The United States and the Soviet Union were never confronted in a direct military conflict, never confronted in a "Hot War". After World War II, the two countries started a "cold war" because the rivalry between the two superpowers originated in the incompatibility between the ideologies defended by each side. This ideological incompatibility could be perceived in the fact that each superpower had a different political system and organized its economy differently from the other. While the United States defended capitalism, democracy, principles such as the defense of private property and free enterprise, the Soviet Union defended socialism and principles as the end of great private property, economic equality (a society without rich and poor ) and a strong State able to guarantee the basic needs of all citizens.
No. there really isn't an excuse to why anybody isn't treated or seen as an equal. Everybody is and should be treated an equal. In back then, if you're going to create equality and speak equality you should probably practice what you preach.