HOW did a deadly shooting spree by a disturbed young man with the typically inscrutable politics of political killers turn into a crazy referendum on the state of American political discourse?

Mere minutes after the identity of the alleged Tucson gunman hit the wires, partisans began a reprehensible scramble to out Jared Loughner as ideological kin to their political opponents. Actually, well before that time, some left-leaning opinionators began suggesting that Sarah Palin's now-infamous crosshairs map probably had something to do with the shootings. At the very least, intemperately fiery right-wing rhetoric probably had something to do with creating a cultural "climate" unusually encouraging to would-be assassins. Before anybody really knew anything, some people seemed to have become convinced that if not for the heavy weather of partisan antagonism summoned by intemperate tea-party types, Gabrielle Giffords would not have got a bullet through the brain.

In a blog item on Saturday, before any significant details about Mr Loughner's motivations had come to light, Paul Krugman wrote:

You know that Republicans will yell about the evils of partisanship whenever anyone tries to make a connection between the rhetoric of Beck, Limbaugh, etc. and the violence I fear we're going to see in the months and years ahead. But violent acts are what happen when you create a climate of hate. And it's long past time for the GOP's leaders to take a stand against the hate-mongers.

This struck me as irresponsibly premature, and one might have thought that, given a little more time and information, Mr Krugman would change his tune, or at least turn down the volume. Nope. In today's column on America's alleged "climate of hate", Mr Krugman reports that he's been "expecting something like this atrocity to happen" since 2008, conjures in his fevered imagination a "rising tide of violence", and spots his hated political foes behind it all:

[I]t's the saturation of our political discourse—and especially our airwaves—with eliminationist rhetoric that lies behind the rising tide of violence. Where's that toxic rhetoric coming from? Let's not make a false pretense of balance: it's coming, overwhelmingly, from the right.

What's more, unless the ranting right reins in the kind of talk that leaves Mr Krugman "with a sick feeling in the pit of my stomach", "Saturday's atrocity will be just the beginning." Welcome to crazytown, my friends, where it does not seem crazy to disgorge toxic, entirely evidence-free rhetoric about the mortal threat of toxic rhetoric. Does the man honestly think he's helping?

Ezra Klein, who also indulged in a bit of irresponsible early speculation about the role of conservative rhetoric in Mr Loughner's rampage, today points us toward some actually useful information about the killer's mens rea. Nick Baumann of Mother Jonesspoke with Bryce Tierney, a friend of Mr Loughner's from school, who offered the following explanation of Mr Loughner's beef with Representative Giffords:

Tierney, who's also 22, recalls Loughner complaining about a Giffords event he attended during that period. He's unsure whether it was the same one mentioned in the charges—Loughner "might have gone to some other rallies," he says—but Tierney notes it was a significant moment for Loughner: "He told me that she opened up the floor for questions and he asked a question. The question was, 'What is government if words have no meaning?' " Giffords' answer, whatever it was, didn't satisfy Loughner. "He said, 'Can you believe it, they wouldn't answer my question,' and I told him, 'Dude, no one's going to answer that,'" Tierney recalls. "Ever since that, he thought she was fake, he had something against her."

Got that? Ms Giffords failed to tender a satisfactory reply to "What is government if words have no meaning?", was judged a fake, and...and Mr Loughner shot her in the head.

At this point, there is simply no sound reason to believe this deranged young man was fired up by "toxic" or "eliminationist" conservative rhetoric from Michele Bachmann or whomever. Why are we even having this conversation? It's nuts. It's offensive. Is there any, you know, evidence that political rhetoric is now more vitriolic or incendiary than usual? Maybe there is, but I know of none. A feeling in Mr Krugman's gut doesn't cut it. Doesn't it seem at least as likely that a 22-year-old would be inspired to an act of high-profile atrocity by violent video games or films? As far as I know there's no evidence of that, either.

Mr Loughner's obsession with language as a form of control seems rather less like Glenn Beck or Sarah Palin than Max Stirner, Michel Foucault, or even left-leaning linguists such as George Lakoff and Geoffrey Nunberg. Our own Johnson discusses speculation about the possible influence of one David Wynn Miller. But nobody's going to try to smear Max Stirner, George Lakoff, or David Wynn Miller in the pages of the New York Times by recklessly associating their teachings with the tragedy in Tucson because, well, that would be completely bonkers and, more importantly, Max Stirner, George Lakoff, and David Wynn Miller didn't just recapture the House.

Anyway, let Ross Douthat's intelligently measured column be an example to Mr Krugman of the responsible, reasonable, non-toxic analysis he demands, but utterly failed to deliver.