The precise moment of McCain's abasement came, would you believe, not at some news conference or on one of the Sunday shows but on "The View," the daytime TV show created by Barbara Walters. Last week, one of the co-hosts, Joy Behar, took McCain to task for some of the ads his campaign has been running. One deliberately mischaracterized what Barack Obama had said about putting lipstick on a pig -- an Americanism that McCain himself has used. The other asserted that Obama supported teaching sex education to kindergarteners.

"We know that those two ads are untrue," Behar said. "They are lies."

Freeze. Close in on McCain. This was the moment. He has largely been avoiding the press. The Straight Talk Express is now just a brand, an ad slogan like "Home Cooking" or "We Will Not Be Undersold." Until then, it was possible for McCain to say that he had not really known about the ads, that the formulation "I approve this message" was just boilerplate. But he didn't.

"Actually, they are not lies," he said.

Actually, they are.

McCain has turned ugly. His dishonesty would be unacceptable in any politician, but McCain has always set his own bar higher than most. He has contempt for most of his colleagues for that very reason: They lie. He tells the truth. He internalizes the code of the McCains -- his grandfather, his father: both admirals of the shining sea. He serves his country differently, that's all -- but just as honorably. No more, though.

I am one of the journalists accused over the years of being in the tank for McCain. Guilty. Those doing the accusing usually attributed my feelings to McCain being accessible. This is the journalist-as-puppy school of thought: Give us a treat, and we will leap into a politician's lap.

Not so. What impressed me most about McCain was the effect he had on his audiences, particularly young people. When he talked about service to a cause greater than oneself, he struck a chord. He expressed his message in words, but he packaged it in the McCain story -- that man, beaten to a pulp, who chose honor over freedom. This had nothing to do with access. It had to do with integrity.

McCain has soiled all that. His opportunistic and irresponsible choice of Sarah Palin as his political heir -- the person in whose hands he would leave the country -- is a form of personal treason, a betrayal of all he once stood for. Palin, no matter what her other attributes, is shockingly unprepared to become president. McCain knows that. He means to win, which is all right; he means to win at all costs, which is not.

At a forum last week at Columbia University, McCain said, "But right now we have to restore trust and confidence in government." This was always the promise of John McCain, the single best reason to vote for him. America has been cheated on too many times -- the lies of Vietnam and Watergate and Iraq. So many lies. Who believes that in Afghanistan last month, only five civilians were killed by the American military in an airstrike, instead of the approximately 90 claimed by the Afghan government? Not me. I first gave up on the military during Vietnam and then again when it covered up the death of Pat Tillman, the Army Ranger and former NFL player who was killed in 2004 by friendly fire.

McCain was going to fix all that. He was going to look the American people in the eyes and say, not me. I will not lie to you. I am John McCain, son and grandson of admirals. I tell the truth.

But Joy Behar knew better. And so McCain lied about his lying and maybe thinks that if he wins the election, he can -- as he did in South Carolina -- renounce who he was and what he did and resume his old persona. It won't work. Karl Marx got one thing right -- what he said about history repeating itself. Once is tragedy, a second time is farce. John McCain is both.

cohenr@washpost.com