Camp Colt to Desert Storm: The History of U.S. Armored Forces

8. The Marine Corps's Struggle with Armor Doctrine during the Cold War (1945-70)

8 The Marine Corps's Struggle with Armor Doctrine during the Cold War (1945-70) Kenneth W. Estes The Japanese surrender announcement found most of the Marine Corps, then some 458,000 strong, deployed in the western Pacific with the I, III and V Amphibious Corps, their six divisions and four aircraft wings in the Fleet Marine Force, Pacific (FMFPAC). Apart from demobilization concerns, their duties consisted of disarming Japanese forces and occupying parts of Japan and China. Postwar planning centered on a ready force of two divisions and two aircraft wings, plus corps troops, balanced between the Marine Corps's East and West Coast bases, for duty primarily with the Atlantic and Pacific Fleets. Marines quickly terminated their occupation duties in Japan, but deployments in China dragged on into early 1947. Nevertheless, by the end of 1946, barely fifteen thousand Marines remained on FMFPACs rolls, and an even smaller number in the fledgling Fleet Marine Force, Atlantic (FMFLANT).1 The Pacific War saw the refinement of amphibious doctrine and the expansion of the FMF far beyond the scope imagined by the planners and dreamers of the interwar period. The amphibious tractor (amtrac) became the staple of the amphibious assault force, spearheaded by its howitzer-armed and better-armored cousin, the armored amphibian . By mid-1945, three armored amphibian battalions and nine amphibian tractor battalions stood ready for the final assaults on Japan. The 264 Kenneth W. Estes demobilization left only a skeletal battalion with one amtrac company and an LVT(A) platoon in each division, but the 10th, 11th, and 12th Amtrac Battalions, each with an armored amphibian company included, were retained on paper with the Marine Corps Reserve. More than eighteen thousand amtracs were produced during the war, but efforts to recover them from the western Pacific proved limited . Most were obsolete or worn out, and were left in Marianas or Hawaiian staging bases. Some three hundred LVTs were shipped from Guam to the depot at Barstow, California. Several hundred more made their way to the desert depot from Oahu. Most of the recovered vehicles were of the latest LVT3 and LVT(A)5 types, and by 1948 fifteen hundred amtracs had been mothballed at Barstow in various states of condition.2 Tank units in the Marine Corps had endured rapid changes during the war in terms of both equipment and tactical employment. The light tank generally failed in the infantry support role so often demanded of it, and the light tank battalions and mixed battalions eventually gave way to medium battalions, six of which stood ready in their parent Marine divisions for the final battles in 1945. The tank-infantry tactics that evolved from the Pacific island battles stressed close support of squads of riflemen by individual tanks, and vice versa. Tank platoons thus were organized with four tanks. By war's end, the flame tank platoons made up of three vehicles had been moved from the battalion structure and one was assigned to each line company, reflecting its essential part in the tactical array. The Shermans had proven unstoppable to all but the most desperate Japanese countermeasures and were widely credited by the Imperial Army with unhinging Japanese defenses. Although tied to the infantry support role, the tankers in the Corps still relished the opportunity to employ mobility and mass and did so on Roi-Namur, Guam, Okinawa, and in a massive attack on Iwo Jima's airfield by three battalions.3 Unlike the development and production of the amtracs, performed for the Marine Corps by the Navy's Bureau of Ships, the Corps came to depend exclusively upon the Army for the procurement of tanks. Army production schedules and logistics support policies began to dictate Marine Corps tank equipment decisions as early as 1944. The cherished twin-diesel M4A2 Shermans had to be replaced by gas-powered M4A3s rapidly, before the production line changed to the undesirable 76mm guns, simply to remain within Army logistics support and design configuration policies. Later, the Marine tank fleet was reequiped with M4A3E8s equipped with 105mm howitzers when the Army shifted to production of the M26 Pershing, keeping only the 105mm Sherman line open. Curiously, the advent of the M24 caused the Corps to again con- Armor Doctrine during the Cold War 265 sider the employment of light tanks. Ten M24s were procured in 1945 for testing with a fording kit at Camp Pendleton. They remained in...