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
Nazi crimes against the Polish nation Nazi crimes against the Polish nation Crimes against the Polish nation committed by Nazi Germany and collaborationist forces during the invasion of Poland, along with auxiliary battalions during the subsequent occupation of Poland in World War II, consisted of the systematic extermination of Jewish Poles and the murder of millions of (non-Jewish) ethnic Poles. The Germans justified these genocides on the basis of Nazi racial theory, which depicted Jews as a constant threat and regarded Poles and other Slavs as racially inferior "Untermenschen". By 1942 the Nazis were implementing their plan to kill every Jew in German-occupied Europe, and had