It’s a long way from 2012, but the field of GOP presidential contenders is already narrowing. First came South Carolina Gov. Mark Sanford’s wrong turn on the Appalachian Trail, then Friday’s announcement by Sarah Palin that she was resigning the Alaska governorship.

Palin’s future remains uncertain, but it’s hard to see how her cryptic and poorly drafted resignation speech positions her for a presidential run. Nonetheless, her departure presents a good opportunity to reflect on the Right’s affinity for presidential contenders who — how to put this? — don’t exactly overwhelm you with their intellectual depth.

It’s one thing to reject liberal elitism. It’s another thing to become so consumed with annoying liberals that you cleave to anyone they mock, and make presidential virtues out of shallow policy knowledge and lack of intellectual curiosity.

As a vice-presidential candidate, Palin was a new and appealing presence, and she gave a terrific convention speech. But she never showed any hint that she was qualified for the office. Much of the fervor surrounding her candidacy was based on right-wing resentment of snooty liberal intellectuals: Every time the Left denigrated her intelligence, Republicans bristled, and rallied around her.

It’s easy to understand conservatives’ ire at the nastiness Palin’s family endured. And the Right is right to scoff at the notion that “the best and the brightest” make ideal leaders. Woodrow Wilson, the worst president in American history, ran Princeton University before he rose above his competence and nearly wrecked the country. Our current president, a former University of Chicago Law School professor, isn’t doing so hot himself.

William F. Buckley had a point when he said he’d “rather be ruled by the first 500 people in the Boston phonebook than the faculty at Harvard.” But you can take that point too far–and conservatives have.

Their logic seems to go something like this: Jimmy Carter was smart, and a bad president; Reagan went to Eureka College and the intelligentsia sneered at him, yet he was a good president. Liberal elitists sneer at Bush and Palin, too, therefore they’d make marvelous presidents.

But unlike either Bush or Palin, Reagan was fiercely interested in ideas. Anyone who’s looked at “Reagan in His Own Hand,” the volume that reproduces his handwritten 1970s radio speeches, knows how sharp and skilled our 40th president was as a writer and thinker. And it must be said that none of Reagan’s speeches featured as many screaming ALLCAPS and exclamation marks as Palin’s Friday speech, which included lines like, “LIFE is about choices!”

Bush and Palin are certainly brighter than the Left would have you believe. John Kerry did a better imitation of an intellectual than Bush, who couldn’t be bothered, but Bush’s grades at Yale were higher than Kerry’s. And it takes smarts to rise, as Palin did, from small-town mayor to governor. Yet if either Bush or Palin ever developed a deep interest in national affairs or foreign policy — the stuff of the presidency — they were utterly unable to convey it.

Conservatives undermine their movement when they fetishize inarticulateness as “plain speaking.” Surely President Bush could have benefited from some of Obama’s verbal facility in 2005, when he tried to convince voters to support private accounts for Social Security.

And Republicans hurt themselves when they make resentment of coastal elites a major campaign theme. There are, after all, quite a few electoral votes on the coasts, and the GOP lost nearly all of them in 2008.

Last November, Obama won a majority of Americans making more than $200,000 a year–and it’s hard to believe they voted for him because they yearned for higher taxes. Perhaps some of them recoiled from the notion that they weren’t quite “real Americans.”

In 1954, liberal critic Lionel Trilling announced that conservatism in America had declined into a collection of “irritable mental gestures which seek to resemble ideas.” The next year, Bill Buckley proved him wrong by founding National Review, the magazine that made conservatism an intellectual force once again.

In the years that followed, when NR endorsed candidates, it picked those who, like Goldwater and Reagan, knew what they stood for and could explain it clearly. That’s a smart approach in any era.