The USSR (Soviet Union) was predominantly communist, with a totalitarian government (basically, there was no democracy; it was a dictatorship). While, on the other hand, the USA (United States) remained as a capitalist country with a democratic government.
The Soviet Union was controlled/manipulated by local communist parties and by a Supreme Soviet. On the opposite side of the spectrum, the United States was governed by two political parties (Republican/Conservative and Democratic/Liberal).
EDIT: If you need more information, let me know.
