How about this thought experiment:
What if the victim had been a girl, and he had ripped off her bra because she dressed like a beatnik? No groping, nothing sexual, just mean.
If that is different, why?
Also, the analogies to using alcohol and marijuana ring quite hollow. Those are personal experiments, not harassment of others.
This conduct is surely not disqualifying by any stretch – I don’t think anyone is saying that it is. But the contrary position — that it deserves no attention at all — is not realistic. This is one of the things that goes into the basket of judging character, and Romney’s recent behavior, his marriage, etc., that voters can and should look at to get a picture of the man who wants to be our president.