Military history of the United States during World War II Military history of the United States during World War II The military history of the United States in World War II covers the war against Germany, Italy, and Japan, starting with the 7 December 1941 attack on Pearl Harbor. During the first two years of World War II, the United States had maintained formal neutrality as made official in the Quarantine Speech delivered by U.S. President Franklin D. Roosevelt in 1937, while supplying Britain, the Soviet Union, and China with war materiel through the Lend-Lease Act which was signed into law on 11 March 1941, as well as deploying the
Resistance during World War II first years of the war (1941–1942), but grew rapidly in the latter years, outnumbering the Polish and Soviet partisans by 2:1 or more (estimates give Yugoslavian forces about 800,000 in 1945, to Polish and Soviet forces of 400,000 in 1944). Some authors also call it the largest resistance movement in Nazi-occupied Europe, for example, Kathleen Malley-Morrison wrote: "The Yugoslav partisan guerrilla campaign, which developed into the largest resistance army in occupied Western and Central Europe...". The numbers of French resistance were smaller, around 10,000 in 1942, and swelling to 200,000 by 1944. Resistance during World War II Resistance movements during