I don't think the intent of the OP was to debate where the term originated from, but rather that Obama chose to use it after calling for civility. I don't really think there's much to argue there. He meant the term to be offensive, and it would seem he succeeded to a degree.
Well, exactly. We've got 25 pages of liberal deflections and not one legitimate explanation for why the President of the United States CHOOSES to debase American citizens and then lecture to them about "civility".
The guy's a low-life, no-class, flinger of monkey poo, and unworthy of his office.
And his supporters are no better. You'd think people would be less willing to compromise their own integrity than to stand up for such an obvious hypocrite... but hey, after the past year and a half, I can't say I'm really surprised.