater firepower than any other army in the world. It was not only the quality and quantity of military equipment and supplies produced but also the speed with which new weapons came on-line. The bazooka antitank weapon, for example, went from development to production of 5,000 units in only 30 days.
The U.S. way of waging war is to use machines if possible to do the killing and to minimize American loss of life. The army carried a strong indirect fire punch, including massive air forces and substantial quantities of field artillery. For Operation cobra, the Normandy breakout in July 1944, VII Corps disposed of 43 battalions of field artillery. In December 1944 in Europe alone, the army fired more than 3 million rounds of 105 mm ammunition. Artillerymen were able to shift and mass fire on a target on a scale never before seen. The time-on-target technique was a devastating weapon. Air-ground coordination vastly exceeded that of other combatants. Joint and combined operations typified the army's campaigns.
Europe was the U.S. Army's principal theater. It was accorded a priority over the Pacific, which affected all fighting and supply efforts. Seventy-seven percent of army divisions, a total of 68, went to Europe, and there were over 3 million army personnel in Europe and the Mediterranean by April 1945. The Pacific absorbed only 23 percent of all army divisions (21). But despite the priority of Europe, the Pacific Theater claimed half or more of the army forces for the first two years of the war. Only in October 1943 were there more divisions in Europe than in the Pacific; 1.8 million army personnel served in the Pacific by the end of the war.
Although green U.S. Army divisions experienced some problems at first, notably in the Battle of Kasserine Pass in February 1943, they also showed a great ability to learn from their mistakes and adapt. As the army gained experience in the late summer of 1944, its units were arguably better, man for man, than the highly touted Germans. Average U.S. infantry divisions could defeat average German divisions and could even match elite German divisions. They were significantly better than Japanese divisions, whose tactics had deteriorated to digging in and dying in place.
Army doctrine and tactics were also basically sound and flexible. The Germans and Japanese were impressed at how quickly the Americans adapted and how rapidly they replaced unsuccessful tactics with effective ones. Communications, engineering, and medical services were the best in the world. Only at the senior command level in Europe did the army show some debatable weaknesses, with a desire to execute the safe rather than the risky course of action—for instance, the broad-front strategy. Yet even that "cautious" approach presented the Germans with crisis piled on crisis, unsustainable attrition, and too much pressure everywhere to allow recovery.
European combat, especially long, multiple-month campaigns, cut heavily into available army manpower. In Europe, 81 percent of all casualties occurred in the divisions, and they were heavily concentrated in the infantry. Units might lose 30 percent of their men in a week, yet they stayed in the line and continued to fight. The 9th Division, for instance, sustained 17,974 casualties in a four-month period, yet it fought on.
The army did not replace combat losses efficiently or in the necessary quantities, despite training 1.1 million men as replacements and despite a peak strength of 99,288 Women's Army Corps personnel to replace men for battle. There were too few divisions to allow frequent rotation off the line for rest and training. Units were usually short of personnel, and replacements from the States could hardly replace battle casualties, let alone nonbattle losses. A flow of replacements from the States was mandatory. But that system did not always work well. Regardless, the personnel system did keep the divisions fighting for extended periods of time. Units learned how to receive, train, and integrate replacements.
The manpower situation was different in the Pacific. Campaigns were usually relatively short in duration and limited in space, with obvious exceptions such as those on New Guinea and Luzon. Battalions and regiments were the key maneuver units, not divisions and corps as in Europe. And in the Pacific, infantry losses were far higher than expected. During the entirety of the war, the U.S. Army sustained in action 937,259 total casualties—killed, wounded, taken prisoner, and missing (234,874 dead).
The U.S. Army had come a long way since 1939. By 1945, it was the best-armed, most-mobile, best-equipped, best-supplied, most-educated, and highest-paid army in history.
John W. Whitman and Spencer C. Tucker
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