Germany proved the effectiveness of tanks in combat during the invasion of France and held superiority in this area throughout much of the war. For a variety of reasons, the United States was slow to produce a heavy tank that equaled the German Panther or Tiger, though heavy Allied tanks did appear late in the war.

When German tanks crossed the border into France in 1940, the United States had just 464 tanks, most of them light tanks armed with .50-caliber machine guns. By comparison, the German Pzkw IV tank was armed with a 75-mm gun.

Figure 10-2 A tank moves forward on the island of Bougainville with infantry following in its cover.

Photo courtesy of the National Archives (111-SC-189099)

In July 1940, the U.S. War Department — inspired by the tremendous success of German armored units — created an armored force consisting of the First and Second Armored Divisions and the nondivisional Seventieth Tank Battalion.

Realizing the need for a heavier, better-armed tank, the army's Ordnance Department adapted the TS medium tank to carry a 75-mm gun on the right side, though the main turret still had a 37-mm gun. The new tank, called the M2 Grant, was widely used to great effectiveness by the British in North Africa.

Following was the M4 Sherman tank, the first to be armed with a primary 75-mm gun. It went into production in July 1942 and was widely used by U.S. Army and Marine Corps forces in the Atlantic, Pacific, and North African theaters. The Sherman was also used by the British and Free French forces.

As strong as the Sherman tank was, it was still no match for the German Panther and Tiger tanks, both of which carried larger guns. The Ordnance Department was eager to place a 76-mm long-barreled gun on the Sherman, but the plan was continually hampered by army officials who instead stressed the need for faster light tanks that could keep up with fast-moving infantry. Finally, in February 1944, the Ordnance Department was instructed to begin adding a 76-mm gun to the Sherman chassis. These hybrids were produced in small numbers but proved effective against opposing forces. A still stronger tank — the M26 Pershing, which featured an impressive 90-mm gun — followed; it was the heaviest tank mass-produced by the U.S. military.

Because of the widespread use of tanks in Europe, special tank destroyers — tank-type vehicles with open turret tops and thin side armor — were quickly put into action. By late 1942, the U.S. Army had thirty-six tank destroyer battalions, each with thirty-six guns, in addition to reconnaissance and antiaircraft weapons. Approximately half the tank destroyer battalions towed antitank guns. The other half had self-propelled tank-destroying vehicles such as the M10 Wolverine and the M18 Hellcat, both of which featured a 76-mm gun, and the M36, which boasted a 90-mm gun.