Newt Gingrich appeared on CNBC last night and argued, with a straight face, that the so-called "Fast and Furious" controversy was part of an elaborate ploy to enact gun control. He wasn't kidding.

As Gingrich sees it, the Bush and Obama administrations deliberately attempted misguided sting operations so there would be deadly gun violence along the U.S.-Mexican border, which in turn would repulse the American mainstream, which in turn would create a demand for gun-control legislation, which in turn would cause Congress to pass gun-control laws, which in turn would cause a breakdown of Second Amendment rights.

Well, you might be thinking, Newt Gingrich is, you know, Newt Gingrich. Surely more sensible and more responsible figures in American politics see this conspiracy theory as ridiculous. But therein lies the point: this crackpot idea is the basis for the "controversy" itself.

Yesterday, when I called the Fast and Furious story "kind of silly," I received a nice note from a conservative reader, asking why I was so dismissive of the "scandal." I believe Rachel's segment last night answered that question extremely well. For those of you who missed the show and can't watch clips online:

"[T]he theory here is the Obama administration [is] being super lax in gun control as a conspiracy in order to be super tough on gun control. What? [...]

"If you care to look, yes, this is exactly as crazy as it seems. This is a very strange and implausible and perhaps impossibly implausibly, cockamamie, make-your-cell-phone-out-of-aluminum-foil thing that has animated the right for more than a year now."

Bob Herbert told Rachel last night, "[T]he idea this had something to do with the Obama administration wanting to undermine Second Amendment rights is madness of the highest order."

And yet, this nuttiness has been fully embraced by many House Republicans, many Senate Republicans, Fox News, Newt Gingrich, the NRA, and some deeply strange folks on far-right blogs and talk radio. To put it mildly, it's disconcerting.