U.S.A's role in the Cold War/ modern day analysis

Americas role in the Cold War was to keep communism from spreading to other parts of the world and to prevent the USSR from starting a nuclear war. They used defencive tactics and political influences to make sure no nuclear war would destroy the world. Americas role can still be seen now in the politacal decisions that Russa and America are makeing. For example President Obama and the Russian President signed a treaty that lowered the number of nuclear weapns and launchers each country can have at one time.