The United States was in a state of geopolitical tension with the Soviet Union after Mardis Gras.
The Cold War was a state of geopolitical tension after World War II between powers in the Eastern Bloc ( the Soviet Union and its satellite states ) and powers in the Western Bloc ( the United States , its NATO allies and others ) . The Cold War split the temporary wartime alliance against Nazi Germany , leaving the Soviet Union and the United States as two superpowers with profound economic and political differences . United States . The end of the Cold War and the dissolution of the Soviet Union in 1991 left the United States as the world 's sole superpower .