Changes

Following the Nazi defeat of France in June of 1940, Roosevelt grew wary of the increasing aggression of the Germans and made some diplomatic moves to improve relations with the Soviets. Beginning in July of 1940, a series of negotiations took place in Washington between Under-Secretary of State Sumner Welles and Soviet Ambassador Constantine Oumansky. Welles refused to accede to Soviet demands that the United States recognize the changed borders of the Soviet Union after the Soviet seizure of territory in Finland, Poland, and Romania and the reincorporation of the Baltic Republics in August 1940, but the U.S. Government did lift the embargo in January 1941.

The most important factor in swaying the Soviets eventually to enter into an alliance with the United States was the Nazi decision to launch its invasion of the Soviet Union in June 1941. President Roosevelt responded by dispatching his trusted aide Harry Lloyd Hopkins to Moscow in order to assess the Soviet military situation. Although the War Department had warned the President that the Soviets would not last more than six weeks, after two one-on-one meetings with Soviet Premier Josef Stalin, Hopkins urged Roosevelt to assist the Soviets. By the end of October, the first Lend-Lease aid to the Soviet Union was on its way. The United States entered the war as a belligerent in late 1941 and thus began coordinating directly with the Soviets, and the British, as allies.