Yet there Krugman was, in his column the next day, quoting Clarence Dupnik to blame "the vitriolic rhetoric that we hear day in and day out from people in the radio business and some people in the TV business." Krugman specifically blames the "eliminationist rhetoric" that comes "overwhelmingly" from the Right. The column is dressed up with data and anecdotes about death threats and vandalism, but not a single fact that connects Jared Lee Loughner to Krugman's right-wing villains.

So why was Krugman, apart from simple political rancor, so eager to blame this mass-murder on the Tea Party Right? Since his peers considered him a radical lefty, why not blame the violent rhetoric of hard-core leftists against Blue-Dog moderates like Giffords, who took a conservative stance on nearly everything but health care reform? Or since Loughner, reportedly an atheist, exclaimed his refusal to "trust in God," why not blame the over-heated rhetoric of the New Atheists? Or why not blame the Truther movement, since Loughner believed the government was behind 9/11? My point is not actually to make these accusations, but they would have been equally justified, and arguably more justified by the facts, than the accusation that Krugman positively makes. So why does Krugman, on the basis of no evidence whatsoever, make the specific accusation he does?

There are two reasons that seem to be escaping commentary so far.

First, Krugman and his fellow travelers have been waiting to tell this story ever since the summer of 2009, when the argument over health care reform began in earnest, and even earlier. They had a sort of Political Mad-Lib in hand. They knew the narrative they wanted to tell—that conservative politicians and commentators were inciting violence against liberals—and were just waiting to fill in the names and places.

Krugman himself admits this. He has been "expecting something like this atrocity to happen . . . ever since the final stages of the 2008 campaign." He cites "the crowds at McCain-Palin rallies," which the Left accused of being particularly vicious and violent. Then, in the midst of the extended health care debate from the summer of 2009 into early 2010, liberals were upset about the anti-reform protests and warned that a rash of violence against the supporters of Obamacare was imminent. When the bill passed, a number of Democratic lawmakers, as well as two Republicans, faced threats and vandalism. Elected Democrats spoke of domestic "terrorism." Surely comments such as those of Michelle Bachman, when she said her supporters should be "armed and dangerous" on the issue of the energy tax, were "fanning the flames with coded rhetoric"? Tea Partiers were called racist, homophobic, and xenophobic; they were blamed for Obama-Hitler posters carried by far-left Lyndon LaRouche supporters, and for signs carried by "Tea Party crashers" seeking to discredit the movement.