Motorization, the use of machines to move men and equipment, had begun early in the twentieth century and progressively increased thereafter with technological advances. As a means of movement and transportation behind the front line in France, infantry divisions used cars, motorcycles, trucks, and motorized ambulances. Some field artillery regiments also used caterpillar tractors to move heavier artillery pieces. After World War I all divisions were authorized some motorized vehicles, but neither infantry nor cavalry divisions had enough to move all their men and equipment. Field Service Regulations stipulated that infantry divisions would depend upon army corps or army units to provide transportation in the field.[1]
In 1927 the 34th Infantry, an element of the 4th Division, conducted experiments using trucks to move itself, disembark, and fight. Two year later, in 1929, the Army started a program to motorize eight infantry regiments, four in the Hawaiian Division and four in the United States assigned to the 4th and 5th Divisions. To equip each of these small peacetime regiments, the staff authorized 1 passenger and 4 cross-country cars, 15 motorcycles, and 50 trucks, with most vehicles coming from obsolete World War I stocks. In 1931 Congress appropriated money for the first significant purchase of trucks since World War I, enabling the Army to motorize the supply trains of the 1st, 2d, and 3d Divisions. One wagon company in the 2d Division remained however, because of the reluctance to consign the horse and wagon to the past.[2]
By 1934 the Army had developed motorized equipment for field artillery that equaled the cross-country mobility of the horse and had sufficient endurance to conduct high-speed marches. Motorization of the Regular Army's field artillery began when Congress gave the Public Works Administration money to buy vehicles for the Army. Within five years all Regular field artillery regiments assigned to infantry divisions had truck-drawn pieces.[3]
Besides providing mobility on the battlefield, trucks helped the Army save money between World Wars I and II. In 1932 a crisis developed in the National Guard infantry divisions because they lacked a sufficient number of horses to train the field artillery. After extensive evaluation, the Guard determined that trucks were more economical than horses, and the following year it began to motorize the 75-mm. guns. By the end of 1939 all Guard divisions had truck-drawn field artillery, except for one regiment in the 44th Division.[4]
Mechanization involved employing machines on the battlefield as distinct from transporting personnel and equipment. During World War I the British and French had developed tanks to aid the infantry in the assault, and, using borrowed equipment, the AEF had organized tank brigades before the end of the war. In combat, however, tanks fought in small units, usually platoons, in infantry support roles. Their slow speed and lack of electronic communications capability made any other tactical employment impractical. After the war the tank company replaced the motorized machine gun battalion in the American infantry division. Postwar Army doctrine for tanks still prescribed that they support infantry in
- ↑ T/O, Table 1 W, Infantry Division, 1921; T/O, Table 401 W, Cavalry Division, 1921; Field Service Regulations United States Army (1923), p. 66.
- ↑ Rpt of the Sec of War, 1928, p. 82; WD Cir 29, 1929; Erna Risch, Quartermaster Support of the Army: A History of the Corps 1775–1939 (Washington, D.C.: Government Printing Office, 1962), pp. 717–19; WD Cir 14, 1931.
- ↑ Rpt of the Sec of War, 1934, pp. 40–41, and 1935, p. 7; Ltr, TAG to CGs all Corps Areas, Departments, and Exempted Stations, 26 Oct 34, sub: Reorganization of Field Artillery; Army List and Directory, 20 Oct 1939, pp. 9–10, 15.
- ↑ John S. Shetler, "Motors for the Guard," Quartermaster Review 14 (Mar–Apr 1935): 47–49; National Guard Register (1939), pp. 1422–23.
