Political columnist Michelle Goldberg argued over the weekend in Tablet Magazine that even though Jared Lee Loughner, the alleged shooter of Rep. Gabrielle Giffords and murderer of six others, was “clearly in the grip of delusion rather than any coherent ideology,” it is still reasonable to explore whether the paranoid and nativist political climate cultivated by far-right groups and, to an extent, mainstreamed by the Tea Party helped lent=d Loughner the impetus to try to kill not just anyone but specifically a Democratic, Jewish congresswoman. Writes Goldberg:
Loughner was probably too insane to have really participated in anti-Semitic politics, or, for that matter, in the Tea Party. But it is important to note that Giffords has been relentlessly demonized by the right, the rhetoric around her charged with violence. And such rhetoric is dangerous precisely because of the effect it can have on the unhinged. Loughner was crazy, but he was also responsive to certain real-world political currents, particularly the right’s nightmare vision of federal power run amok.
Others have made similar cases: I would particularly recommend James Fallows‘s and George Packer‘s takes (insists the latter, “The massacre in Tucson is, in a sense, irrelevant to the important point”).
Or, you know, you could compare arguments such as those above to blood libel. (More responsibly and persuasively, you could assert that politics had little if anything to do with it, and you could welcome even the most heated discourse as a pressure valve that heads off most violence.)