During World War II, the United States began to provide significant military supplies and other assistance to the Allies in September 1940, even though the United States did not enter the war until December 1941. Much of this aid flowed to the United Kingdom and other nations already at war with Germany and Japan through an innovative program known as Lend-Lease.
Though President Roosevelt wanted to provide assistance to the British, both American law and public fears that the United States would be drawn into the conflict blocked his plans. The Neutrality Act of 1939 allowed belligerents to purchase war materiel from the United States, but only on a "cash and carry" basis. The Johnson Act of 1934 also prohibited the extension of credit to countries that had not repaid U.S. loans made to them during World War I--which included Great Britain. The American military opposed the diversion of military supplies to the United Kingdom. The Army's Chief of Staff, General George C. Marshall, anticipated that Britain would surrender following the collapse of France, and thus American supplies sent to the British would fall into German hands. Marshall and others therefore argued that U.S. national security would be better served by reserving military supplies for the defense of the Western Hemisphere. American public opinion also limited Roosevelt's options. Many Americans opposed involving the United States in another war. Even though American public opinion generally supported the British rather than the Germans, President Roosevelt had to develop an initiative that was consistent with the legal prohibition against the granting of credit, satisfactory to military leadership, and acceptable to an American public that generally resisted involving the United States in the European conflict.
In December 1940, Churchill warned Roosevelt that the British were no longer able to pay for supplies. On December 17, President Roosevelt proposed a new initiative that would be known as Lend-Lease. The United States would provide Great Britain with the supplies it needed to fight Germany, but would not insist upon being paid immediately
Instead, the United States would "lend" the supplies to the British, deferring payment. When payment eventually did take place, the emphasis would not be on payment in dollars. The tensions and instability engendered by inter-allied war debts in the 1920s and 1930s had demonstrated that it was unreasonable to expect that virtually bankrupt European nations would be able to pay for every item they had purchased from the United States. Instead, payment would primarily take the form of a "consideration" granted by Britain to the United States. After many months of negotiation, the United States and Britain agreed, in Article VII of the Lend-Lease agreement they signed, that this consideration would primarily consist of joint action directed towards the creation of a liberalized international economic order in the postwar world.