American military technology during World War II US cruisers and battleships had their guns directed using information gathered from the ship's radar. 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,
World War II had been used predominantly for infantry support in the First World War, had evolved into the primary weapon. In the late 1930s, tank design was considerably more advanced than it had been during World War I, and advances continued throughout the war with increases in speed, armour and firepower. At the start of the war, most commanders thought enemy tanks should be met by tanks with superior specifications. This idea was challenged by the poor performance of the relatively light early tank guns against armour, and German doctrine of avoiding tank-versus-tank combat. This, along with Germany's use of combined arms,