At the outbreak of World War II in Europe, the United States initially remained neutral and did not get directly involved in the conflict. However, President Franklin D. Roosevelt implemented measures to support the Allies, such as the Lend-Lease Act which allowed the US to provide military aid to countries fighting against the Axis powers. The US also began increasing its military preparedness and gradually shifted towards a policy of providing more overt support to the Allies as the war progressed. Ultimately, the US entered World War II in December 1941 following the Japanese attack on Pearl Harbor.
