Prior to the start of the Cold War, propaganda was spread in 1942, persuading U.S. citizens that they are our allies, as we all have the same goals as well as they supported us moving in on Japan.

Since this was during the time of World War 2, mistrust was present between both nations. The past actions that the U.S. has shown when they were allies were not the best, as they joined the war late as well as ignore their allies in need of help due to not wanting to get involved.

Although both the nations remained victorious against the Japanese, this did not ensure them being allies. Both nations had colliding ideologies for their governments, communism and democracy. 

The U.S. and USSR competed, as they tried to gain alliances with other smaller nation as they provided aid towards them in order to not just gain alliances with them, but also spread either communism or democracy.

Proxy wars were fought between the two rival's allies (smaller nations that they supported), especially as the war went on. Germany was split into four occupation zones. Churchill believe there was an iron curtain diving Germany.

In fear of communism spreading, the U.S. followed a containment policy to prevent it. They believed that if they lost Greece to the USSR, a domino effect will unfold, leading to the immense spread of communism. Truman Doctrine said we need to financially aid growing nations in order for them to adopt our form of government.

People opposed the Truman Doctrine, such as Henry Wallace as he proposed his views on it. He explains that it will not be successful because there's inevitable change in the World that money can't fix, as well as we can't just buy other nations by lending them billions of dollars. Instead he said the U.S. should send material resources to help.

The Marshall plan was adopted (not going against any policy or doctrine), but just remain humane and help those who are starving or are in poverty, giving European nations hope. Novikov (soviet leader) opposed this plan as he believe the U.S. is trying to grow in power, using the widespread U.S. military bases as an example.