Cunt???

When is it okay to publicly call someone with whom you disagree a "cunt?
My fellow blogger Barcodeking, with whom I vehemently disagree but have heretofore allowed free range with his political comments, has resorted to calling musician Chryssie Hynde a cunt in his comments box at his Blog.
I presume it's because she had the temerity to insult Bush or his war efforts.
Whatever the reason, the word cunt offends me.
For a political adversary to use it tells me I am wasting my energy on someone who has so little tolerance for opposing viewpoints, he must resort to the depth of sexist guttersniping to bolster his position.
I can respect someone whose politics differ from my own.
I am for freedom of speech, and I defend even the most depraved American's right to voice his or her opinion.
When that person, however, feels the need to start calling women he doesn't even know cunts, I have the freedom to step away and consider the person beneath my dignity to debate.
Poor guy was holding his own, expressing his dimwitted views with great passion and vehemence. Too bad he got so threatened, his misogyny leaked out and busted him for what he really is.
Cunt, nigger, spick, raghead, it's all the same. It's hate speech.
When it emerges, credibility is shot and the need for common civility is voided.
End of story.