How the Cold War ideology that crystallized after WWII changed wartime alliances that had existed during the war. I understand how there was a nuclear threat between the US and Russia. The confusion are the other alliances we had during the war. Did we anger other countries due to winning the war? What if anything caused our friendship to change and with whom?
The Allies predominantly consisted of Great Britain (and the commonwealth countries like Australia, Canada, etc.), the USA, France (which wasn't able to do too much because of the German occupation) and the USSR. This was a very bizarre alliance. Why would the USA and Great Britain ally themselves with the Soviet Union, one of the worst dictatorial, freedom-hating, murderous regimes ever on the planet? Remember, Joseph Stalin was more of a butcher of his own people than was Adolf Hitler! Doesn't that seem like an odd alliance?
On the other side, the Axis, were Germany, Italy, and Japan (mostly, although there were other minor players).
What happened to these alliances? Near the end of the war in Europe, Mussolini was captured and overthrown. He was executed and the Italians switched sides (similar to what they did near the beginning of WWI) and joined the Allies. (They knew which side was going to win!) So, the Italians went from being enemies to being friends of the Allies. They joined the Americans in fighting against the Germans.
What about Japan? After the defeat of the Japanese Empire, the US government installed a military occupation with General Douglas MacArthur as head of the ...