This fear was not unfounded, as Soviet leaders actively sought to infiltrate or target nations to advance the global influence of the USSR. Ever since the Bolshevik Revolution in 1917, in which the Russian monarchy fell to Soviet forces, the spread of communism beyond Russia remained a persistent fear throughout the twentieth century.

While President Roosevelt hoped to see a lasting peace emerge in the postwar world order, relations with the Soviet Union complicated that vision.

The subsequent race for superior military power sparked an era of espionage, wars over the spread of communism, and a build-up of nuclear arms that threatened global annihilation. Following the defeat of the Axis powers, an ideological and political rivalry between the United States and the USSR gave way to the start of the Cold War. As World War II transformed both the United States and the USSR, turning the nations into formidable world powers, competition between the two increased. However, Germany’s invasion of the Soviet Union and Japan’s attack on Pearl Harbor created an alliance between the United States and the USSR. Western Allied leaders did not forget the initial nonaggression pact made between Soviet Premier Joseph Stalin and Adolf Hitler in 1939. Tensions between the United States and its unlikely ally in the Soviet Union persisted throughout World War II. Top image courtesy of the National Archives and Records Administration, 198923.

Why was it called the cold war