Is punching a morally defensible option?

Yes, I am referring to a recent comment by Pope Francis and his description of a "normal response" to a curse which denigrates an other's mother. A punch may be a normal response, but that does not make it either an acceptable response or an action free of punitive consequences for the puncher on either moral or legal grounds. Once we open the door to a physical response to a perceived slight (intended or not), the offended party is in a position to calibrate their responding punch proportionate to the offense taken. For some, that is nothing short of the life of the other person. Do we want to return to duels at sunrise or gunfights at sundown?

I am not sure what Pope Francis meant in his off-the-cuff statement, but I do know how it is being interpreted in some quarters--something akin to a just war defense as his words are extrapolated to a national or sectarian religious insult. In the latter case, simply raising a serious theological question in a respectful manner can be construed as blasphemy.

Here is another take on the Pope's comment, which deserves thoughtful consideration.
http://www.theguardian.com/commentisfree/2015/jan/16/pope-francis-free-speech-charlie-hebdo

Pope Francis' comment strikes me as very much culturally driven. Let me try to explain. I grew up in an environment peopled by European immigrants and their descendants. The epitaph SOB was freely thrown about either directed at an individual or simply a free form curse. No one ever seemed to take it as an insult directed at one's mother. So if I don't speak Spanish and my cultural diversity is divisible only by one, I can be rightfully subjected to physical retribution for cursing in my mother tongue. When I was in the service, it was a very different story. Latino troops automatically interpreted this epitaph as an insult directed at their mothers, irrespective of the intent (in my judgment anyway) of the speaker. If the words were spoken by a peer, that peer was informed in no uncertain terms that offense had been taken.

I have a question for Pope Francis. I trust he will take his time in formulating an answer. What is an appropriate and proportionate response to a fatwa prohibiting snowmen?

http://www.csmonitor.com/World/Middle-East/Olive-Press/2015/0114/Seriously-a-fatwa-against-snowmen-Saudis-push-back-on-Twitter