The year 1941 was one of extreme changes in the United States, as World War II entered more and more Americans' thoughts and touched American lives. The North African campaign became more intense, with Germany's Afrika Korps arriving in Tripoli and retaking land lost in late 1940. German U-boats continued to disrupt the shipping lanes between the United States and Great Britain.

On May 27, however, the Germany battleship Bismarck was sunk on its way home from sinking the British battle cruiser Hood off Greenland. That loss hurt Germany's naval power. U.S. involvement continued to grow, although the neutrality law prohibited U.S. vessels and nationals from traveling in combat zones. In March 1941 Congress passed the Lend-Lease Act, allowing the president to authorize shipment of vital war materiel to nations, primarily Great Britain, whose defense he considered to be necessary for U.S. security. In August and September, U.S.-owned ships were sunk, which led to legislation authorizing the arming of U.S. merchant vessels and permitting them to carry cargoes to belligerent ports.

The Atlantic Charter was conceived August 14, 1941, on a war vessel off the coast of Newfoundland, to be endorsed the following month by the United States, Great Britain, USSR, and 14 other anti-Axis countries. On December 7, the Japanese bombed Pearl Harbor, provoking a declaration of war against the island nation, and four days later Germany and Italy declared war against the United States.