Another way to look at this is to apply a version of Jeff Bezos's Regret Minimization Framework: project yourself decades into the future and read about yourself in a history book.

If you truly believe Trump is an unprecedented threat to democracy in the league of Stalin, how would you feel telling your children that "it was just business" when you kept on a partner who was part of his campaign apparatus?

I don't think IBM is particularly proud of their management during the 1930's. No one knows or cares about the personal views of the people behind those decisions, just what they led IBM to do.