The state of mind visible at recent right-wing demonstrations is nothing new. Back in 1964 the historian Richard Hofstadter published an essay titled, “The Paranoid Style in American Politics,” which reads as if it were based on today’s headlines: Americans on the far right, he wrote, feel that “America has been largely taken away from them and their kind, though they are determined to try to repossess it and to prevent the final destructive act of subversion.” Sound familiar?

But while the paranoid style isn’t new, its role within the G.O.P. is.

When Hofstadter wrote, the right wing felt dispossessed because it was rejected by both major parties. That changed with the rise of Ronald Reagan: Republican politicians began to win elections in part by catering to the passions of the angry right.

Until recently, however, that catering mostly took the form of empty symbolism. Once elections were won, the issues that fired up the base almost always took a back seat to the economic concerns of the elite. Thus in 2004 George W. Bush ran on antiterrorism and “values,” only to announce, as soon as the election was behind him, that his first priority was changing Social Security.

But something snapped last year. Conservatives had long believed that history was on their side, so the G.O.P. establishment could, in effect, urge hard-right activists to wait just a little longer: once the party consolidated its hold on power, they’d get what they wanted. After the Democratic sweep, however, extremists could no longer be fobbed off with promises of future glory.

Furthermore, the loss of both Congress and the White House left a power vacuum in a party accustomed to top-down management. At this point Newt Gingrich is what passes for a sober, reasonable elder statesman of the G.O.P. And he has no authority: Republican voters ignored his call to support a relatively moderate, electable candidate in New York’s special Congressional election.

Real power in the party rests, instead, with the likes of Rush Limbaugh, Glenn Beck and Sarah Palin (who at this point is more a media figure than a conventional politician). Because these people aren’t interested in actually governing, they feed the base’s frenzy instead of trying to curb or channel it. So all the old restraints are gone.

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