The Development of American Armor 1917-1940

Walter Millis in his book, Arms and Men, declares, “The one great, determining factor which shaped the course of the Second World War was not, as is so often said and generally believed, independent air power. It was the mechanization of the ground battlefield with automotive transport, with the ‘tactical’ airplane and above all with the tank.” Panzer divisions spearheaded the German attacks into Poland, France, and Russia. The Germans, Italians, and British employed tanks widely in the North African campaigns of 1940, 1941, and 1942. Armor played an important role in the Russian counteroffensive, which began after the German defeats at Stalingrad, Moscow, and Leningrad. And American armored divisions led the way to the Rhine and the Elbe following the Normandy landing. But American armor did not just emerge in 1944. The United States Army had been developing tanks and doctrine for mechanized warfare since World War I. Throughout the period examined in this article, American armor developed in three interrelated areas: equipment, organization, and doctrine. Slow-moving tanks could not perform the mobile missions envisaged by the mechanized cavalry leaders in the late thirties. On the other hand, slow tanks were acceptable for supporting infantry assaults. Tanks organized into companies for supporting infantry battalions were not capable of accomplishing the same missions as a mechanized force composed of tanks and supported by other arms. Obviously then, armor doctrine depended on, and was a result of, the type of tanks available and the organization of the tank units. To determine how and why American armor developed in the manner it did, it is necessary to focus on each of three elements: equipment, organization, and doctrine. by Timothy K. Nenninger (Reprinted from the January-February 1969 edition of ARMOR )

Chapter I: The World War I Experience When the United States entered World War I in April 1917, tanks had yet to prove their capabilities. Following the Battle of the Somme in 1916, the allies had employed tanks with disappointing results. Because of their poor performance, the American military mission in Paris declared tanks a failure. In view of this, the general organization project for the American Army in France ignored organizing a tank service. But on arriving in France in June 1917, General John J. Pershing detailed a number of committees to study the tactics and organization of the French and British armies. Reporting to the infantry operations section of Colonel C. B. Baker’s commission, Lieutenant Colonel Hugh A. Parker discussed the employment of large numbers of light and medium tanks in conjunction with tactical air power and motorized infantry. Unfortunately, World War I tanks proved incapable of fulfilling the mobile role envisaged by Parker. Another board, appointed by Pershing, which considered the use of tanks, consisted of Colonel Fox Conner, Colonel Frank Parker, and Lieutenant Colonel Clarence C. Williams. The salient point of their report contrasted sharply with the military mission’s report. It concluded, “The tank is considered a factor which is destined to become an important element in this war.” This board considered the French Renault and the British Mark VI satisfactory models for use by American troops. Finally, they recommended the organization of a separate tank service under the command of a single chief who reported directly to General Pershing. During the war, American tank development generally followed their recommendations. Despite these preliminary studies, much preparation remained before an American tank unit would enter combat. Procurement of tanks proved to be the most difficult task. Based on the early studies, and approved by Pershing on 23 September 1917, the project for the overseas tank corps outlined the organization of five heavy tank battalions of 375 British Mark VIs and twenty light tank battalions composed of 1,500 Renaults. As we shall see, this program proved too ambitious and the stress and strain of war prevented its completion. In late November, AEF [American Expeditionary Forces] General Headquarters (GHQ) deemed additional information necessary before the formation of a tank corps. Therefore, Pershing ordered Majors Alden and Drain of the ordnance department, Captain George S. Patton, the commander designate of the light tank service, and Lieutenant Elgin Braine, Patton’s assistant, to study the design, construction, and use of tanks. After observing French tank training and production, these officers submitted their reports to GHQ in early December. Based on the reports and on Pershing’s recommendations, the chief of staff ordered the organization of the American Tank Corps in December 1917. A quartermaster officer with more than 20 years of service in the cavalry, Samuel D. Rockenbach, whom Pershing described as having “special qualifications,” became brigadier general and chief of the Tank Corps in France. As chief of the corps, Rockenbach was responsible for training, organizing, and equipping AEF tank units. A number of problems relative to desirable tank types, organization, and tactics confronted Rockenbach when he reported to GHQ on 23 December 1917. Procurement of tanks was particularly important and proved most difficult. Throughout 1917 and early 1918, American officials in France expected that the AEF would be largely equipped with tanks produced in the United States. On 22 January 1918, the Americans and British agreed to produce jointly 1,500 Mark VIII heavy tanks. Component parts were to be manufactured in the United States and in England. The tanks themselves would be assembled at a factory in France. But the German 1918 offensive and the competition of the American aviation program for Liberty engines disrupted the successful completion of this agreement; both drained resources destined for tank production. Because the Anglo-American agreement provided only for heavy tanks, light tanks had to be built in the United States. In February, the War Department cabled GHQ that 100 American-built Renault light tanks would arrive in France by April; 300 would be delivered in May and 600 per month thereafter. During the spring of 1918, the War Department remained optimistic about shipments of American-built tanks to France. But lack of coordination and difficulties in procuring parts plagued production. By June 1918, it became apparent that no useful number of tanks would arrive from American factories until 1919 — too late for the expected allied offensive. But the American Tank Corps did get its tanks. The French agreed to equip fully two American battalions with Renaults. Under the proviso that it be attached to the British Expeditionary Force, Great Britain equipped one battalion with heavy tanks. The training of tank personnel presented nearly as many problems as procurement. Training procedures for the American Tank Corps followed British policy. Commanders of the tank brigades had responsibility for training all officers, noncommissioned officers, and enlisted men in their commands. Instructors, trained at French and British schools, would assist the commanders with unit training. To ensure uniformity of doctrine, the unit commanders would lead in combat the troops they trained. GHQ established schools on a permanent basis for training instructors and reinforcements. For training unit personnel, each brigade set up temporary courses of instruction. An officer whose name became synonymous with tanks during World War II deserves much credit for training and organizing the AEF Tank Corps. On 3 October 1917, George S. Patton requested transfer to the tank service. Within 3 weeks, Pershing’s chief of staff, James G. Harbord, detailed Patton to duty with tanks, directed him to organize the light tank service, and ordered him to establish alight tank school. Following detached Despite a military mission’s declaration that tanks were a failure, GEN John J. Pershing, Commander in Chief, American Expeditionary Force, appointed aboard to consider further their employment. 11 duty with the French, Patton proceeded to the AEF schools at Langres in December 1917, and began preparations for a suitable school, training area, and tank park. On 9 January 1918, 22 second lieutenants transferred from the Coast Artillery to the Tank Corps. They formed the foundation of the American tank service in France; they were the cadre. Under Patton’s direction, this group of officers immediately began training with the French. Instruction concentrated on basic military subjects: weapons, camouflage, and map reading. Mechanical instruction followed shortly. In early February, Patton went to Saint Aignan to recruit enlisted men for two tank companies and a headquarters unit. He looked for men with special qualifications such as chauffeurs, mechanics, and caterpillar tractor drivers. With the arrival of the first troops at Langres on 17 February, training began in earnest. Because of the isolated environment in which tankers operated, their training stressed the necessity for hard discipline, devotion to duty, and esprit de corps. General Rockenbach had secured 10 Renaults from the French for training purposes. The tanks arrived at Langres on 23 March

1918. Patton, the only American at the schools who had even seen a tank, taught 10 men with marked ability as instructors to drive the tanks. These 10 then instructed small details from each of the companies. Unit exercises began as soon as the troops learned to drive the machines. In these exercises, Patton stressed reconnaissance, gunnery, repair work, and tank-infantry cooperation. As more personnel became available, the tank units at Langres expanded. By 15 August, 900 men and 50 officers had been trained. They formed the 344th and 345th Light Tank Battalions of the 304th Brigade (Tank Corps). While the light tank units trained in France, the 301st Heavy Tank Center was organized at Bovington Camp, England. In February, this unit, commanded by Lieutenant Colonel Conrad S. Babcock, consisted of 58 unassigned engineer Reserve officers and 38 enlisted men. Early in March, three companies of the 65th Engineers, trained at Camp Colt, Pennsylvania, arrived to fill out the 301st Light Tank Battalion. Training of this heavy battalion progressed along lines followed by the units in France. The original officers instructed the newly arrived engineers using borrowed British heavy tanks. On 23 August 1918, the 301st These National Archives photos of 1918 portray the infant World War I light tank element as it trains for combat. Directed to organize the light tank service and establish alight tank school, LTC George S. Patton began with 10 Renaults and 10 men with marked ability as instructors. Above left, LTC Patton, with MAJ Sereno Brett, inspects his tankers. MAJ Brett later took command of the 304th Brigade (Tank Corps) when Patton was wounded. Above right, pioneer tankers perform maintenance. Below, ready for the CMMI [capability maturity model integration] of yesteryear. 12 departed for the front in France under the command of Major Roger B. Harrison. During the war, the tactical doctrine for employment of tanks changed very little. From the time of Ernest D. Swinton’s pronouncements on the use of tanks in 1915 until the Armistice, tanks remained infantry close support weapons. Several factors contributed to this continuity. Mechanically, tanks remained primitive. They were slow; they were mechanically unreliable; they were easily put out of action. If tanks had difficulty accomplishing their primary mission of infantry support, it was difficult to envisage them fulfilling a more independent role as they did in later years. However, tanks carried out a valuable function in the system of trench warfare. Infantry needed a close support weapon to neutralize hostile machine guns and break through the barbed wire. Perhaps the most important reason that tank doctrine changed very little was because it evolved in a static warfare situation. American tanks in battle, while not a failure, were something less than spectacular. Only three battalions, the 301st Heavy Tank Battalion and the 344th and 345th Light Tank Battalions, saw action. Mechanical breakdowns, heavy casualties, insufficient numbers of machines, poor liaison with the infantry, and use over difficult terrain hindered the performance of the American Tank Corps in France. On 5 September 1918, Lieutenant Colonel Patton received orders attaching the 304th Brigade to IV Army Corps for operations against the Saint Mihiel Salient. Assigned to the 1st and 42d Divisions, the tanks’ mission was to assist the infantry in attacking the southern edge of the salient. Because of the difficult terrain, the operations order called for the 345th to follow the 42d Division until it passed the Tranchee d’ Houblons. From this point, the tanks would lead the foot troops in an attack on the towns of Essey and Pannes. Despite heavy shell fire and deep mud, the battalion carried out the plan. The tanks of the 345th overcame several machine gun positions, destroyed a battalion of German artillery, and captured 30 enemy soldiers. Operating with the 1st Division, the 344th Battalion succeeded in cutting the barbed wire and engaging a number of machine guns in the vicinity of the Bois de Rate. A gasoline shortage hampered tank operations on 13 September, the second day of the battle; the tanks had consumed more fuel than anticipated because of muddy ground. The tankers spent 14 September attempting to reestablish contact with the infantry. On that day, an eight-tank patrol from the 344th attacked, without infantry support, and dispersed a battalion of German infantry near Woel. This was the final tank action in the Saint Mihiel operation. Although a lack of serious resistance at Saint Mihiel did not provide an opportunity to demonstrate the full offensive value of tanks, the tankers did provide valuable aid to the infantry. Furthermore, the Americans gained much worthwhile experience in the use of tanks over difficult terrain. During the 4-day battle, the 304th Brigade lost two tanks destroyed by shell fire, 22 ditched, and 14 due to mechanical difficulties. The brigade suffered 14 casualties among its personnel, but only two of these occurred among troops inside a tank. The Meuse-Argonne offensive, beginning on 26 September, was the largest American operation of the war. In the initial phase, the two American light tank battalions operated with I Army Corps. Originally, the 344th was to support the corps’ advance on the front extending from Vanquois to La Harazee. Upon reaching the First Army objective, the 345th would “leap frog” the 344th and continue to support the attack as far as possible. Serious resistance, especially along the edge of the Argonne Forest, necessitated the use of both battalions by the end of the first day of the offensive. Heavy machine gun fire provided most of the resistance, particularly near Varennes. Although the tanks reached Varennes at 0930 hours on 26 September, the infantry did not arrive until 1330 hours. While getting tanks forward and rallying disorganized troops, the brigade commander, Colonel Patton, was wounded. Major Sereno Brett replaced Patton and led the brigade for the remainder of the campaign. On 27 and 28 September, the American tanks answered requests for assistance from the infantry. Although coordination was poor, small groups of tanks assisted infantry squads and platoons to reduce enemy strong points. On the 28th, tanks entered and captured Apremont five times before the infantry advanced, consolidated, and exploited this success. From 29 September until 4 October, 89 American tanks supported the attack of the 1st and the 28th Divisions. During this period, the tankers and infantrymen overcame liaison difficulties and worked well together. In this fighting, the brigade suffered heavy losses in men and equipment because of accurate German artillery fire. Only 30 tanks, many of which were unfit for effective combat because of mechanical trouble, remained in action on the morning of 5 October. The next day, all American tanks withdrew to Varennes for overhaul. It was apparent that there were insufficient tanks to reequip the entire brigade. Therefore, brigade headquarters formed a provisional company, commanded by Captain Courtney Barnard, and ordered the remainder of the 304th back to the Tank Center at Langres. From 16 October until 1 November, the provisional company remained in corps reserve at Exermont. In their last action of the war, several American tanks of the company participated in the general advance on 1 November in the vicinity of Landres-et-Saint Georges and earned the commendation of the commanding general of the 2d Division. Dummy tank used for machine gun training. Rockers simulated tank movement. 13

Somewhat like the 344th and 345th, the 301st Heavy Tank Battalion met with only limited success. Attached to the 2d Tank Brigade of the British Expeditionary Force and equipped with 47 British heavy tanks, the 301st assisted the American II Corps and an Australian corps in an attack on the Hindenburg Line during late September 1918. Of the 34 tanks supporting the 27th Division, only ten actually became engaged in combat. Most of those disabled ran afoul of an old British minefield. Once again, coordination between tanks and infantry was poor. The 2d Brigade operation report concluded, “Due to the fact that the 27th Division had never had an actual operation with tanks, the infantry commanders did not seem to grasp the idea of tanks cooperating with infantry.” In conjunction with the British IX and XIII and the American II Corps, the 301st successfully attacked German positions north of Brancourt on 8 October. The tanks fought through to the final objective, giving effective support to the foot troops. Poor visibility disrupted a II Corps-301st Tank Battalion attack 9 days later; only half of the 20 tanks that started the operation finished. The final attack of the 301st occurred on 23 October when nine tanks assisted two British divisions near Bazuel. The tank commanders reported little opposition and good targets, despite visibility problems and difficult terrain. All nine tanks beginning the assault rallied at its conclusion. The infantry commanders praised the work of the tanks. Following this operation, the 301st remained in GHQ reserve until the end of hostilities. Military experts disagreed as to the value of tanks during the war. Skeptics could point to the experience of the three American tank battalions and ask enthusiasts if this was an example of the ultimate weapon. Poor liaison, mechanical breakdowns, heavy tank casualties (123 percent from all causes during the Meuse-Argonne), and their inability to operate in certain situations contributed to the pessimistic view of the value of tanks. On the other hand, tank enthusiasts found cause for optimism in the success of mass tank attacks such as the British assault at Amiens on 8 August 1918. Luddendorf called this the “black day” of the German army. Sir Douglas Haig, who, in 1917, called tanks “a minor factor under present conditions,” said in his final report on the war, “Since the opening of our offensive in August, tanks have been employed in every battle and the importance of them can scarcely be exaggerated.” The debate over the value of tanks continued for nearly 2 decades after the Armistice. During the early postwar years, the experience of tanks from 1915 until 1918 weighed heavily on both sides of the argument. Rapid demobilization followed the Armistice. As soon as possible, the War Department returned troops to the United States where they were discharged. On 11 November 1918, the Tank Corps consisted of 483 officers and 7,700 enlisted men within the continental United States, and 752 officers and 11,277 enlisted men overseas. By May 1919, most of these troops had been discharged. During late 1918 and early 1919, tank troops from Camp Colt and Tobyhanna in Pennsylvania, and from Fort Benning, Georgia, and Camp Polk, North Carolina, transferred to Camp Meade, Maryland, the Tank Corps demobilization and storage center. Beginning in March 1919, tank troops from overseas began to arrive with their equipment. The French and British wanted to produce new tanks and therefore did not want the models they had loaned to the Americans during the war. At Camp Meade, the Army collected 218 French Renaults, 450 American-built Renaults, 28 British Mark Vs, and 100 Mark VIIIs built at Rock Island Arsenal. The collective worth of these machines was 32 million dollars. These demobilization activities represented the concluding acts of the past war. What about the future of the Tank Corps? In August 1919, Secretary of War Newton D. Baker ordered General Rockenbach to return to Camp Meade as commandant of the Tank Corps. Subsequently, on December 31, Congress fixed the corps’ strength at 154 officers and 2,508 men. Rockenbach protested that this allotment was insufficient to operate in time of war. He maintained that the United States needed at least two tank brigades. But Congress was in no mood to appropriate funds for a large military establishment. Tankers had to be satisfied with a small organization and confine their efforts to improving their service with the means at hand. Congress charged the Tank Corps with formulating sound tactical doctrine, developing improved tanks, and disseminating information on the value of tanks. No one needed to prod tankers into lobbying for their service. Tank Corps officers, particularly George Patton, Sereno Brett, and General Rockenbach, began to impress upon military and civilian officials the need for tanks in modern warfare. As commandant, Rockenbach was in a particularly advantageous position to express his views. In testimony before Congressional committees, in articles for military journals, and in speeches for military gatherings, Rockenbach defended the tank’s performance during the war and stressed the need for developing improved tanks in the future. During a lecture at the General Staff College, Rockenbach said the Tank Corps had resisted entangling alliances with any of the traditional branches, but its support in combat would be of value to all of them. According to Rockenbach, the use of tanks reduced infantry casualties. He thought that function and design should govern Tank Corps needs in the future. To carry out their mission, tanks should be designed to cross any defensive position, go anywhere the infantry could, and possess sufficient armament to cope with protected hostile machine guns. Despite the necessity of close association between tanks and infantry, Rockenbach opposed permanent attachment of tank units to infantry divisions. He maintained that tanks could not be used in every situation and should not be wasted on a division operating in unfavorable terrain. Before a Senate subcommittee, Rockenbach defended the wartime tank organization. He said that the Tank Corps should remain a separate entity assigned to GHQ for use as the tactical situation dictated. Because of their special nature, tanks needed their own organization to coordinate the procurement of proper equipment with the Ordnance Department, conduct the necessary specialist training, and plan tank-infantry operations with GHQ. In response to a lecture by General Rockenbach, Major General Charles P. Summerall, an outstanding wartime corps commander, wrote, “Far from disagreeing with any part of the lecture, the only comment I heard... was that you had presented the subject in a very conservative manner and that all were in hearty Chapter II: The Tank Corps Reorganized (Reprinted from the March-April 1969 issue of ARMOR ) 14 sympathy with the development and use of the Tank Corps.” Some of the Tank Corps’ own officers agreed with Summerall that Rockenbach was too conservative. Rather than experimenting with and developing new tanks, Rockenbach sought to maintain the status quo. Patton’s biographer wrote that upon return to the United States after the Armistice, Patton vigorously promoted research, development, and training: three activities essential to the improvement of tanks. Soon after arriving at Camp Meade, Patton realized that several forces, including General Rockenbach, combined to thwart his efforts. A close friend of Patton’s during this period, then Lieutenant Colonel Dwight D. Eisenhower, expresses similar sentiments in his book, At Ease! During the war, Eisenhower commanded the tank training center at Camp Colt. After the end of the war, he went with the tank units to Camp Meade. On the controversy surrounding tanks, Eisenhower writes that he, Patton, and several other young officers disagreed with accepted doctrine. They thought tanks should be fast and should attack in mass formations. This group of officers conducted experiments with World War I tanks and held demonstrations for War Department officials. Several of the group, including both Patton and Eisenhower, wrote articles for military journals expressing their “revolutionary” ideas. But the War Department disapproved of their divergence from established doctrine. Eisenhower writes, “I was told that my ideas were not only wrong, but were dangerous, and that henceforth I was not to publish anything incompatible with solid infantry doctrine.” Confronted with such pressures, both Patton and Eisenhower soon left the tank service. Official War Department doctrine called for tanks to be used as close support weapons for the infantry, thus the wartime practices for the employment of tanks would continue. Aboard of officers, convened by the War Department in 1919 to study tank tactics, recognized the value of tanks as an adjunct to the infantry but declared them incapable of independent action. To emphasize further the association of tanks and infantry, the board maintained that the “Tank service should be under the general supervision of the chief of infantry and should not constitute an independent service.” Their recommendation that tanks be under infantry control broke with the wartime arrangement by which the Tank Corps retained autonomy from branch authority. Peacetime exigencies gradually pushed the War Department into placing tanks under the control of the chief of infantry. Ultimately, the question of a separate Tank Corps came before Congressional committees holding hearings on the reorganization of the Army. The question raised in these committees was not over the value of tanks, but over the necessity for a separate service. General Peyton C. March, the chief of staff, said that American military authorities were fully convinced of the offensive value of tanks. March himself believed the Tank Corps was “technical enough and important enough to keep as a separate arm.” Disagreeing with March, General Pershing expressed the belief that tanks should be under the control of the chief of infantry; they were an adjunct to that arm. For Congress, the question of a separate tank service became one of economics. Could the government afford an independent tank organization in view of the reduced postwar military budgets? Congressman Harry E. Hull of Iowa presented the problem as follows: “I can see how perhaps in the case of war there might be some need of a separate organization for tanks, but I am unable absolutely to see any reason during peacetime for the creation of the overhead that would have to be established to give you a separate organization.” Evidently, the majority of Congress agreed with Mr. Hull. Section 17 of the National Defense Act, as amended by Congress on 4 June 1920, assigned all tank units to the infantry. In tactics, as well as organization, the reorganization of 1920 had a tremendous impact on tank development. Under infantry control, tanks naturally had to conform to infantry tactics, which meant continuing the close support mission of World War I. Independent tank attacks had no place in infantry doctrine. A conference held by the General Service Schools at Fort Leavenworth, Kansas, in October and November 1921, discussed the organization and tactics of infantry tanks. The conference report, together with comments elicited from other officers and included in the report, indicated post-1920 thought on the use of tanks. To secure close cooperation between tanks and infantry, the report proposed assigning light tank companies as organic components of infantry divisions. Additional tank units would compose a GHQ reserve. This would ensure the maximum use of a limited number of tanks. GHQ tanks, distributed in depth, would be allotted to the corps delivering the main assault. Terrain and the mission of the assault divisions dictated the distribution of available tanks. Departing from established doctrine, the conference suggested the allotment of additional machine guns to each tank company. In a defensive situation, these units could serve as machine gun companies. Again departing from normal doctrine, the conference maintained that in certain situations tanks might successfully assist horse cavalry in performing its missions. Criticism of this report came from several War Department sources. On 9 December 1921, the Tank Board met at Fort Meade to consider the report of the General Service Schools conference. This board criticized the proposal for using tank companies as machine gun units. Tankers required additional training, Brigadier General S. D. Rockenbach, commandant of Tank Corps, defended the tanks’ performance and stressed the need for improving them. 15 equipment, and manpower to carry out any dual missions. The board maintained that tanks were offensive weapons only. According to the Infantry Board, the number of tanks available during wartime would not be sufficient to maintain division tank companies, as well as GHQ tank units. Furthermore, divisions might not operate in terrain suitable for employment of tanks. Tank companies organic to infantry divisions might prove more of a burden than an asset. Writing to the commandant of the General Service Schools, the adjutant general charged that instructors at the conference failed to deal with existing organization, units, and arms. Instead, they made unauthorized assumptions regarding the tank service. The adjutant general said that uniformity of tactical doctrine cannot exist unless all schools based their teachings on existing organization. Tactically, tanks served as an auxiliary of the infantry. According to the adjutant general, any discussion of tank tactics had to begin with that premise. Even before the reorganization, the Army took steps to ensure closer cooperation between tanks and infantry. Early in 1920, the Secretary of War, in response to a request by the 1st Division commander, General Summerall, assigned one tank company to each infantry division and assigned one battalion of tanks to the Infantry School at Fort Benning. After reorganization, the units retained at Camp Meade included the 16th Tank Battalion (Light), the 17th Tank Battalion (Heavy), and a maintenance company. Meade was also the location of the Tank School and the hub of postwar tank activities. In the event of war, Meade would have become a mobilization, training, and replacement center for tank units. Four light tank companies and six separate light tank platoons were the remaining tank units assigned to Regular Army posts. In addition, the National Guard had fifteen light tank companies located throughout the United States. All tank organizations, National Guard and Regular Army, were organic to infantry divisions. Lack of funds restricted, but did not halt, the postwar activities of American tank units. For fiscal year 1921, Congress appropriated only $79,000 for tank units. During the war, tank crews operated their machines for the entire day, but peacetime budgets dictated that tanks be driven for a few hours at most because of a lack of funds to buy gasoline. Despite the inconvenience caused by tight budgets, tank units conducted important training and attempted to stimulate interest in tanks. A letter from First Lieutenant Eugene F. Smith, platoon leader of the 1st Platoon, 9th Tank Company at Fort Devens, Massachusetts, to now Colonel Rockenbach aptly reflected the difficulties and nature of tank training during the twenties. Smith’s platoon moved from winter quarters to Fort Devens between 12 and 17 May 1924. Upon arriving at its training area, the platoon constructed a tank park to house and protect its vehicles. Beginning on 9 June and continuing for three weeks, the tanks helped in clearing trees and land for a drill field. This was valuable experience because it gave all hands an opportunity to drive the tanks under difficult conditions. After completing the preparation of their training area, the platoon held a test mobilization on 3 July. Despite only 24 hours notice, the test went well. From 7 to 9 July, two tanks of the platoon assisted the 5th Infantry in conducting demonstrations for an Elks convention in Boston. During the second and third weeks of July, the platoon assisted in the summer training of the 26th Tank Company of the Massachusetts National Guard. Several reserve tank officers trained with the platoon from 21 July until 2 August. Tactical exercises with infantry regiments constituted the unit’s primary activity in the latter part of July. On 15 and 16 July, the unit participated in field problems with the 13th and 5th Infantry Regiments, which served as part of the regiments’ annual tactical inspections. During both exercises, the tanks moved about eight miles under their own power and impressed the in-At the end of World War I, 100 Mark VIII tanks were collected at Fort Meade. At that time, the United States had almost 3,000 Mark VIIIs that had cost $85,000 each to build. 16 Photo: Robert J. Icks Collection fantry officers present with their ability to keep up with the march column. On 24, 28, and 31 July, Smith’s platoon participated in the tactical inspection of the 18th Infantry Brigade, which was observed by the I Corps commander and some War Department officials. To advertise the mobility and strength of tanks, the platoon conducted a demonstration for the visiting dignitaries. One tank crossed a trench system, drove across abridge, knocked down a tree, and then returned to the starting point. Smith noted, “We received some very good publicity in the Boston papers because of it.” The platoon held a demonstration of tank-infantry coordination in an attack for ROTC [Reserve Officer Training Corps] and Organized Reserve Corps personnel on 1 August. Following this exercise, several officers expressed their surprise that tanks could move so rapidly and assist the attacking infantry so well. More than just training his own men, Smith attempted to publicize the tank and impress other officers with its possibilities. The performance of the tanks in these summer maneuvers convinced many officers that they could rely on tanks in any combat situation. Smith concluded his letter to Rockenbach, “They don’t have to know that on one problem we had to stop and put anew fan belt on one tank, anew water pipe from the pump to the radiator on another, and stop every half mile and fill the radiator on another because it sprang a bad leak.” The most important tank activity of the twenties was the Tank School at Fort Meade. Among its more important functions, the school trained personnel for tank units such as Lieutenant Smith’s platoon. Although the enlisted men received instruction only in their specialties, the officers took a more comprehensive course. Included in the officers’ program was instruction on motors, ignition systems, battery maintenance, vehicle chassis, light tanks, heavy tanks, weapons, tank marksmanship, tank combat practice, tank history, tank organization, tank tactics, reconnaissance, intelligence, and chemical warfare. The courses were a balance between theory and practice. The National Guard and Reserve officer courses began in March of each year and continued for 3 months. The Regular Army officer course was of 10 months’ duration. Specialty schools for enlisted men lasted about 3 months. After graduation, the officers served a tour of several years with a tank unit. Most of the enlisted students came from one of the units at Meade and then returned to their former units upon graduation. But the type of training received by the men created some problems. The skills developed at the school were valuable in a society becoming rapidly motorized and many Tank School graduates left the service to take higher paying civilian jobs. To retain trained personnel, the Army began to assign students, who had at least 2 years remaining on their enlistments, to the school. Another activity located at Meade and closely associated with the school was the Tank Board. Originally organized in 1919 as the Tank Corps Technical Board, this body conducted tests, undertook studies, and made recommendations concerning tanks, tank equipment, tank unit transportation, and similar technical matters. Following the reorganization in 1920, the board disbanded until 1924. In October of that year, the commandant of the Tank School, with the approval of the chief of infantry, appointed four permanent members of the Tank Board. This board cooperated with the Tank School, the Ordnance Department, and other agencies concerned with improving tank development. Army Regulation 75-60, Infantry, Tank Board, 30 April 1926, reorganized the board. Rather than four permanently assigned officers, the board now consisted of the commandant of the Tank School, three officers designated by the chief of infantry, and one officer representing the chief of ordnance. In 1929, the chief of infantry, on recommendation of the president of the board, named a recorder and two other members. Similar to the Infantry Board, the Tank Board became apart of the Office of the Chief of Infantry. For initial equipment requirements, the Tank Board prepared performance specifications. Upon request of the chief of infantry, the proper supply facility procured the item and sent it to the board for tests. The board exercised a coordinating role between the tank troops and the supply agencies. Following the conclusion of tests, the board issued a report on the acceptability of the particular piece of equipment. Among the items considered by the Tank Board were communications systems, maintenance equipment, accompanying guns for tanks, a trench-digging tank, tank machine guns, and development of new tank models. Members of the board and the test officers worked on projects individually. At frequent meetings, the board as a whole reviewed and reported on the individual projects. The postwar years were both a time of transition and a period of stagnation for American tank development. Although the 1920 reorganization changed the organizational structure of the Tank Corps, small postwar military budgets limited activities. Among other things, this hindered production of new, improved tanks. But a number of officers retained an interest in tanks. They wrote for military periodicals, tried to impress their fellow officers with the capabilities of tanks, and like Lieutenant Smith, attempted to “advertise” tanks. By the end of the decade, the Army was contemplating more positive steps for improving the American tank service. A six-ton tank crashes through old barracks at Fort Meade. Demonstrations such as these were organized by tank enthusiasts to impress upon the public the usefulness of the tank. Despite favorable newspaper reports, funds provided were scanty. 17 Photo: Robert J. Icks Collection

By the latter part of the twenties, as the mechanical capability of the tank increased, military officials became more farsighted about its use. Increased mobility and heavier firepower enabled tanks to assume a more independent role. The chief of infantry and thus the officer having operational control over American tanks, Major General Robert H. Allen wrote in 1927, “My studies at the General Service Schools at Fort Leavenworth have convinced me that the tank was the only new ground weapon born during the World War that would, in future wars, play a role as conspicuous as the airplane, being the only weapon that could be relied on to overcome the machine gun and prevent a recurrence of the stabilized condition of ‘trench warfare’ similar to the Western Front.” Even the cavalry saw possibilities for tanks. In 1927, Major General Herbert O. Crosby, the chief of cavalry, recommended incorporating tank units into cavalry divisions and assigning antitank weapons to cavalry regiments. Colonel Samuel Rockenbach, commander of the infantry tank service, proposed that the cavalry and other branches, as well as the infantry, contribute to tank development. He said, “I submit that the recent developments by the British will have an effect in modifying our ideas in regard to tanks and that the role of tanks is no longer a special weapon for infantry, but that it is just as important to cavalry divisions, corps, and the Army.” The British efforts, not the prod-ding by Americans, precipitated an important change in American tank development. In early 1927, Secretary of War Dwight Davis witnessed the maneuvers of the British Experimental Mechanized Force at Salisbury Plain. This force, which was composed largely of tanks and other cross-country mechanized vehicles, impressed him so much that later in the year he ordered the organization of a similar American unit to serve as a military laboratory. Including troops from all branches, infantry, cavalry, tanks, artillery, air, ordnance, and supply, the force would be self-sufficient. Davis authorized the commanding officer to ignore existing regulations concerning organization, armament, and equipment. By conducting tests, the War Department sought to develop proper equipment and correct doctrine for the mechanization of additional units. General Charles P. Summerall, then chief of staff, ordered the operations and training section (G3) of the general staff to undertake a study of mechanization, which would serve as the basis for the organization of a temporary experimental mechanized force. On 30 December 1927, Summerall approved a preliminary G3 report for the organization of that force. Elements of the mechanized force would organize and train at their permanent stations and then assemble at Fort Meade during the summer of 1928. An infantry tank officer and former commandant of the Tank School, Colonel Oliver Eskridge, commanded the Fort Meade force. Units assigned to the experimental mechanized force included the 16th and 17th Tank Battalions, one separate tank platoon, one battalion of the 34th Infantry, an armored car troop, one battalion of the 6th Field Artillery, an engineer company, a signal company, a medical detachment, the 1st Ammunition Train, a chemical warfare platoon, an ordnance maintenance platoon, and a provisional motor repair section. By 3 July 1928, the entire force had assembled. Major Douglas T. Green, plans and training officer for the unit, outlined the program of instruction, training, and tactical exercises. From 9 to 14 July, training would consist of instruction on Chapter III: The Experimental Mechanized Forces (Reprinted from the May-June 1969 issue of ARMOR ) equipment, inspection by the commanding officer, and instruction in short route marches to determine proper methods and procedures for road travel. Following this preliminary training, the entire organization would make a 5-day march to Aberdeen Proving Ground and Carlisle Barracks, and then return to Meade. Such an exercise would give valuable experience in determining proper grouping in march columns; economical rates of march; means of command, supply, and reconnaissance while on the march; and methods of conducting night marches. During the latter part of July and into August, the unit would conduct tactical training for offensive operations. From 27 August until 15 September, the schedule called for the solution of field problems to test the tactics taught during the preceding training period. Although the unit generally followed the training program, difficulties arose. Obsolete wartime equipment, which often broke down, proved the greatest handicap. Insufficient equipment and improper balance made the force a poor demonstration unit. Colonel Eskridge requested that the War Department cancel a proposed visit by foreign military attachés because he feared that a poor performance by his troops might embarrass the entire Army. Despite its imperfections, the experimental mechanized force could not be considered a failure. Both Eskridge and the assistant chief of staff G3, Brigadier General Frank Parker, agreed that the unit provided useful technical and tactical information. By the end of September 1928, the force had accomplished its mission. Therefore, on 19 September, Parker recommended to the chief of staff that the unit be disbanded as originally planned. General Summerall approved this on the twentieth. After 1 October, all the component units of the experimental mechanized force returned to their home stations. In the spring of 1928, while plans progressed for the organization of the experimental unit, the War Department began planning for along-range mechanization program. General Parker submitted a report in March 1928, which emphasized the necessity of firepower and mobility to achieve success in modern warfare. Parker regarded tanks as a means of restoring the power of decision to battle. During World War I and after, tanks were tied to the infantry, thus reducing their mobility and shock effect. Instead of this, Parker believed that they should drive forward and attack hostile reserves and rear installations. Not adopting an extreme pro-mechanization position, he considered entirely mechanized armies inconceivable. They were prohibitively expensive, logistics support would be difficult, and machines could not operate in all kinds of terrain and weather. But mechanized units were valuable additions to any offensive operation. The potential uses of mechanized units outlined in Parker’s report included operating as the spearhead of an important attack, as a counterattack force, and as the advance or flank guard of strategic formations. Proper organization was necessary for any mechanized force. These required sufficient striking power to penetrate the enemy’s defense and disorganize his reserves. But mechanized units could not be so large as to become unwieldy. Tank companies comprised the principal striking power of any mechanized force. As envisaged in Parker’s report, light tanks, the leading element in an assault, attacked weak points in the defense; enemy flanks were particularly vulnerable. Self-propelled artillery and medium tanks supported the advance by overcoming strong points and widening gaps in the enemy’s line. Infantry, brought forward in mechanized vehicles, consolidated the ground captured by the tanks. Supply, maintenance, and other support elements were mechanized in order to keep up with the advance. In concluding his report, Parker made several specific recommendations for the long-range development of mechanization in the United States Army. He proposed that procurement of equipment for mechanized units, including light and medium tanks, a reconnaissance car, cross-country vehicles for infantry and support units, and self-propelled artillery, commence during the 1930 fiscal year. Congress had to pass the necessary legislation to establish one permanent mechanized unit during fiscal year 1931. This unit would use both modern and obsolete equipment. During 1931 and 1932, the obsolete equipment would progressively phase out. Secretary of War Davis approved Parker’s report as the basis for future development and organized aboard of general staff officers to prepare the details for future action. Among those appointed to this board was Major Adna R. Chaffee Jr., a cavalryman and a member of the G3 section of the War Department General Staff. From the time of his assignment to G3 in June 1927 until his death in the summer of 1941, Chaffee remained one of the leading American advocates of mechanization. Before 1927, Chaffee knew nothing about tanks. Realizing that G3 was beginning studies on mechanization, Chaffee learned all he could about the subject. At Rochester, he witnessed the demonstration of anew tank, capable of 18 miles per hour, built by James Cunningham and Sons. Chaffee also saw a test of the Christie tank, which could go 42 miles per hour. These demonstrations convinced him that tanks should not be tied to the infantry, advancing at a walking pace. The maneuvers of the British mechanized units also aroused his interest. At this time, a friend of Chaffee’s, Charles G. Mettler, was serving as military attaché to Great Britain. When Mettler visited Washington in 1927, Chaffee questioned him about British efforts in mechanization. Some years later, Mettler recalled, “He loaded me with a terrible list of things he wanted to know and expected me to find out for him when I returned to London.” His own observations and information received from sources, such as Mettler, stimulated Chaffee to promote mechanization. Although not immediately the moving force in American mechanization (he ranked sixth in seniority on the Mechanization Board appointed in 1928), Chaffee’s influence gradually increased and his interest never waned. But the development of mechanization cannot be attributed to any one person. Progress was slow and the result of the efforts of many officers. Colonel Adna R. Chaffee 19

Initially, the 11-man Mechanization Board met on 15 May 1928, in Room 346 of the State, War, and Navy building. Thereafter, it met from time to time as work demanded. Members of the board, who were from all branches of service, witnessed demonstrations of new tank models and the exercises of the experimental mechanized force. In its final report, issued in October 1928, the board reached conclusions about mechanization similar to General Parker’s report. The group also outlined a tentative program for future development. The board recommended the organization of a unit similar to the recently disbanded experimental mechanized force to serve as a technical and tactical laboratory. A force of 131 officers and 1,896 men would be organized into a headquarters, one light tank battalion, two mechanized infantry battalions, one field artillery battalion, an engineer company, and a medical detachment. In order that tactical doctrine would keep pace with mechanical developments, the board proposed supplying the force with the latest equipment. Although not recommending formation of a separate branch, the board emphasized the necessity of forgetting branch rivalries and traditions to make progress in the field of mechanization. With one exception, all of the branch chiefs concurred in the report. On 31 October 1931, the secretary of war approved the recommendations, but due to budgetary considerations, postponed organizing a mechanized force from fiscal 1930 until fiscal 1931. Major General Stephen O. Fuqua, the chief of infantry, was the exception among the branch chiefs concurring in the report. Earlier, he had disagreed with the conclusions of General Parker’s report on mechanization. Fuqua’s criticism was based strictly on branch rivalry; exactly the sort of thing the Mechanization Board wanted to avoid. A separate mechanized force threatened the complete control over tanks, which the infantry had since

1920. Fuqua protested to Parker, “The tendency in this study to set up another branch of the service with the tank as its nucleus is heartily opposed. It is as unsound as was the attempt by the Air Corps to separate itself from the rest of the Army. The tank is a weapon and as such it is an auxiliary to the infantryman, as is every other arm or weapon that exists.” According to Fuqua, the authority for tank development should remain where it was — with the chief of infantry. Despite the general’s protests, the War Department proceeded with its plans for mechanization. In his 1930 annual report, Chief of Staff General Summerall, reaffirmed the Army’s commitment to proceed with formation of a mechanized force. He declared, “From being an immediate auxiliary of the infantry, the tank will become a weapon exercising offensive power in its own right.” Recognizing the importance of a suitable tank force, Summerall ordered that the proposed mechanized force become a permanent unit, not a temporary or experimental organization. But the development program, so carefully planned, ran into unexpected difficulties. The inability of the Ordnance Department to produce a tank acceptable to the Tank Board, and a lack of funds, delayed the organization of the mechanized force. Failure to produce a suitable tank was particularly crucial because tanks formed the nucleus of the force. Everything else might disappear and the tanks could still accomplish at least part of the mission; however, without tanks, the remainder of the force was useless. Until the late twenties, the Army used surplus wartime equipment. As the experience of the experimental mechanized force indicated, this equipment was obsolete. Unfortunately, the advent of the Great Depression paralleled the decline of wartime materiel. Retrenchment and stabilization of military budgets made a modernization and reequipment program difficult. The War Department had to determine how best to maintain the Army with limited funds and availability of funds often affected policy. Ordnance Department estimates for fiscal year 1932 reflected this trend. Priorities for the submitted ordnance budget of $2.4 million were for limited service tests and procurement of semiautomatic rifles, 3-inch antiaircraft guns, and as many tanks as possible with the remaining money. Colonel Van Voorhis and Major Sereno Brett, speak into a Paramount Sound News microphone at Fort Eustis in 1931. To the left of the tree stands Major R. W. Grow who later, as a major general, commanded the 6th Armored Division in World War II. 20 Photo: MG R. W. Grow Collection

When the final War Department budget directive reduced the amount to $1 million, the general staff, which determined priorities, decided to use the money for the highest priority items: the rifles and only a few tanks. The staff decided that progress in tank development warranted the purchase of only a few tanks to test tactics and keep up with the latest technology. Because of these decisions, the mechanized force, when finally organized at Fort Eustis in November 1930, used unsuitable, obsolete equipment. On 24 November 1930, Colonel Edward O. Croft, the acting assistant chief of staff, G3, selected units for the force. Company A of the 1st Tank Regiment, equipped with six World War Renaults, five modernized Renaults, and four T1E1 tanks, formed the nucleus of the unit. One armored car troop with ten vehicles served as the reconnaissance element. One battery of the 6th Field Artillery, equipped with obsolete service trucks, not self-propelled guns as the War Department studies advocated, provided fire support. Equipment problems also plagued the engineer company assigned to the force as its transportation initially consisted of horse-drawn wagons. Fifteen light tanks, 10 armored cars, seven tractors, 66 trucks, 22 automobiles, and less than 600 men composed the Mechanized Force. General Summerall selected Colonel Daniel Van Voorhis as commander of the unit. Van Voorhis, a career cavalry officer and recent (1929) graduate of the Army War College, had no previous experience with tanks. As executive officer, Summerall picked Major Sereno E. Brett, a former wartime commander of the 304th Tank Brigade. During September 1930, Van Voorhis, Brett, and Chaffee, now head of the G3 troop training section, visited Aberdeen Proving Ground, Holabird Quartermaster Depot, and Fort Eustis. They conferred with officers at these posts relative to the equipment and organization of the Mechanized Force. The chief of staff based the tactical and training missions of the force on the findings of these officers. In combat, the Mechanized Force would execute missions presenting an opportunity for tactical and strategical mobility and quick, hard striking power. The training mission of the unit was to determine the proper tactics involved in the operation of fast tanks with other mechanized and motorized arms. From 1 November until 31 December, the force would organize and conduct individual training. Unit training and combined drills to perfect teamwork followed. Beginning in March and continuing until the end of the fiscal year in June, the unit planned to hold field exercises and maneuvers with troops of other arms. During the period from 1 November 1930 until 30 June 1931, the Mechanized Force carried out its proposed training schedule. The 34th Infantry (Motorized) and the Air Corps Tactical School assisted in some of the maneuvers. Operations consisted of command post exercises, field problems, maneuvers, demonstrations, and ceremonies. Among the exercises were night tactical and strategic marches, offensive combat against entrenched infantry, offensive operations against another mechanized force, attacks involving wide turning movements, seizure of key positions, and operations as a covering force for a larger unit. All of the missions executed by the Mechanized Force emphasized its mobility. Traditionally, cavalry was the branch of mobile warfare, but during the twenties, the cavalry had done little in the field of mechanization. Recognizing these facts, General Douglas MacArthur, who became chief of staff on 21 November 1930, ordered the Mechanized Force disbanded and directed all branches, in particular the cavalry, to mechanize as far as possible. This decision affected the development of American mechanization down to the organization of the Armored Force in 1940. Bibliographical Note Material for Chapter I of this article came from a number of sources. The great bulk was derived from materials in the National Archives at Washington. Operations reports of the various tank units, a history of the 304th Brigade, and the AEF Adjutant General File were all found in Record Group (RG) 120, which contains the complete AEF records. The War College Division File (RG 165) was also helpful for information on planning. Another good source included volumes in the U. S. Army in the World War, 1917-18 series published by the Department of the Army in 1948. The volumes, entitled Organization of the AEF and Reports of the Commander-in-Chief, AEF Staff Sections and Services contained reports by Rockenbach and Patton on tank activities during the war. A pamphlet published in 1918 by the War Plans Division, Instructions for the Training of the Tank Corps in France, was good for data on training. Among the secondary sources used were J. F. C. Fuller’s Tanks in the Great War (1918), Arch Whitehouse’s Tank (1960), and Ladislas Farago’s Patton (1963). The quote from Douglas Haig came from E. W. Shepard’s Tanks in the Next War published at London in 1938. The author also used several sources in preparing Chapter II. Foremost were records in the National Archives. Departmental memos, reports from the various conferences considering tanks, and some personal correspondence were found in Record Group 94 (The Adjutant General File) and Record Group 177 (The Chiefs of Arms File). Other primary sources included Congressional documents such as the Hearings Before the House Military Affairs Committee, Vol. 1 (1919) and the Reorganization of the Army Hearings, Vol. I (1919); both of these volumes were published from the records of the 66th Congress, 1st Session. War Department annual reports also provided valuable facts and figures about tank units. Three Infantry Journal articles furnished information on tank activities during the twenties: William E. Spei del, “The Tank School,” June 1925; “The Tank Board,” August 1926; and Ralph E. Jones, “The Tank School and Tank Board.” The Farago biography of Patton and Eisenhower’s At Ease! (1967) gave useful insights into the activities of these officers. Material at the National Archives also constituted the primary source for Chapter III. Memos by branch chiefs, assistant chiefs of staff, and the adjutant general were found in the Adjutant General File, Record Group 94. Operations reports of the mechanized units and the report of the Mechanization Board were also in this file. Additional material was found in RG 177, the Chiefs of Arms File. General Chaffee’s obituary in the April 1942 West Point Assembly, written by Charles G. Mettler, provided some useful information. “The Impact of the Great Depression on the Army, 1929-36,” an unpublished dissertation from Indiana University by John W. Killigrew, was also very good. War Department annual reports contain data on tank development and outline overall policy. TIMOTHY K. NENNINGER is currently serving as the chief of the Archives II Textual Records Reference Staff at the National Archives. He has been with the National Archives since 1970, where he has had extensive experience working with military and naval records. From 1994 to 1997, he was an analyst on the World War II Working Group of the joint U. S.-Russia commission on prisoners of war/missing in action (POW/ MIA), and was the principal author of the working group’s report, “The Experience of American POWs Liberated by the Soviet Army, 1944-45.” He has served in various positions throughout his career, to include chief of Modern Military Records; supervisory archivist with the Archival Allocation and Records Evaluation Staff; chief of the Military Projects Branch; archivist with the FBI-National Archives records appraisal task force; and co-director of the National Archives conference “Soldiers and Civilians: The U. S. Army and the American People” (1979). From 1997 to 2005, he was vice-president, and later president, of the Society for Military History. During 1987-88, he was the John F. Morrison Professor of Military History at the U. S. Army Command and General Staff College, Fort Leavenworth, Kansas. A graduate of Lake Forest College, he received his M. A. and PhD degrees in history from the University of Wisconsin-Madison, where his specialization was the American military, afield in which he has published a number of works. 21