[Enterprise]

I think that at the time, the choice for them wasn't too difficult. Stalin had starved 7 million Ukrainians to death in the winter of 1932/1933. They knew about the gulags and the general terror of the secret police. The Nazis were willing to fight Russia, so for a country which had already suffered the deaths of MILLIONS of its citizens to communism, the choice for the Ukrainians seemed obvious.

We understand in retrospect what a terrible choice they had.

[Trapped Behind Enemy Lines]

Yes and three biggest mistakes Hitler made when he invaded the USSR were:

1) Not providing his troops with winter clothing.

2) Not taking Moscow when it was doable.

3) Not treating well the local populations who were severely brutalized under the Soviet regime.

Had Hitler studied Napoleon as carefully as he studied Frederick the Great, he probably would have avoided invading the USSR altogether.