The question of what to do in any given circumstance has to do always with perception: how will people perceive my actions.
I think two messages need to be sent...one, we don't approve of your politics, but two, we accept you as people -- even when you don't accept us. I don't think not talking with republican administration is like Hitler...yes, they are bad people with ignorant ideals, but...like everyone...they are not sub-human...let's be good people, and turn the other cheek here. I think Michael sent both the above messages when he performed, talked with them after, but refused to take a picture with them. I think that was not only smart, but wise.
I cannot say strongly enough that refusing to entertain people is awful -- especially when your entertainment is subversive! Do your show...it'll stick around in their minds. It may even be a seed planted for change. I understand they may view us as subhuman, but doing the same to them does not help...it doesn't force them to see the humanity of the people they judge so harshly, and it does not open their eyes to the possibility that they have been misled.
"Fundamentalism means never having to say 'I'm wrong.'"
-- unknown