Glenn Beck is writing a novel. It's about a group called "the Founders Keepers" starting a civil war. In a classic Beckian touch, he's given it a title designed to enrage smart people who find him repellent: The Overton Window.

"The Overton Window" is a political science term that describes how "radical" ideas are mainstreamed. It was originally used to describe how think tanks could most effectively influence policy, by gradually making politically untenable proposals gradually sound more and more reasonable, until they're eventually "common sense."

Liberal bloggers discovered this term a few years ago, and it elegantly explains everything that's gone wrong with America over the last 40 years. Glenn Beck's national prominence on a major cable news network is possible only because talk radio has spent years pushing "acceptable" "mainstream" public discourse rightward, and Fox has been normalizing extreme right-wing rhetoric for years.

And now, in 2010, Glenn Beck is just at the far end of acceptable debate, Sean Hannity's pathological lying and antisemitic guests spreading conspiracy theories seem a little bit more mainstream, and suddenly Bill O'Reilly is comfortably in the center. And Shep Smith is a liberal, because he is uncomfortable with the government torturing people to death.

Glenn Beck naming his Ayn Rand (another radical fringe lunatic who's been successfully made mainstream over the last 40 years) ripoff novel after the political science theory that made his success possible is just a lovely thought, isn't it?