on-air with Rachel Maddow, her producer warned me that one of the questions might be: "You and John Amato have a new book coming out this spring titled Over the Cliff: How Obama's Election Drove the American Right Insane. Insane?"

Easy reply: A-yup.

Unfortunately, she never actually asked it. Now, of course the title is a bit of hyperbole in that it's hard to say whether one could accurately call this a clinical insanity (more on that in a bit). But what John and I and the rest of the C&L team have been observing over the past year, and have compiled into a coherent and (we hope) thought-provoking study, is simply the descent into madness of an entire political bloc. It's a verdict that, in the past couple of weeks, has been not just vindicated but manifested in news events.

Sometimes the insanity turns up anecdotally, as in this e-mail I was forwarded from a friend:

I got a call from my daughter that the whole family went out to dinner. While eating dinner my granddaughter gets a text message from one of her classmates. The text is: "It's God's responsibility to forgive Obama but it's our responsibility to arrange the meeting between God & Obama." My granddaughter is 12 years old, black and in the sixth grade at an elementary school [near Atlanta]. The classmate who sent the text is also twelve years old but white. When my daughter saw this message, she texted this 12-year-old back and asked her what she meant by arranging the meeting between God and Obama. The 12-year-old essentially said it meant to kill Obama.

Or it turns up in the Facebook page with a "joke" wishing for God to take Obama:

A recently created Facebook page reads, "Dear Lord, this year you took my favorite actor, Patrick Swayzie (sic). You took my favorite actress, Farah (sic) Fawcett. You took my favorite singer, Michael Jackson. I just wanted to let you know, my favorite president is Barack Obama. Amen."

Most often these days, it turns up at Tea Parties and related right-wing events, such as the April 19 D.C. armed march, featuring gun-nut rhetoric like that from Media Matters Action Network in the video above.

Some of this, as the Violence Policy Center recently explored in a study titled "Lessons Unlearned: The Gun Lobby and the Siren Song of Anti-Government Rhetoric" [PDF file] is being deliberately whipped up by right-wing organizations, notably the gun lobby.

And some of it is merely free-floating right-wing angst, stirred up by sources ranging from Glenn Beck to Ron Paul to FreedomWorks. I especially enjoyed this video from the April 15 Tea Party protest in D.C., compiled by the fine folks at NewLeftMedia:

I especially loved the woman who informed us that President Obama plans to ban fishing, didn't you?

The insanity also manifests itself in Republican governors' new fondness for Guy Fawkes as a model for Tea Partiers to follow. As Josh Marshall put it, "I find this completely bewildering. The Republican Governors Association is embracing the mantle of a 17th century radical who tried but failed to pull off a mass casualty terrorist attack to kill the King of England and all of Parliament.... Nothing shocks me anymore. But this shocks me."

Adds Steve Benen:

It's a reminder that the Republican mainstream made a right turn at scary, and have arrived right at stark raving mad.

Even for Beltway folks like Marc Ambinder are wondering: "Have Conservatives Gone Mad?" Ambinder's answer: A-yup.

I want to find Republicans to take seriously, but it is hard. Not because they don't exist -- serious Republicans -- but because, as Sanchez and others seem to recognize, they are marginalized, even self-marginalizing, and the base itself seems to have developed a notion that bromides are equivalent to policy-thinking, and that therapy is a substitute for thinking.

It is absolutely a condition of the age of the triumph of conservative personality politics, where entertainers shouting slogans are taken seriously as political actors, and where the incentive structures exist to stomp on dissent and nuance, causing experimental voices to retrench and allowing a lot of people to pretend that the world around them is not changing. The obsession with ACORN, Climategate, death panels, the militarization of rhetoric, Saul Alinsky, Chicago-style politics, that TAXPAYERS will fund the bailout of banks -- these aren't meaningful or interesting or even relevant things to focus on. (The banks will fund their own bailouts.)

This disconnect from reality is occurring because the American Right is insistent on it. Indeed, one of the reasons that I'm perfectly comfortable calling the American Right "insane" -- even if you couldn't call them "insane" in the legal or clinical sense -- is that one of conservatives' outstanding characteristics is their perfervid insistence on believing things that are provably untrue, even when presented with insurmountable and indisputable evidence.

If, per Einstein, doing something repeatedly and expecting different results defines "insanity," then similarly, insisting on believing in things that are provably untrue is also a definable sign of it. Which is, in fact, what I was going to tell Maddow.

Here, just for starters, are the Top 10 Provably Untrue Things Tea Partiers Believe In:

1. The Birth-Certificate Conspiracy.

2. Death Panels.

3. Obama Is A Muslim/Socialist/Fascist.

4. Obama Is Going To Take Away Our Guns.

5. Obama Is Raising Our Taxes.

6. Fascism Is A Left-Wing Phenomenon.

7. Global Warming Is A Hoax.

8. Two Million People Were at 9/12 March.

9. 16,000 New IRS Agents.

10. The Tea Parties Are a Non-Partisan, Broad Grassroots Movement.

That really is the definition of insanity.