Please remember that Hitler (Nazi/Socialist/Fascist) and Stalin (Communist) had signed a nonaggression pact so Hitler could concentrate on England and the West. They weren’t opposites. When Hitler betrayed his pact with his commie brothers, it was the start of his unraveling. In fact, it was the nonaggression pact Hitler signed with the Russian communists that precipitated all the American-communist (Union/progressive) resistance to get involved in the war against Hitler. The unions deliberately sabotaged the American industrial base until Hitler betrayed Stalin, their benefactor!
The truth hurts.
Of course, Hitler always intended to betray Stalin, and many believe Stalin held the same intentions towards Hitler. The question was always "when" rather than "if". But this was more because of their physical proximity than any philosophical differences. Germany could more easily "ally" with the totalitarian Japanese empire as they were a world away.
It is interesting to speculate what would have happened had Hitler realized that after his Balkan adventures in Spring 1941 that June didn't allow sufficient time to complete his Russian campaign and that it would be better timed for Spring 1942. Had Japan bombed Pearl Harbor in December 1941 while the Germans and Soviets were still "at peace" it's difficult to see how America could have found itself at war with anyone other than Japan.