American military technology during World War II American military technology during World War II American military technologies developed during World War II became more advanced and specialized as the war progressed. The technologies produced ranged in complexity from relatively simple items such as small arms and armored vehicles, including tanks, to more complex items such as the atomic bomb. The latter, produced under the secretive Manhattan Project, proved to be an incredibly powerful weapon that revolutionized warfare and was used to end the war. Other technologies, such as the M4 Sherman tank, the M1 Garand and M1 Carbine, and the gas mask, were refinements on previously existing
Main battle tank (and the corresponding transport and logistical needs). This led to new definitions of heavy and light tank classes, with medium tanks covering the balance of those between. The German Panzer IV tank, designed before the war as a "heavy" tank for assaulting fixed positions, got redesigned during the war with armour and gun upgrades to allow it to take on anti-tank roles as well, was reclassified as a medium tank. The second half of World War II saw an increased reliance on general-purpose medium tanks, which became the bulk of the tank combat forces. Generally, these designs massed about 25-30