Top 10 lists about Sarah Palin's attack on David Letterman are already being written but really there is only one reason Palin should relent—she’s not a good enough politician to play.

Palin has spent much of her public life in feuds with the state legislature, with her ex-brother-in-law, with John McCain’s staff, with Levi Johnston’s family. An early fight with the chairman of Alaska’s Oil & Gas Commission paved the way to the governor’s office. She mostly wins, especially when the target is as easy, say, as a high-school dropout whose mother is under federal indictment. The Johnstons make the Palins look like Rockefellers.

Isn’t making a federal case out of a tasteless joke exactly what the right-wing loves to ridicule feminists for doing?

But picking a fight with a trained comedian, refusing to accept his apology, and continuing to battle after the white flag is shown reveals a complete lack of political sophistication.

Letterman apologized at unprecedented length for a comment about Palin’s recent trip to New York. There was, he said, “One awkward moment for Sarah Palin at the Yankees, during the seventh-inning stretch, her daughter was knocked up by Alex Rodriguez.” To which the Palins shot back: “Laughter incited by sexually perverted comments made by a 62-year-old male celebrity aimed at a 14-year-old girl is… disgusting.”

Who said anything about a 14-year-old girl? Not Letterman. That would be… the Palins. It turns out it was Willow, not Bristol, who went to the baseball game. But who knew that until the Palins brought this “disgusting” comment so painful to their younger daughter to the attention of the 300 million people not tuned into David Letterman?

Letterman's joke was indeed tasteless—he even owed A-Rod an apology. But I doubt there was another soul in the world who didn’t understand the joke to be about the older Palin daughter, who lapped Jamie Lynn Spears as the most famous pregnant teen in the world once she was trotted out at the Republican National Convention in August. Not that Bristol should have been left at home in the dark, but if you want a “zone of privacy” around your daughter, do you have her appear on stage with her then-fiancé hinting at prospects of a White House wedding waving to the crowd like Charles and Diana of the Klondike?

And exploiting Bristol as an unwed teen mother didn’t stop with the campaign. Back in Wasilla, where Bristol could have been sheltered and given space to rebuild her life, the Palins arranged to send her out like a vaudeville act, traveling the country to talk about teenage pregnancy under the sponsorship of Candie’s, a clothing company known for sexually provocative outfits for tweens.

The Bristol “do as I say tour” had a rocky start once she admitted that abstinence was not “realistic”—apparently she was against it before she was for it. Note to mom: When you become the ambivalent poster child for unwed motherhood, you attract off-color jokes.

Letterman’s eight-minute expression of regret on Wednesday night was almost as riveting as the one where Letterman talked about his heart surgery with the doctors and nurses who cared for him.

“I’m telling you, I recognize that these are ugly. These are borderline... [but] these are not jokes made about her 14-year-old daughter. I would never, never make jokes about raping or having sex of any description with a 14-year-old girl.” The audience tittered. He remained serious. “Yes, maybe these are questionable because the girl, excuse me, who was knocked up is 18 years old... Am I guilty of poor taste? Yes. Did I suggest that it was OK for her 14-year-old daughter to be having promiscuous sex? No.” He invited her on the show.

Palin was so intent on maintaining her fury, real or manufactured, that she used Letterman’s apology to escalate, saying through the spokeswoman for SarahPac that she wouldn’t want to boost his show’s ratings by appearing on it: “Plus, it would be wise to keep Willow away from David Letterman.” Did Palin call Letterman a pedophile?

Palin appears to be squandering her leftover fame from the campaign on staying famous, settling scores, making headlines over petty concerns, securing the cover of People magazine for Bristol. She could have been the keynoter at the Republicans' biggest fundraiser of the year on Monday night but instead played a coy, will-she-or-won’t-she game for weeks.

So in the end, Palin spent a week when she could have given a substantive speech, laid out a political philosophy, or choosing the issues she wants to run on, deliberately misinterpreting a bad joke, in the process dragging yet another child into the celebrity scrum.

And by the way, isn’t making a federal case out of a tasteless joke exactly what the right wing loves to ridicule feminists for doing?

Palin’s final mistake was to refuse Letterman’s invitation for a late-night make-up appearance, a moment on the studio sofa every bit as good as make-up sex for smoothing over any scandal, misunderstanding, or affront, real or imagined. It worked for Hugh Grant, Bill Clinton, and recently John McCain, who had come in for weeks of ridicule after giving Letterman a phony excuse for canceling.

Instead, she chose to get the last word on the Today show Friday morning, damning “a so-called comedian” for eroding “a young girl’s self-esteem” with a “joke about statutory rape.”

If she keeps saying so, perhaps the charge will stick, most likely with the daughter she is trying to protect. As for being a serious presidential contender, she should have said it on Letterman.

This is 2009. Real politicians do late night.

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