I disagree with Jay.
I don’t believe that it’s likely that “the Arizona massacre will hurt the Republican party and the Tea Party, stopping or slowing their momentum.” This isn’t Oklahoma City all over again. Reason 1: McVeigh wasn’t as crazy as and had a more coherent political purpose than Loughner. Reason 2: Tying McVeigh to the militia movement was less of a stretch than tying Loughner to Palin.
The Oklahoma City bombing didn’t help Clinton politically just by helping him discredit libertarian extremism. It helped him because it allowed him to find his voice as the national-healer-in-chief at a time when he had been written off as politically irrelevant. Obama isn’t in the same position (and I do not believe he has the same capabilities, either).
Already the polls show that the public doesn’t buy the “discourse” discourse. If I were President Obama, I would be very careful about pursuing the media/liberal line of argument about “civility.” The Left has, if you will, poisoned the atmosphere around that word to the point where even anodyne and true statements from the president about the value of civility in public life would be taken as shots at the Right. And I’d think there could be at least a small backlash and not much upside.