We cannot know for sure yet, but Jared Loughner seems to have been motivated by extreme disdain for authority and the “phonies” around him. For Dylan Klebold and Eric Harris and Cho Seung-Hui that manifested itself in shooting up peers at high school or college. This turned into an assassination (self-described by Loughner as such).

I think we can do a lot of good focusing on the paucity of mental health resources for at-risk youth in this country, and the easy availability of truly deadly weapons well outside what is needed for self-protection or game hunting, in response to this tragedy. Nevertheless, I think we can just quote the GOP Senator to whom Politico cowardly granted anonymity to understand that at least some segment of that party feels a twinge of guilt:

“There is a need for some reflection here – what is too far now?” said the senator. “What was too far when Oklahoma City happened is accepted now. There’s been a desensitizing. These town halls and cable TV and talk radio, everybody’s trying to outdo each other.”

Whether Loughner was merely a deranged kid who would latch onto whatever philosophy he could find, or whether he actively sought out far-right conspiracy theories, I don’t think you can deny the general milieu of anti-government rhetoric that just so happened to nestle in the very state where Loughner lived. People are not fully separate from their environment. There’s no real reason for Loughner to have turned to Giffords as a seed for his anti-authoritarian beliefs rather than some other figure of authority – a teacher at the school which rejected him, or the military recruiting center which rejected him as well.

The truth is that Loughner’s motivations are kind of irrelevant to this point – there’s a low level hum of eliminationism, of demonization, and it’s mostly coming from the conservative side. The last political event that took a violent turn occurred when a Rand Paul volunteer stomped on the head of a MoveOn member outside a debate. And the list of violent rhetoric and political violence over the past couple years is quite literally a mile long.

If Loughner had any connection to this at all, it came from deep on the fringe. But the presence of it in the mainstream of the conservative movement – from the Speaker of the House (who said of fellow Ohio Congressman Steve Dreihaus, “He may be a dead man” after voting for the health care bill) on down – motivates that fringe to take it even further. The Patriot movement and right-wing militias have become emboldened in recent years. And mentally ill people like Jared Loughner can pick up on this raging rhetoric, and fit it into their paranoid constructs.

We’re finally starting to see people take this seriously; it’s sad that it took such a terrible tragedy to get to that point. The New York Times editorial board and one of its columnists signaled their discomfort with a “climate of hate” pushed from the right in recent years. Jim Clyburn acknowledged that such rhetoric was coming home to roost with this incident. And E.J. Dionne urged conservative leaders to take on their own party, not just in blind quotes in Politico but in a way befitting leadership.

The point is not to “blame” American conservatism for the actions of a possibly deranged man, especially since the views of Jared Lee Loughner seem so thoroughly confused. But we must now insist with more force than ever that threats of violence no less than violence itself are antithetical to democracy. Violent talk and playacting cannot be part of our political routine. It is not cute or amusing to put crosshairs over a congressional district.

Liberals were rightly pressed in the 1960s to condemn violence on the left. Now, conservative leaders must take on their fringe when it uses language that intimates threats of bloodshed. That means more than just highly general statements praising civility.

There’s a fair bit of humility now in Washington, but the real test will come in the next few weeks, to see what transpires. I don’t support blocking the political speech of anyone, but that’s a separate point from being able to condemn the most irresponsible speech when it gets made. Conservatives have abandoned the rhetorical playing field to their most noxious elements. They have the responsibility to take it back. It sure would reflect a better understanding of themselves than guilt-ridden finger-pointing at whoever calls them out on their behavior.