We're really discussing whether it's okay to punch a Nazi?
Seriously, it's never not okay to punch a Nazi. In fact, it should be a crime to not punch a Nazi when you happen upon one. Of a group encounters a Nazi, form an orderly line and take your shots one at a time.
Call the police, tell them you found a Nazi. The response should be: "did you punch him? No? Get to it before I arrest you both!" When the Nazi gets tossed in jail, his cell mates should be informed he is a Nazi, so they can punch him on the hour, every hour.