The Lend-Lease Act, enacted in 1941, was significant in World War II as it enabled the U.S. to provide military aid to its allies, particularly Britain and later the Soviet Union. This program allowed for the transfer of supplies, equipment, and war materials without immediate payment, bolstering the Allied powers against Axis aggression. The act symbolized a shift in U.S. foreign policy from isolationism to active involvement in global affairs. Lend-Lease played a crucial role in sustaining Allied forces, significantly contributing to their eventual success and marking a pivotal moment in the understanding of international support in warfare.