The key to understanding how John McCain chose Sarah Palin as his running mate was provided by The New York Times last weekend when it described an episode in which he “tossed $100 chips around a hot craps table.”

Gambling with his presidential candidacy is McCain’s right. Gambling with the country McCain says he puts first is another thing entirely. And Thursday night’s vice presidential debate took place at precisely the moment when a majority of American voters decided that having Palin in line for the presidency is more than a little bit scary.

Polls released on the eve of the debate found that for the first time, majorities of Americans declared Palin unprepared to be president if she were called upon to assume the office. In a Washington Post/ABC News Poll, 60 percent of voters said Palin lacked the experience to be president, up from 45 percent in the first week of September. In a Pew Research Center survey, 51 percent said she was not qualified for the presidency, up from 39 percent at the beginning of the month.

And if part of Palin’s task is to win women over to the Republican ticket, she clearly isn’t doing the job. The Pew poll gave Barack Obama a lead of 54 percent to 37 percent among women.

Palin’s trajectory might be analogized to one of those subprime mortgages. The terms at the beginning are highly attractive. But as time goes on, mortgage holders start to pay dearly, and many default. Thursday’s debate was a desperate effort by Palin to keep McCain’s investment in her from going under.

Here’s the paradox: The McCain campaign’s exertions to prevent Palin from doing damage by keeping her interviews and spontaneous exchanges with voters to a minimum have only underscored the fact that she is not up to the job. As Katie Couric’s interviews have shown, Palin is profoundly uninformed and appears to have given little thought to issues that matter. That’s true even of abortion, a question on which she has strong views.

Palin’s insistence that there is a right to privacy in the Constitution must have made even her staunchest supporters in the right-to-life movement wince. Robert Bork, a movement hero, denied that a constitutional right to privacy existed, a major reason he lost his Supreme Court confirmation battle. “The court has used its invented privacy right exclusively to enforce sexual freedoms,” Bork has complained, calling its invention “hubris.” Palin was oblivious to her own side’s core assertion.

She has also brought out the very worst in McCain, forcing him to — I don’t use this word lightly — lie about her. In an interview broadcast on Wednesday, National Public Radio’s Steve Inskeep asked McCain if there would be “an occasion where you could imagine turning to Gov. Palin for advice in a foreign policy crisis?”

McCain replied: “I’ve turned to her advice many times in the past. I can’t imagine turning to Sen. Obama or Sen. Biden, because they’ve been wrong. They were wrong about Iraq, they were wrong about Russia.”

“Many times in the past”? McCain met Palin only twice before he selected her. What McCain said could not be true.

And McCain’s backers signaled their fear that Palin would fail in the debate by trying to discredit the event in advance.

Although it has been known since at least July that debate moderator Gwen Ifill was writing a book on “Politics and Race in the Age of Obama,” the usual right-wing attack squad waited until just two days before Thursday’s encounter to mount a campaign to the effect that Ifill’s book project turned her into a biased moderator. The idea is that everyone but Palin is responsible for Palin’s shortcomings.

The core issue, of course, is the contrast between how Obama and McCain chose their running mates. Say what you will about Joe Biden, no one loses sleep at the idea of him in the Oval Office. Obama picked a vice president more likely to help him in governing the country than in winning the chance to do so.

As for McCain, he found himself in a political hole and threw the dice with Palin. At the time of her selection, voters were often compared with “American Idol” watchers who put personality and stage presence above everything else. But it turns out that Americans take the presidency very seriously. Surviving 90 minutes on a stage with Biden will not turn Palin into a plausible president.

E.J. Dionne’s e-mail address is postchat(at)

© 2008, Washington Post Writers Group

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