Lend-Lease Act

The Lend-Lease policy, formally titled "An Act to Promote the Defense of the United States", (Pub.L. 77–11, H.R. 1776, 55 Stat. 31, enacted March 11, 1941) was a program under which the United States supplied Free France, the United Kingdom, the Republic of China, and later the Soviet Union and other Allied nations with food, oil, and materiel between 1941 and August 1945. This included warships and warplanes, along with other weaponry. It was signed into law on March 11, 1941 and ended in September 1945. In general the aid was free, although some hardware (such as ships) were returned after the war. In return, the U.S. was given leases on army and naval bases in Allied territory during the war. Canada operated a similar smaller program under a different name.

A total of $50.1 billion (equivalent to $667 billion today) worth of supplies was shipped, or 17% of the total war expenditures of the U.S. In all, $31.4 billion (equivalent to $418 billion today) went to Britain, $11.3 billion (equivalent to $150 billion today) to the Soviet Union, $3.2 billion (equivalent to $42.6 billion today) to France, $1.6 billion (equivalent to $21.3 billion today) to China, and the remaining $2.6 billion to the other Allies. Reverse Lend-Lease policies comprised services such as rent on air bases that went to the U.S., and totaled $7.8 billion; of this, $6.8 billion came from the British and the Commonwealth. The terms of the agreement provided that the materiel was to be used until returned or destroyed. In practice very little equipment was returned. Supplies that arrived after the termination date were sold to Britain at a large discount for £1.075 billion, using long-term loans from the United States. Canada operated a similar program called Mutual Aid that sent a loan of $1 billion and $3.4 billion in supplies and services to Britain and other Allies.

This program effectively ended the United States' pretense of neutrality and was a decisive step away from non-interventionist policy, which had dominated United States foreign relations since 1931. (See Neutrality Acts of 1930s.)

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