Two articles do a great job describing the bleating birthers/teabaggers/gun-toting/Nazi obsessive town hall-crashers:
So the birthers, the anti-tax tea-partiers, the town hall hecklers -- these are "either" the genuine grass roots or evil conspirators staging scenes for YouTube? The quiver on the lips of the man pushing the wheelchair, the crazed risk of carrying a pistol around a president -- too heartfelt to be an act. The lockstep strangeness of the mad lies on the protesters' signs -- too uniform to be spontaneous.
They are both.
If you don't understand that any moment of genuine political change always produces both, you can't understand America, where the crazy tree blooms in every moment of liberal ascendancy, and where elites exploit the crazy for their own narrow interests. [...]
The instigation is always the familiar litany: expansion of the commonweal to empower new communities, accommodation to internationalism, the heightened influence of cosmopolitans and the persecution complex of conservatives who can't stand losing an argument. My personal favorite? The federal government expanded mental health services in the Kennedy era, and one bill provided for a new facility in Alaska. One of the most widely listened-to right-wing radio programs in the country, hosted by a former FBI agent, had millions of Americans believing it was being built to intern political dissidents, just like in the Soviet Union.
Rick Perlstein: In America, Crazy is a Preexisting Condition
One cause is a kind of conceit that says, "My vision of the way the country should be run is the only sound and permissible vision. Stray from it and there will be unprecedented calamity."
That is one element.
The other is the inability to digest or tolerate the fact of their electoral defeat. One chief feature of a democracy is the rule of law, but the president's opponents feel they owe no obedience to the law because if a man was elected that they despised, then clearly the election could not, at bottom, be legal. In their eyes, they represent what is morally most admirable about America, and the only way a whole class of sterling, morally superior people, clinging to an identical core of the most admirable convictions -- the only way they could be defeated would be because they were victims of the workings of sinister, underhanded forces of fraud, deceit and misrepresentation. They did not lose the election, it was stolen from them by selfish scum.
So the losers' resentment thus becomes not an expression of mean-spirited, ill-informed and humiliated spite, not an ambition to regain power, but a kind of rescue effort aimed at restoring the rightful state of things in the land. In other words, Obama's critics are not blindly petty and vindictive, eaten alive by mindless rancor, they are heroic.
The people who hate Obama and who like to call him a communist actually share a certain similarity of disposition with communism. In communism, it was a central tenet that the Party had a monopoly on the truth and this required complete loyalty and subjugation on the part of the members. To hold back your complete endorsement to your group's agenda did not mean that you simply disagreed with it. It meant something more menacing -- a kind of moral failure, an excessive pride, a stubborn perversity of will that prevented you from seeing the truth. Obama's critics believe they enjoy the same monopoly of virtue, and feel that what today's desperate conditions require is intolerance -- you can with good conscience cast aside your scruples. The importance of your mission and your certainty of being right relieves you of the burden of having to be truthful, restrained or respectful of the facts. The nobility of your cause means any weapon can be used against the enemy -- vile harangues, calumnies, slander, abuse, libel -- you don't have to use nimble skill in reasoning to outwit your target, you don't have to have full command of the smallest intricacies of the issues to confute his claims -- you have only to stand and shout your opponent down, drown him out, bury him under a landslide of slights, epithets and insults. After all, you have the courage of a person with a crowd at his back.
Richard Sale: Moral Absolutes and Politics