An ad hominem argument, also known as argumentum ad hominem (Latin: "argument to the man", "argument against the man") consists of replying to an argument or factual claim by attacking or appealing to a characteristic or belief of the person making the argument or claim, rather than by addressing the substance of the argument or producing evidence against the claim. The process of proving or disproving the claim is thereby subverted, and the argumentum ad hominem works to change the subject.

It is most commonly used to refer specifically to the ad hominem abusive, or argumentum ad personam, which consists of criticizing or personally attacking an argument's proponent in an attempt to discredit that argument.

Wha? You got the definition right, but you didn't cite an example from the editorial to prove your point which was, apparently, that Hitch argued fallaciously. Just because Hitch criticized Romney, that's not an ad hominem attack. An ad hominem attack would look like this:

"Dinesh D'Souza says that Christianity ennobles humanity and has lead to the enlightenment of mankind and the establishment of western democracy, but D'Souza is a wonky pinhead and you can't believe anything that comes out of his mouth."

I could be wrong, but I think that this post was meant to be a response to an earlier post made by a user named puhlease.

If not, then I don't understand it either.

Doh! You're right. I get it now. My apologies to rosalindavenue.

The name calling is so over the top, I'm tempted to think Hitchens posted it himself!