Why did the USA-USSR alliance begin to break down in 1945?

The alliance between the USA and the USSR began to break down in 1945 due to distrust.

Reasons for Distrust

1) Different Political Systems

Communism:

Soviet Union has been communist since 1917. Communists base their beliefs on the writing of Karl Marx. He believed that:

-The government should control all aspects of citizens' lives

-Individual rights less important than what was good for the country as a whole.

-Industry and agriculture should be owned by the state and profits made should be used for the common good.

So in the Soviet Union:

-There were no wealthy businessmen using their capital to take risks and make personal fortunes.

-No private profit.

-No political freedom. There was only one party, a communist one.

-No freedom of speech.

-Government controlled newpapers, tv and other media.

Capitalism:

The USA was a capitalist country, so:

-Industry and agriculture…