The best summary I've seen so far of Sarah Palin's role as a dirty bomb in the culture war comes from Adam Serwer:
The conservative movement at this point basically reminds me of people who thought 50 Cent was going to be the greatest rapper ever because he had been shot nine times, not because he could actually flow. Let's face it, 50 is wack. He's wack like Sarah Palin is wack. But like Sarah Palin, he had a story that reflected the cultural values of realness and authenticity that hip-hop fans had come to place above actual rhyming ability. Most of these fans are not from the hood in the same sense that the folks at The Corner are not Real Americans(tm) from "flyover country," and they can't yet understand what the obsession with authenticity is doing to a movement they supposedly love.
I hope that doesn't make John McCain the conservative politico version of Dr. Dre. I like Dre.