"There is a distinct pattern in the quasi-political violence by 'lone nuts' in the US. With a only small handful of notable exceptions like John Hinkley, the 'lone nuts' have soaked up paranoid ideas from the right and attacked targets on the left. This has materially benefited the purposes of movements on the right, and they have not just continued to use the rhetorical devices that have aroused the crazies, they have used them more and more over time. I'm not prepared to say that inspiring madmen to attack the left is a deliberate plan of the Vast Right Wing Conspiracy, but it is clear that this is now a significant part of how politics in America works.
"If you make a study of the far right -- by which I mean not just the right wing folks of the Republican base, who make up the bulk of Tea Partisans, but the true far right like militiamen, Christian Identity, Operation Rescue, and the like -- you see that they talk a lot about building anarchic, leaderless movements in which ideas circulate through their media that inspire individuals and small groups to take dramatic actions that further the goals of the movement without any active coördination. That is their playbook, it's how most of the terrorist attacks on abortion providers came to happen, and mentally ill people are unmistakably part of the system that makes it work even if most of the folks in the movement are not mentally ill."