U.S. Army Observes 75th Anniversary of Armored Force Compiled by Lisa Alley

U. S. Army Observes 75th Anniversary of Armored Force Part 1 of 2 The Army’s armored force was official ly “born” July 10, 1940, quietly revolu tionizing modern methods of war. Be fore armored warfare, American troops had limited ability to speedily and decisively maneuver to and penetrate the enemy’s defensive lines. World War I Before World War I, horse-mounted cavalry performed what is now the tank’s role: maneuvering and breaking through enemy infantry to attack lines of communication and means of sup port in the rear. The entrance of ma chineguns and closed fronts on the battlefield made cavalry too vulnerable for this task, while armor was ideal for it. Modern armored warfare began with the need to break the stalemates forced on commanders fighting on the Western Front caused by the effectiveness of entrenched defensive infantry armed with machineguns (trench warfare). Any sort of advance was interminably slow and caused un acceptable, massive casualties. The tank’s development, then, was moti vated by the need to return maneuver to warfare, and the only way to do so was to protect Soldiers from smallarms fire as they were moving. The United States established its Tank Corps in 1918 using French Renault FT light tanks and British Mark V and Mark V heavy tanks. Some officers like GEN Dwight D. Eisenhower and GEN George S. Patton Jr. emerged from the Great War as avid proponents of con tinuing and developing an American Armored Force. Interwar years: 1920s-1930s After World War I, Congress restructured the Army based on a review of its wartime actions. The National Defense Act of 1920 defined the Army’s organization and operation throughout the interwar period, and it abolished the separate Tank Corps. The tank’s wartime infantry-support role suggested its alignment with the dismounted branch. Therefore, the infantry received exclusive responsibility for developing new tank designs and the related training and doctrine. While the 1920s would witness significant innovation in tank usage by other nations, American tank development occurred within the relatively narrow confines of the infantry’s mission of seizing and holding ground. The infantry developed the tank as one of several support weapons for the ri fleman. In particular, it sought the close integration of tanks and infantry at the small-unit level. This capability suited infantry needs and constituted an important role for the tank. In the early 1920s, COL Samuel Rockenbach – who led the tank force in World War I – supported efforts to build a more powerful and reliable medium tank. However, prototype models tended to be too heavy, and the desired balance of firepower, mobility and protection proved beyond the technology avail able. This failure, coupled with the Ar my’s interest in fighting a war of ma neuver rather than in trenches, shifted tank-design emphasis to light, fast tanks that leveraged major advances in suspension, track and engines. British experimentation with the use of tanks in multiple roles finally prompt ed similar testing in the United States. Between 1928 and 1931, the Army cre ated two experimental units that mixed tanks with other combat and support elements – the Experimental Mechanized Force at Fort George G. Meade, MD, in 1928, and the Mechanized Force at Fort Eustis, VA, in 1930. Each one comprised a motley collection of vehicles and weapons with lim ited tactical value. However, the expe rience these organizations acquired prompted Army-wide discussion of Figure 1. LTC George S. Patton Jr., 1st Tank Battalion, and a French Renault FT tank, Summer 1918. (Photo by U. S. Army Signal Corps, World War I Signal Corps Photograph Collection, http://www.army.mil/-images/2007/04/22/3578/army. mil-2007-03-28-152527.jpg) new roles and tactical organizations for the tank. The notion of a separate mechanized arm emerged, but in the absence of more funding and personnel, the Army could only create such a force by diverting resources from the existing combat arms. This course of action met with resistance that inten sified with the Great Depression’son set and congressional unwillingness to increase military spending. The impasse between creating anew mechanized arm and resourcing was resolved in 1931 by Army Chief of Staff GEN Douglas MacArthur. In anew mechanization policy, he directed the combat arms to pursue separate mech anization efforts using their own re sources. No longer would each combat arm face the specter of losing funding and personnel to a rival organization. This decentralization proved less efficient than the centralized mechanized programs of Germany and Russia, but MacArthur’s policy ensured that the Army would adopt mechanization rath er than be threatened by it. The new mechanization policy had little effect on infantry tank development, but it permitted the Cavalry to begin experimenting with tank usage. Throughout the 1920s, the mounted arm had to limit its interest in motor vehicles to armored cars, which proved mechanically fragile and road-bound. In 1931, however, the Cavalry estab lished the 7th Cavalry Brigade (Mechanized). Initially little more than a paper organization, the brigade included 1st Cavalry Regiment (Mechanized). This unit exchanged its horses for vehicles and relocated from the Texas border to Fort Knox, KY, in 1933. Knox was one of the largest installations in the United States, but other than summer training by National Guardsmen and Reservists, it lay unused. With 1st Cavalry’s arrival, Fort Knox began its long association with mechanized development. The 1st Cavalry initially served as a tac tical laboratory to help determine the optimal organization, doctrine and ma teriel for a Cavalry organization built around vehicles. Through maneuver participation, field exercises and anal ysis, its personnel evolved the unit into a flexible organization, capable of per forming the full range of Cavalry mis sions. By the mid-1930s, the regiment had been joined at Fort Knox by 13th Cavalry Regiment (Mechanized) and at tachments of artillery and engineers. Collectively, these forces transformed 7th Cavalry Brigade (Mechanized) from a paper organization into a powerful combined-arms force. Tanks assigned to this unit received the designation “combat cars.” This nomenclature change ensured that the mechanized cavalry adhered to the letter of the National Defense Act of 1920 and left the infantry’s exclusive responsibility for tanks unaltered. Cavalry doctrine envisioned mounted elements operating in small groups dispersed over abroad frontage. To offset the vulnerability of small numbers of tanks operating alone, they were sup ported by troopers, engineers and mortar teams. Continued experimen tation and field exercises led to the in tegrated action of these elements and the beginnings of modern American combined-arms tactical doctrine. Rapid movement of these teams rein forced Cavalry emphasis on outmaneu vering the enemy rather than engaging in sustained and costly firefights. Hence, mobility and speed became critical attributes. In armored-vehicle design, the mechanized cavalry consis tently opted for speed and mobility over firepower and armor protection. Organizational and tactical concepts that slowed operational tempo were discarded. In its efforts to coordinate the actions of multiple fast-moving combined-arms teams, 7th Cavalry Brigade (Mechanized) revolutionized command-and-control procedures. Visual signals and wire-based communications proved too slow to facilitate rapid decisionmaking and sustain the high operation al tempo desired. Therefore the mechanized cavalry embraced widespread radio usage. It established radio nets that conformed to a unit’s tactical organization and abandoned the Army’s rigid emphasis on encoded transmis sions. Before a mission began, key par ticipants were briefed on the overall objectives and their specific tasks. When operations began, subordinate leaders received short radio messages sent in the clear to update them on changing conditions. While these transmissions might be intercepted, mechanized-cavalry personnel believed that rapid communication, coupled with fast action, outweighed potential security risks. Moreover, the cryptic nature of radio traffic provided a degree of signal security, since an opponent lacked the context of the mission order. The pioneering efforts of 7th Cavalry Brigade (Mechanized) at Fort Knox marked the introduction of mis sion-type orders and fragmentary orders into the Army. In maneuvers and field exercises, the mechanized cavalry discovered it could increase its battlefield effectiveness by altering the composition of its combined-arms teams to meet changing tactical conditions. The 7th Cavalry Brigade (Mechanized) and its subordinate regiments rarely operated as a single mass. Instead, they operated as a col lection of combat teams, each one organized according to its objective, expected enemy resistance and terrain. The composition of these teams changed according to the tactical situation and gave the mechanized cavalry a high degree of organizational flexibility. Task organization marked a depar ture from the Army’s traditional reliance on rigid tactical groupings and marked the foundation for the later World War II-era combat command. By comparison, in the Soviet Union during the early 1930s, Red Army and German officers collaborated in devel oping tanks based on second-generation vehicles using turreted main weapons, and experimented with dif ferent chassis configurations and drive trains. One important acquisition for the Red Army turned out to be the purchase of a T3 chassis from U. S. design er J. Walter Christie, which served as the basis of the Soviet BT series of fast tanks. A development taking place shortly be fore World War II that influenced Soviet armored doctrine and tank design for a decade was the creation of the T-34. Developed on the Christie sus pension chassis and using sloped ar mor for the first time, the T-34 proved a shock to the German forces in World War II with its excellent combination of mobility, protection and firepower. Us ing wide tracks, the T-34 was also able to negotiate terrain in difficult weather conditions, something that persis tently dogged the German designs. Chaffee’s influence A principal player in U. S. tank develop ment was MG Adna R. Chaffee Jr.,1 an outspoken advocate of mechanization in the interwar years. He served on the American Expeditionary Forces staff in World War I. In 1927, Chaffee became a staff officer in the G-3 Section of the War Department General Staff, where he became immersed in the study of tanks and that year predicted mecha nized armies would dominate the next war. Through a personal friendship with the American military attaché to Britain, he acquired accurate informa tion regarding the latest British mech anized developments. In the 1930s, he became closely associated with mech anized-cavalry development, commanding 1st Cavalry and later 7th Cavalry Brigade (Mechanized). In 1940, he became the first chief of the Armored Force, shaping the nature of American future armored doctrine before his death in 1941. Chaffee helped develop appropriate training, equipment and doctrine dur ing the late 1920s through the 1930s. Assigned to 1st Cavalry Division in 1931, he continued to develop and experi ment with armored forces. Chaffee trained 1st Cav for the Fort Riley Maneuvers in 1934. In the maneuvers to Allegan, MI, in August 1936, 1st Cavalry traveled 400 miles in two days. Under COL Bruce Palmer, 1st Cavalry fought the Red Team against the Blue Team for the first time in a division-level ma neuver.2 In 1938, Chaffee assumed command of the reorganized 7th Cavalry Brigade, the Army’s only armored force. Chaffee battled continuously during the prewar years for suitable equipment and establishment of armored divisions. With the collapse of the French army in June 1940, Chaffee’s 1927 predictions of the importance of armored forces in modern warfare were confirmed. In the August 1939 Plattsburg Maneuvers, the largest American peacetime exercise to date, 1st and 13th Cavalry Regiments engaged in mock combat between two corps. The brigade leaders refined Cavalry doctrine, with tracked vehicles traveling at night, without lights, to take the major road center of Peru by surprise. Unlike the British use of a mechanized force to support infantry, 7th Cavalry Brigade at Plattsburg followed the German exam ple by preserving the separate organizational integrity of the mechanized force.3 Chaffee commanded 7th Cavalry Brigade (Mechanized) during the First Army Maneuvers of 1939. This event demonstrated how a fast-moving mechanized force could decisively influence a battle. The critical action oc curred when the unit conducted a 60- mile night roadmarch under blacked-out conditions to launch a dawn flank ing attack. The brigade burst into the rear area of the opposing force, creating enough mayhem to trigger the end of the maneuvers. “Chaffee certainly helped turn military opinion to support a strong armor force; his decade of quiet and consis tent leadership paid off in the Louisiana Maneuvers of 1940 and the found ing of the American armor force in July of that same year,” wrote John Crans ton in his article, “German and British Experimentation in 1920s-30s Inspired Emergence of U. S. Armor Force” (AR MOR, March-April 1995 edition). “However, Chaffee’s work in the 1930s, including successively expanded ma neuvers, in many ways built on founda tions laid earlier in Germany from 1918 until 1926 and, to a lesser extent, in mechanized maneuvers held in England after that time through 1938. Chaffee’s outstanding achievements by 1940 may well have evolved because of his knowledge of European prece dents. Throughout combined-arms ex ercises, he preserved the integrity of the mechanized and later of the armor force.” The 7th Cavalry Brigade went on to fight in the corps-level Louisiana Maneuvers of 1940, which were the largest peace time maneuvers conducted in the Unit ed States up to that time. Together with the recently arrived 6th Infantry Regiment (Mechanized), the brigade was attached to IX Corps. A provisional tank brigade from Fort Benning, GA, was attached to IV Corps. The two bri gades fought first against each other and then on the same side, with mech anized brigades emerging as clear win ners in the maneuvers. IV Corps em ployed the “triangular” division con cept with three regiments per divi sion.4 Within days of the end of First Army Maneuvers, Germany invaded Poland. The Nazis’ high-profile use of com bined-arms formations served to vindicate the tactical ideas 7th Cavalry Brigade (Mechanized) had developed and spurred efforts to expand that unit into a mechanized division. Increasing the Army’s mechanized might, however, suffered from lack of funds and mate riel. Only small numbers of new com bat vehicles were produced before

1939. Numerically, the most significant vehicle in the Army’s inventory re mained the Mark VIII heavy tank and an American version of the FT-17, both dating from World War I and obsolete. However, the interwar years did wit ness steady improvements in the reliability and durability of tracks, engines and suspension systems. By 1939, the prospect of another war in Europe led the Army to order the production of more than 300 M2A4 light tanks equipped with 37mm guns. For mech anization, this action signaled the end of the Great Depression’s lean years. Patton’s contributions Another U. S. Army figure with fore sight included Patton; in the interwar period, Patton5 was also a central figure in the development of armored-warfare doctrine in the U. S. Army. Pat ton began his interest in tanks during World War I while in hospital for jaun dice. There he met COL Fox Conner, who encouraged him to work with tanks in lieu of infantry. In 1917, Pat ton was assigned to establish the American Expeditionary Forces’ Light Tank School and trained tank crews to operate in support of infantry, promoting the Armored Force’s acceptance among reluctant infantry officers. Pat ton commanded American-crewed Re nault FT tanks at the Battle of Saint-Mihiel. After the war, Patton was given tempo rary duty in Washington, DC, in 1919 to serve on a committee writing a man ual on tank operations. During this time, he came to believe that tanks should be used not as infantry support but rather as an independent fighting force. Patton advocated the M1919 tank design Christie had created, a project shelved due to financial considerations. With Christie, Eisenhower, Chaffee and a handful of other officers, Patton pushed for more development of armored warfare in the interwar era. Patton was transferred in May 1927 to the Office of the Chief of Cavalry in Washington, DC, where he began to develop the concepts of mechanized warfare. A short-lived experiment to merge infantry, cavalry and artillery into a combined-arms force was can celled after the U. S. Congress removed funding. During maneuvers Third Army conduct ed in 1940, Patton served as an um pire, where he met Chaffee, and the two formulated recommendations to develop an armored force. When Chaffee was named commander of this force and created 1st and 2nd Armored Divisions, he named Patton command er of 2nd Armored Brigade, 2nd Armored Division. The division was one of few organized as a heavy formation with a large number of tanks, and Patton was in charge of its training. As Chaffee stepped down from command of I Armored Corps, Patton be came the most prominent figure in U. S. Armor doctrine, staging a high-profile mass exercise driving 1,000 tanks and vehicles from Columbus, GA, to Panama City, FL, and back in December 1940 – and again with his entire divi sion of 1,300 vehicles the next month. Patton earned a pilot’s license, and during these maneuvers he observed the movements of his vehicles from the air to find ways to deploy them effectively in combat. Patton’s impact on armored warfare and leadership were substantial, with the U. S. Army adopting many of his ag gressive strategies for its training pro grams following his death in 1945. The first American tank designed after the war became the M46 Patton. Interwar years: 1940s On May 10, 1940, German armored formations spearheaded an invasion of France, triggering that country’s sur render within six weeks. This conquest shocked the American Army, which had held the French military in high regard. However, through the efforts of the The tanks that equipped armored units reflected the armored divi sion’s intended role. This formation was designed to envelop enemy po sitions and operate throughout an opponent’s rear area. Tank designs therefore emphasized maneuver and mobility over firepower and armor protection. Indeed, light tanks constituted much of the early armored divi sions’ tank strength. The M3 light tank (Stuart), later upgraded to the M5, carried a 37mm gun, could achieve tactical speeds of 35 miles per hour and proved easy to main tain. However, as the war pro gressed and the armor and arma ment of German tanks and self-pro pelled guns increased, the light tank became increasingly vulnerable. It became relegated to reconnaissance-and-security roles, and its numbers within the armored division fell in favor of more medium tanks. The M4 medium tank (Sherman) be came the principal American tank of World War II. More than 70,000 were built during the war, equipping both American and Allied armies. Like the M3/M5 light tanks, it proved mechanically reliable and mobile. It became the workhorse of the U. S. Army, providing close infantry support, spearheading armored attacks, performing anti-tank mis sions and acting as auxiliary artil lery. However, its 75mm main gun lacked sufficient armor-piercing ability, and it sacrificed firepower and armor for greater mobility. Even when upgraded to a 76mm, the M4’s armament could not penetrate the frontal armor of the more heavily armored German tanks and assault guns. Therefore, standard tactics for a five-tank platoon engaging German Tiger and Panther tanks required one section to draw the Germans’ fire, while the other section maneuvered to the flank and engaged the German tanks from the side or rear. Such tactics were not morale-builders for tank crews. Nor could the M4’s armor protect it from the high-velocity 75mm and 88mm guns commonly carried on German tanks. In such engagements, American tank units relied on support from aircraft, artillery and tank destroyers. Efforts to field a more powerful tank finally resulted in the M26 (Pershing) heavy tank, but only 20 entered combat before the war’send. For most tank units, combined-arms tactics became vital to success against German armor. Adapted from the U. S. Army Armor School Pamphlet 360-2, This is Armor. M3 and M4 tanks during World War II Figure 2. M3 Stuart in the Tennessee Maneuvers.

American military attaché staff in Berlin, headed by MAJ Truman Smith from 1935-1939, the U. S. Army possessed considerable information regarding the organization and operation of the German panzer division. After France’s de feat, German armored trends became the standard of comparison for American mechanized development. The ab sence of American armored divisions and corps fueled interest in merging mechanized cavalry and infantry tank development under a single organization. The War Department responded by establishing the Armored Force July 10, 1940, as a “service test” to centralize mechanized development. This organi zation bore responsibility for building a credible American armored capability. Fort Knox, home of the mechanized cavalry, became the location of the Armored Force’s headquarters. Infantry tank units and 7th Cavalry Brigade (Mechanized) merged to form the 1st and 2nd Armored Divisions and the sep arate 70th Tank Battalion. The newly fledged Armored Force re flected the mechanized cavalry’s influ ence. Chaffee was selected as the first chief of the Armored Force, and other officers with Cavalry or mechanized-cavalry backgrounds served in key command positions. Consequently, the Armored Force stressed maneuver and speed in its operations. Armored divi sions would envelop the enemy and engage soft targets in his rear rather than engage in deliberate assaults upon his strongest positions. Tank-vs.- tank combat was to be avoided if pos sible since it wasted armored resourc es in costly firefights. The Armored Force also assumed responsibility for organizing and training separate tank battalions for infantry support, though its initial focus lay on the more powerful armored divisions and corps. Enter Devers Following Chaffee’s death, MG Jacob L. Devers assumed command of the Armor Center at Fort Knox and became chief of the Armored Force in August

1941. Under Devers, doctrine evolved into a combined-arms operational force consisting of primarily infantry, artillery and tanks, with tanks being the major maneuver component. Under this doctrine, U. S. tank crews of both armored divisions and General Headquarters (GHQ) tank battalions were taught to fight tanks in tank-on-tank engagements. At this time anew medium tank was beginning to come off the production line: the M3 Grant. But Devers lobbied, sometimes against the views of his superiors, for a still more heavily armored and better-armed medium tank, the M4 Sherman. Devers played an im portant role in the M4’s design, development and manufacturing, particular ly its engine and armament. The Detroit Tank Arsenal began turning out Shermans in Fall 1941. The reliable, versatile, low-cost M4 and its variants would prove to be the most-produced tank in the U. S. Army during World War II. Devers’ command was responsible for training some 225,000 soldiers. At the beginning of 1942, two armored divisions were operational, five were in training and two more scheduled to be activated in February. All seven of those armored divisions were activat ed in 1942. (Army planners called for the eventual formation of 16 armored divisions and 54 tank battalions.) Activity at Knox therefore accelerated. The Armored Forces’ Replacement Training Center gave arriving soldiers 12 (later 17) weeks of training before they were sent on to armor units. The Armored Force School provided advanced individual training in specific areas such as gunnery, field tactics, communications and maintenance. The Armored Force Officer Candidate School prepared selectees to serve as commissioned officers in Armor. With so many men undergoing training, existing bases were overwhelmed. De vers had to oversee a massive construction of barracks, facilities and in frastructure, particularly at Fort Knox. A large maneuver area where soldiers could train for desert warfare was also sorely needed. Devers sent Patton, then commander of I Armored Corps (which included 2nd Armored Division), to set up the Desert Training Center in the California-Arizona Mojave Desert. Devers was an articulate proponent of the Army’s emerging tactical doctrine of combined arms: infantry-artillery-armor-close air support. At his direction an updated, comprehensive (460 Figure 3. Crew from the M4 tank “Eternity” (7th Army) check their vehicle after landing at Red Beach 2 on July 10, 1943, during the Allied invasion of Sicily. The first Sherman in U. S. service, the M4A1, appeared in the North Africa Campaign. (Photo by Signal Corps (Osborne), http://www.army.mil/cmh-pg/ photos/WWII/ErlyYrs/WW2-ErlYrs.htm) pages) Armed Force Field Manual: Tactics and Technique FM 17-10 was writ ten, published and distributed in March 1942. Under anew table of organization and equipment (TO&E) he proposed, armored divisions were downsized. For all but the 2nd and 3rd Armored Divisions, the number of reg iments was cut from six to three: two tank and one armored infantry. In a first, at Devers’ insistence, a flight of light aircraft to be used for artillery spotting, recon and liaison was included in the new TO&E for each division. Devers’ conceptualization of combined arms caused friction between him and GEN George C. Marshall’s chief of staff, LTG Leslie J. McNair, who commanded GHQ and was in tactical charge of all U. S. ground forces. GHQ, however, specifically did not control the semi-autonomous Armored Force, which was considered provisional and would not become a full branch until 1950. In March 1942, when Marshall ordered a major reorganization of Army head quarters, McNair was named com mander of anew component, Army Ground Forces (AGF), which replaced GHQ. Relations between GHQ/AGF and the Armored Force were distant, with lines of authority and responsibility of ten unclear. This friction helped delay development of the M26 Pershing heavy tank.6 From mid-1943 to mid-1944, development of the 90mm uparmored T26 proto type continued to proceed slowly due to disagreements about the Army’s fu ture tank needs. Tank historians such as Richard P. Hunnicutt, George Forty and Steven Zaloga have generally agreed that the main cause of the de lay in the M26’s production was AGF’s opposition to the tank. The details of what exactly happened during this time vary by historian, but all agree that in September-October 1943, a se ries of heated discussions occurred over the issue of beginning production of the T26E1, which Devers advocated. Zaloga, in particular, identified several specific factors that led both to the de lay of the M26 program and limited im provements in the M4’s firepower.7 The Ordnance Department favored de veloping its own project, naturally: the 76mm gun, electrical-transmission T23. Theater commanders generally favored a 76mm-gun medium tank such as the T23 and were against the heavy 90mm gun tank Devers liked. However, most commanders were un aware of the testing done at Fort Knox of the T23, which had demonstrated reliability problems in the electrical transmission. Also, the new 76mm M1A1 gun approved for the M4 Sherman seemed to address concerns about firepower against German tanks, but all debaters were unaware of the 76mm gun’s inadequacy against the Panther tank’s frontal armor. McNair8 had agreed to production of the 76mm M4 Sherman, and he strong ly opposed the T26E1’s production. In Fall 1943, he wrote Devers, responding to Devers’ advocacy of the T26E1, and pointed out the theater commanders’ opinion: “There has been no call from any theater for a 90mm tank gun. … There can be no basis for the T26 tank other than the conception of a tank versus tank duel – which is believed unsound and unnecessary. Both British and American battle experience has demonstrated that the anti-tank gun in suitable number and disposed proper ly is the master of the tank. Any at tempt to armor and gun tanks so as to outmatch anti-tank guns is fore doomed to failure.... There is no indi cation that the 76mm anti-tank gun is inadequate against the German Mark VI (Tiger) tank.” Devers pressed on with his advocacy for the T26, going over McNair’s head to Marshall, and on Dec. 16, 1943, Marshall overruled McNair and authorized the production of 250 T26E1 tanks. Then, in late December 1943, Devers was transferred to the Mediterranean, where he eventually led the invasion of Southern France with 6th Army Group. In his absence, further at tempts were made to derail the T26 program, but continued support from Marshall and Eisenhower kept the production order alive. Testing and production of the T26E1 proceeded slow ly, however, and the T26E1 did not be gin full production until November

1944. These production models were designated as the T26E3. According to Hunnicutt, the Ordnance Department had requested production of 500 each of the T23, T25E1 and T26E1 in October 1943 and continued to press for production of 1,000 tanks. Louisiana Maneuvers At the time Devers took command of Fort Knox, the Armored Force had just two operational armored divisions: the 1st at Fort Polk, LA, and the 2nd at Knox. Both participated in the large-scale two-phase corps-vs.-corps GHQ 1941 Figure 4. An M26 Pershing T26E3 from Company A, 14th Tank Battalion, is transported aboard a pontoon ferry across the Rhine at Remagen March 12,

1945. The ferry was built by 1st Engineer Heavy Pontoon Battalion. (U. S. Army Signal Corps photo)

Maneuvers. These wargames, the Louisiana Maneuvers, were held in Louisiana and the Carolinas. Despite some successes, the maneuvers revealed ar mored-unit and equipment operation al deficiencies, plus a general lack of combat readiness. In particular, post-maneuver reports showed a vulnera bility of U. S. tanks to anti-tank fire. This bolstered McNair’s philosophy.8 Devers differed, countering that the number of tank kills credited to antitank gunners was unrealistic and bi ased. McNair continued to push for an independent tank-destroyer (TD) force. Devers argued that the best weapon against a tank was a better tank. Nevertheless, in November 1941, Marshall authorized creation of the TD force. (Battlefield experience would prove that Devers was right. In combat, TDs were mainly used as mobile artillery support. At the end of the war, the TD force was disbanded.) Patton’s exploits, meanwhile, support ed the proponents who said the Armored Force lent speed and agility. Patton led 2nd Armored Division during the Tennessee Maneuvers in June 1941 and executed 48 hours’ worth of planned objectives in only nine. During the September 1941 Louisiana Maneuvers, his division executed a 400-mile end run around the Red Army and “captured” Shreveport, LA. During the October-November 1941 Carolina Maneuvers, Patton’s division captured Hugh Drum, commander of the oppos ing army. After the Louisiana Maneuvers, the Army expected to have a period of “re medial training” to fix problems. The Japanese attack on Pearl Harbor Dec. 7, 1941, shattered those expectations and plunged a not-fully-prepared Unit ed States into the war. World War II Following the invasion of Poland and the outbreak of World War II in Europe in 1939, the U. S. military entered ape riod of major mobilization and away-finding among men, machines, train ing, structure and doctrine – for in stance, in the division’s emergence. The Armored Force grew during the course of the war from its initial two to 16 armored divisions. Much of this ex pansion occurred in 1941 and 1942, years in which the Armored Force worked to establish an effective train ing base under Devers and develop op timal organizations for mounted units. The division became the primary focus of this attention. It became the largest American armored formation fielded in World War II, despite early interest in creating an armored corps. The divi sion underwent continuous modification until the establishment of a per manent structure in September 1943. Basic components included three armored battalions, three armored-infantry battalions, three artillery battalions, one engineer battalion, one re connaissance battalion, one medical battalion and one maintenance battalion. The division’s size reflected the Armored Force’s emphasis on organiza tional flexibility and deployability. De liberate efforts were made to keep the formation from becoming too bulky or unmanageable. To facilitate command and control, the new division dis pensed with rigid brigade and regimen tal headquarters. Instead, it relied on subordinate combat commands that possessed a permanent staff but no fixed troop assignments. They were as signed units according to their mission, and their composition changed with the tactical situation or the division commander’s intent. Each combat command in turn organized its assets with up to four task forces, similarly flexible in their structure and operation. Exploitation of the combat-command concept initially suffered from a short age of officers familiar with combined-arms operations and comfortable with the absence of organizational rigidity. Armor-officer training therefore fo cused on fundamentals to ensure a ba sic competency level. Standard com bat-command organizations and solu tions for “typical” tactical situations provided essential guidance, but too often they became rigidly applied in combat theaters. A deeper under standing of combined-arms operations and the utility of the combat-command structure tended to occur only as are sult of combat experience. The Army did not truly possess a combined-arms culture when it entered the war, but it recognized the importance of com bined-arms action by war’send. The division’s rite of passage came when, in August 1942, LTG Dwight D. Eisenhower was named commander-in-chief Allied Force Headquarters to lead the Operation Torch landings – planned for late Fall – and 1st and 2nd Armored Divisions were assigned to the operation. Increased pressure was on Devers to push more armored units through the pipeline even faster. De spite obstacles such as lack of person nel trained in critical military occupa tional specialties and a persistent shortage of tank engines, the Armored Force chief succeeded in getting divi sions and battalions to their ports of embarkation on time, and American and British forces went ashore at Cas ablanca, Oran and Algiers Nov. 8, 1942, as Operation Torch was launched. Training shortfalls also showed up as the Armored Force’s focus on develop ing and fielding armored divisions re sulted in less attention devoted to the separate tank battalions intended for infantry support. These armored units were not permanently assigned to infantry formations and had few oppor tunities to train with riflemen. Many tank battalions were broken into com pany teams and assigned to support different infantry units. Tank-infantry coordination thus became a battalion and company commander’s problem, made worse by the early lack of doc trine for the operation of tanks in ur ban and complex terrain. In the Normandy hedgerows, for example, the close terrain reduced engagement ranges and forced the employment of tanks in small groups rarely larger than a company and more often a platoon’s or section’s size. Mechanized cavalry served in large numbers in World War II, but their nature and composition differed from the general-purpose organization represented by the interwar 7th Cavalry Brigade (Mechanized). Instead, mechanized-cavalry groups and squadrons provided reconnaissance at the corps and division levels. These units were optimized for stealthy reconnaissance and lacked combat power. These characteristics reflected their Cavalry alignment. The Armored Force assumed responsibility for mounted-maneuver combat actions, leaving reconnaissance as the primary function for mechanized-cavalry units. Unfortunately, once deployed, mechanized-cavalry units were often thrust into a much broader range of missions, requiring considerable improvisation. Mechanized-cavalry units included a collection of armored cars, light tanks, jeeps and half-tracks. These platforms generally proved weak in armor protection and anti-tank capability, although they performed effectively against non-tank targets. Despite their light nature, mechanized-cavalry organizations proved versatile and served in every major campaign from the Normandy landings to the conquest of Germany. The United States, however, entered World War II with some faulty philosophy. The defense establishment believed that conventional tanks which could take on enemy Panthers and Tigers toe to toe wouldn’t have the speed and mobility to avoid being flanked and bypassed, and therefore would not have the chance to fight. U. S. defense planners also calculated U. S. interests would be better served by large numbers of “battleworthy” (reliable) medium tanks rather than a smaller number of “unreliable” heavy tanks. As mentioned, production of heavy-tank designs such as the M26 Pershing therefore slowed, and re sources were concentrated on mass-producing the M4 Sherman and TDs such as the M18 Hellcat. (See preced ing section on the dust-up between Devers and McNair.) Since the Sherman medium tank would be inferior to enemy heavy tanks, they would have to avoid tank-vs.-tank combat as much as possible, leaving enemy tanks to the TDs. In actual combat, however, the Germans were unable and unwilling to fight in the fast, free-flowing manner to which the U. S. forces were tuned to counter. Against the defensive and am bush tactics the Germans actually used, McNair’s doctrine led to U. S. tanks having weaker guns and less armor protection than their German counterparts, and in the narrow con fines of much of the terrain in Norman dy, they could not avoid one-on-one encounters with German tanks. Fortunately Patton, for one, knew how to fight his tanks as the United States fielded them. Patton’s strategy with his army favored speed and aggressive offensive action. Patton’s Third Army typ ically employed forward scout units to determine enemy strength and positions. Self-propelled artillery moved with the spearhead units and was sited well forward. Light aircraft such as the Piper L-4 Cub served as artillery spot ters and provided airborne reconnais sance. Once the enemy was located, the armored infantry would attack, us ing tanks as infantry support. Other ar mored units would then break through enemy lines and exploit any subse quent breach, constantly pressuring withdrawing German forces to prevent them from regrouping and reforming a cohesive defensive line. U. S. armor ad vanced using reconnaissance by fire, and the.50 caliber M2 Browning heavy machinegun proved effective in this duty, often flushing out and killing German panzerfaust teams waiting in am bush as well as breaking up German in fantry assaults against the armored in fantry. An example of the success of Patton’s strategy was the fighting around Arra court in September 1944. The battle was part of the Lorraine Campaign, in which the German LVIII Panzer Corps mounted a series of counterattacks to stem the avalanche of Allied troops that had poured across France follow ing their breakout from the Normandy beachhead. The principal fighting in volved elements of 4th Armored Division led by LTC Creighton Abrams. The flexible organization and combined-arms nature of this formation permit ted it to attach and detach units as necessary to meet enemy threats. This flexibility allowed U. S. forces to employ combined-arms teams to outma neuver and outfight German forces equipped with superior tanks whose frontal armor could not be penetrated easily by American tank guns. The 4th Armored Division shifted forces as much as eight to 10 kilometers to meet German probes. American forces also launched local attacks wherever pos sible against flanks and weak points, thereby retaining the element of sur prise. The battle concluded with the repulse of the German attack and the destruction of two entire panzer bri gades at a cost in materiel of only 21 American tanks. When the war ended, armored organi zations had demonstrated their value in every theater in which American forces fought. The armored division constituted a powerful, mobile com bined-arms mix. Its organizational flexibility, combat power, high operational tempo and command arrangement en sured it a place in the postwar Army. The tank was considered the optimum anti-tank system, and its versatility led to the abolition of specialized TD units and the emergence of the main battle tank (MBT) concept. Conversely, the mechanized-cavalry experience re vealed a universal desire for more ef fective reconnaissance organizations and equipment that would ultimately result in the creation of the armored-cavalry regiment and more robust divi sional Cavalry squadrons. Post-World War II: 1950s-1960s The years immediately after World War II were marked by efforts to analyze the wartime experience and Figure 5. M4 Shermans at the Battle of Arracourt. (U. S. Army Signal Corps pho to) incorporate lessons-learned into mounted maneuver training, organization, materiel and doctrine. In 1946, Fort Knox hosted the first annual con ference dedicated to Armor issues. Future development, however, hinged on the creation of a permanent Armor Branch. The Armored Force had been created by the Army leadership in World War II as a “service test” to per mit the rapid creation of the mechanized forces considered necessary for the war effort, but the organization lacked the legal foundation of the other combat arms. Hence, Army leaders now focused upon the creation of a permanent branch, its impact and whether it would include the Cavalry. The Army Organization Act resolved the branch question in 1950. Under this legislation, a single Armor Branch emerged to govern both tank and cav alry development. A separate Cavalry Branch ceased to exist. A single command now bore responsibility for the development of armored formations, separate tank battalions and cavalry units. The branch’s birthdate became Dec. 12, 1776, to reflect its combined Cavalry and Armor heritage. The years following the end of World War II provided a different type of challenge for mounted-maneuver or ganizations. In Europe, the Army found itself responsible for governing a large section of Germany and Austria. The war-induced chaos in these areas, coupled with a potentially hostile popula tion, generated the need for a means of providing security and maintaining order. To assist in these tasks, the Army created the Constabulary in July 1946. The creation of a Constabulary School modeled on the Armored School at Fort Knox helped immerse Soldiers in German language, culture and the le gal responsibilities associated with their duties. By 1948 a reorganized German police force began to assume many of the functions the Constabulary initially conducted. The onset of the Cold War and the growing threat of Soviet aggression triggered a change in the Constabulary’s mission and organization. A num ber of Constabulary units were restruc tured to form the Army’s first armored-cavalry regiments. The Constabulary continued to support major law-enforcement activities, but it also began to increase its combat capability through the acquisition of medium tanks and increased tactical training. These changes reflected a growing de sire for more combat power in Germany to protect Central Europe from Soviet aggression. Adapted from U. S. Army Armor School Pamphlet 360-2, This is Armor, and other sources. Next edition: Part 2 of the Armored Force history. Further reference U. S. Army Armor School Pamphlet 360-2, This is Armor. Armor Museum Director Len Dyer dis cusses tank development in “Tank Talk” on Fort Benning TV, https://www.you tube.com/watch?v=tSXR72MUruM. The Sheridan tank dedication on Eubanks Field July 10, 2015 is featured at https:// www.youtube.com/watch?v=kZf3L_5pXfI. More historical articles can be found in the “Armor” section of eARMOR’s heri tage page, http://www.benning.army.mil/ armor/eARMOR/Heritage.html. Notes 1 Chaffee was called the “Father of the Armored Force” for his role in developing the Army’s tank forces. Commissioned a lieutenant of Cavalry in 1906 after gradu ating from the US. Military Academy, he won recognition as the “Army’s finest horseman.” The M24 Chaffee light tank was later named after him. He died Aug. 22, 1941, of cancer in Boston. Chaffee’s associates admired his persistence in the face of a lack of organizational and finan cial support he and other tank-warfare enthusiasts received in the 1930s. Especially see retired MG Robert W. Grow, The Ten Lean Years: from the Mechanized Force (1930) to the Armored Force (1940). Manuscript in Patton Museum Collection, Fort Knox, KY. For a descrip tion of Chaffee, see Mildred Gillie, Forging the Thunderbolt (Harrisburg, PA, The Military Service Publishing Company, 1947). Gillie worked with the now-missing Chaffee Papers. 2 COL Bruce Palmer, “Mechanized Cavalry in the Second Army Maneuvers,” Cavalry Journal, November-December 1936. 3 Gillie. 4 Ibid. 5 Patton is perhaps best known for his leadership of Third U. S. Army in France and Germany following the Allied invasion of Normandy in 1944. Patton led Third Army in a highly successful, rapid ar mored drive across France. He led the re lief of beleaguered U. S. troops at Bas togne during the Battle of the Bulge and advanced his army into Nazi Germany by the end of the war. Patton was commissioned a second lieutenant in the Cavalry June 11, 1909. 6 The M26 Pershing was the culmination of a series of tank prototypes that began with the T20 in 1942. The M26 was a sig nificant design departure from the previ ous line of U. S. Army tanks that had end ed with the M4 Sherman. A number of design features were tested in the various prototypes, some of which were experimental dead ends, but many design fea tures became permanent characteristics of modern U. S. Army tanks. The proto type series began as a medium-tank up grade of the M4 Sherman and ended as the U. S. Army’s first operational heavy tank, according to R. P. Hunnicutt in his book Pershing, A History of the Medium Tank T20 Series (Feist Publications, 1996). After the initial prototypes were built in early 1943, an additional 250 T23 tanks were produced from May-December

1943. These were the first tanks in the U. S. Army with the 76mm M1A1 gun to go into production, according to Hun nicutt. However, the T23 would have re quired that the Army adopt an entirely separate line of training, repair and maintenance, and so was rejected for combat operations. The T25 and T26 lines of tanks came into being in the midst of the U. S. Army’s heated internal debate in mid-1943 to early 1944 over the need for tanks with greater firepower and armor. A 90mm gun mounted in a massive new tur ret was installed in both series. The T26 series was given more frontal hull armor, with the glacis plate increased to four inches (10 centimeters). This increased the weight of the T26 series to more than 40 short tons (36 tonnes) and decreased its mobility and durability, as the engine and powertrain were not improved to compensate for the weight gain. Chrysler built a single prototype of a T26 turret mounted on an M4A3 chassis in Summer 1944 but did not progress into production. See also George Forty, United States Tanks of World War II (Blandford Press, 1983). According to Forty, the Ordnance Department recommended that 1,500 of the T26E1 be built. The Armored Force recommended only 500. Although the AGF rejected the tank’s 90mm version and wanted it to be built with the 76mm gun instead, somehow Ordnance man aged to get production of the T26E1 start ed in November 1944.

27 7 Steven J. Zaloga, Armored Thunderbolt, Stackpole Books, 2008. 8 In addition to infantry, artillery and close air support, the U. S. combined-arms team included engineers, and the tank compo nent was supplemented by the TD con cept. McNair is most closely identified with proponency of TDs/anti-tank weap ons. Having studied early German suc cesses, McNair had come to believe U. S. forces would be faced with fast-moving enemy forces who would seek to bypass, isolate and reduce U. S. forces in a replay of the Fall of France. To counter the ene my blitzkrieg, McNair sought to improve the organic anti-tank strength of U. S. infantry divisions by attaching towed antitank guns and equipping the infantry with hand-held bazookas. To stem the flood of marauding panzers, fast-moving, power fully armed TD battalions were created to be held back and used in the counterattack. Acronym Quick-Scan AC – Active Component ACAV – Armored Cavalry Assault Vehicle ACR – armored Cavalry regiment AGF – Army Ground Forces AGS – Armored Gun System ARNG – Army National Guard BCT – brigade combat team BMP – boyeva mashina pekhoty CFV – Cavalry Fighting Vehicle COIN – counterinsurgency FBCB2 – Force XXI Battle Command Brigade and Below FCS – Future Combat System GHQ – General Headquarters IED – improvised explosive device MBT – main battle tank MCoE – Maneuver Center of Excellence MGS – Mobile Gun System NATO – North Atlantic Treaty Organization NTC – National Training Center RC – Reserve Component RPG – rocket-propelled grenade RSTA – reconnaissance, surveillance and target acquisition SAM – surface-to-air SBCT – Stryker brigade combat team TD – tank destroyer TO&E – table of organization and equipment TOW – tube-launched, optically tracked, wire-guided Armored Force key dates Jan. 26, 1918 U. S. Tank Corps established 1920

National Defense Act of 1920 abolishes Tank Corps and assigns responsibility for tank development to Infantry Branch 1928

Experimental Mechanized Force established at Fort

George G. Meade, MD 1930

Mechanized Force created at Fort Eustis, VA 1931

Army implements new mechanization policy that permits Cavalry development of a mechanized component 1931

Mechanized Force disbanded; remnant element renamed Detachment for Mechanized Cavalry and Camp

Knox, KY, becomes home of mechanized cavalry 1933

1st Cavalry Regiment (Mechanized) arrives at Fort Knox July 10, 1940 Army authorizes creation of the Armored Force at Fort

Knox as a “service test” to centralize mechanized development 1942

Office Chief of Cavalry abolished 1943

Armored Force redesignated Armored Command 1944

Armored Command redesignated as Armored Center 1945

Armored Center inactivated 1946

Armored Center reactivated 1948

Organization of the first armored-cavalry regiments June 28, 1950 Army Organization Act establishes Armor as separate branch of Army 1972

MBT task force established at Fort Knox to develop requirements for new tank, which becomes the Abrams tank 1973

Arab-Israeli October War triggers changes in Army doctrine and increased emphasis on platforms capable of fighting on highly mechanized battlefield 1980

Fielding of M1 Abrams tank begins 1981

Fielding of M2/M3 Bradley Fighting Vehicle begins 1990

Army authorizes fielding of humvee to all maneuverbattalion scout platoons 1992

First light ACR created when 199th Separate Motorized

Infantry Brigade is reflagged as 2nd ACR 1994

Desert Hammer VI becomes first test of prototype armored brigade at NTC 1995

Fort Knox hosts advanced warfighting experiment Focused Dispatch, which demonstrates ability to integrate virtual and live training 1999-2000

Fort Knox hosts platform-performance demonstration to assess available vehicles for use in new medium brigade, later designated the Stryker BCT 2003

Modularity initiative restructures Army around BCTs as principal maneuver elements Oct. 1, 2013

MCoE reorganizes into the university design with training brigades focused and aligned specifically for initial military training and functional training Adapted from U. S. Army Armor School Pamphlet 360-2, This is Armor.