How did hostilities increase between the United States and the Soviet Union during the 1950s?

The 1950s was a period right after WW2. Even though during WW2 both the United States and the Soviet Union fought against the Third Reich, these two countries had a fundamentally different political system and ideology. On one side the United States was a democracy, on the other side the Soviet Union was a communist country. Post WW2 the two main superpowers were these two countries, in international relations this is known as "bipolarity", where there is two main superpowers and their respective allies. The Soviet Union and the United States were categorised into two main blocs, known as the Eastern Bloc and the Western Bloc. Essentially when Germany was split, the Soviet Union controlled the East and other Eastern European countries such as Poland, Romania, Czechoslovakia etc. United States and their allies controlled the western part of Europe. Each of these two superpowers wanted to assert their influence over other countries and reign supreme, NATO was created and likewise the Warsaw Pact. In 1950 the Korean War happened, the United States supported South Korea meanwhile the Soviet Union supported the North. Likewise in the Vietnam War the same scenario unfolded. This is how the hostilities began with these two superpowers, they both wanted to assert their dominance and gain an advantage in geopolitics.