Last Thursday there was a rally outside the U.S. Capitol to protest pending health care legislation, featuring the kinds of things we’ve grown accustomed to, including large signs showing piles of bodies at Dachau with the caption “National Socialist Healthcare.” It was grotesque  and it was also ominous. For what we may be seeing is America starting to be Californiafied.

The key thing to understand about that rally is that it wasn’t a fringe event. It was sponsored by the House Republican leadership  in fact, it was officially billed as a G.O.P. press conference. Senior lawmakers were in attendance, and apparently had no problem with the tone of the proceedings.

True, Eric Cantor, the second-ranking House Republican, offered some mild criticism after the fact. But the operative word is “mild.” The signs were “inappropriate,” said his spokesman, and the use of Hitler comparisons by such people as Rush Limbaugh, said Mr. Cantor, “conjures up images that frankly are not, I think, very helpful.”

What all this shows is that the G.O.P. has been taken over by the people it used to exploit.

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?