I had dinner the other night with a Republican-leaning independent who was despondent over John McCain’s choice of Alaska Gov. Sarah Palin as his running mate. She had been looking forward to supporting McCain as a fiscal conservative with a deep understanding of foreign relations. But all she could now see was that picture of Palin’s pregnant 17-year-old looking defiant and stupid as she held mom’s fifth baby.

Many religious conservatives are jubilant. They regard Palin as a swell choice because her high-schooler was going to have the baby. The line sent my friend into shock. This is not a matter of abortion politics, she said, but of managing one’s own affairs.

“Don’t they have birth control up in Alaska?” she asked.

If that view has any currency among Republican-leaners, you can imagine what other independents are thinking. Or disaffected supporters of Hillary Clinton. Barack Obama’s recent pandering toward the Clinton holdouts didn’t do the Democrat a fraction of the good that McCain is doing him. McCain’s apparent belief that dangling any woman before diehard Clinton fans would win them over may be optimistic.

Until now, one could counter the Democrats’ argument that a McCain presidency would amount to a third term for Bush. After all, McCain is a deficit hawk. He cares about the environment. Many pro-choice voters were willing to overlook McCain’s generally anti-abortion stance on the belief that he didn’t really care about the issue. And the widespread concern regarding McCain’s age could have been assuaged by the choice of a competent vice president.

Then who does McCain pick for VP? A 44-year-old who parades her dysfunctional family as a poster-child for conservative values. Who has virtually no foreign policy experience. Who as mayor of an Alaskan town of 6,700 hired lobbyists to reel in $27 million in federal pork. That’s $4,030 of the U.S. taxpayers’ money per resident. We thought McCain wanted to close down the trough.

Democratic House Speaker Nancy Pelosi has five children, but she waited until they were grown before she ran for high political office. Palin returned to the job three days after giving birth to a special needs child, all the while her 17-year-old is entertaining a lover. And what about plans to have the girl wed the stud, author of some very unromantic remarks on Facebook? Note that she’s been pregnant for five months and still no matrimony. These nuptials couldn’t be a last-minute political move, could they?

Palin supporters insist that her out-of-control home life will resonate with many American families. Yes, if they’re from Mars or perhaps on welfare.

What a McCain presidency now promises is another four years of Terri Schiavo and other artifacts of the cultural right. You remember Schiavo’s husband having to fight the Bush administration and Republican Congress to remove his wife — in a vegetative state for 15 years — from life support. It’s four more years of national humiliation as our leadership undermines the teaching of evolutionary science, and if something happens to John McCain, opposes stem-cell research.

One tries to untangle McCain’s political calculations. The Schiavo case, creationism and similar excesses appeal to a passionate but small slice of the electorate. They are one reason voters are booting Republicans out of power. So while some religious conservatives may be “energized” by the Palin pick, most everyone else is revolted.

You can’t figure McCain. He had been doing well up to now — holding even with Obama in a dreadful year for Republicans and building support among the independents who call the shots in swing states. This Palin deal makes you question not only his judgment, but — if he really had vetted Sarah Palin — his sanity.

Froma Harrop is a Providence Journal columnist. Her e-mail address is fharrop@projo.com.