A what if...what if the communists had won and actually linked up with the Soviet Union? That was just about the choice Germany had at the time.
In our current situation in the US I am on the side of whoever is the most brutal, merciless and relentless in destroying antifa, BLM etc.
Socialism from the right or socialism from the left is still socialism. The choice you described had nothing to do with ideology. It was just two socialist dictators fighting for more power. It's laughable, one claiming the power in the name of the state and one in the name of the people.