A reader notes something significant in the assassin's reading list. What unites it is paranoia, a sense of others controlling you, of conspiracy theories and government plots, of illegitimate government and its agents of control:
Loughner had very incoherent, hard to classify beliefs. But they were clearly paranoid and conspiratorial.
The conspiratorial or paranoid style is very much alive in our political discourse. Naturally, it's not just a right-wing phenomenon. I live in Berkeley where a fraction of people sincerely think 9-11 was an "inside job" pulled off by the "Bush Regime". There's also the ChemTrail crowd that thought the Republican government used planes to dump toxins on liberal areas to make us sick, disrupt pregnancies, and sap our will to resist. Etc., etc., So yeah, that paranoid style is alive on the fringes of the American left.
But with the Right, it's a bit different. The paranoid and conspiratorial style is much more mainstream, especially with Beck and Fox. On Fox, there are shadowy links between Soros, the Tides Foundation, and other liberal causes that aim to bring America down. Obama is at once fascist and a socialist. Don't forget Palin's dark insinuations about Obama's ties with terrorists and HCR's agenda to impose of Death Panels. Of course, you have questions about Obama birth certificate sadly mainstream when Republican representatives and candidates claim it's still an issue.
My own view is that this is a moment for sane conservatives to control their jerking knee and reflect a little on what they have enabled. If politics is warfare, people will die.