"A man should never hit a woman." OK to hit a man?

Yeah, but you aren’t going to hit me over it, are you? I’d love to be utterly wrong on this one. If this woman did that to me in the elevator, or you, I wouldn’t blame someone for doing the same thing. What are you supposed to do? Stand there and take it? Curl up in a ball? I suppose putting one’s arm out would be acceptable, provided the arm goes out slowly.