Obama sticks the shiv in Cheney

I gasped as I watched a smiling Obama unload this in his White House Correspondent's Dinner speech:

Dick Cheney was supposed to be here but he is very busy working on his memoirs, tentatively titled, "How to Shoot Friends and Interrogate People." (Laughter.)

That looks like carefully calculated (and calibrated) payback for Cheney's loud, frequent assertions that Obama is risking the country's security by abjuring the Cheney torture regimen. But does it sound like Obama? Am I crazy -- is this just bonhomie, in a class with comparing Biden to an eager puppy dog? Or did Obama deliver the deadliest insult leveled by one national politician against another in recent memory? He implicitly summed up Cheney's career as an exercise in treachery and torture.