DEPARTMENT OF INMATES, ASYLUMS…. Arguably the scariest aspect to modern Republican politics is the blurring of the line between the party mainstream and the unhinged, right-wing party fringe.

So I was intrigued the other day to see this Politico piece, explaining that the conservative establishment is “taking aim for the first time at the movement’s extremist elements.”

The move has been cast by some conservatives as a modern version of the marginalization of the far-right, anti-communist John Birch Society during the reorganization of the conservative movement spearheaded by William F. Buckley Jr. in the 1960s and 1970s.

“A similar effort will be required today of conservative political and intellectual leaders,” former Bush speechwriter Michael Gerson wrote in his column in The Washington Post. “It will not be easy. Sometimes it takes courage to stand before a large crowd and proclaim that two plus two equals four.”

But for Gerson and other conservatives, this is not just an intellectual exercise. They have a very specific political goal: to deprive Democrats and their allies of a potentially potent weapon to use against the GOP in November.

“I don’t believe we should be giving [extremists] a platform or empowering them to do anything based off their conspiracy theories,” said Ned Ryun, president of American Majority, “because they give the left ammunition to try to define the tea party movement as crazy and fringy.”

This makes a lot of sense. If I were a Democratic strategist, I’d likely invest quite a bit of energy in characterizing the modern Republican Party as stark raving mad, and its base as having gone hopelessly insane. There’s probably real value in reminding mainstream voters that there are a lot of nutjobs running the GOP’s circus, and rewarding the party with more power, control, and influence may not be a good idea.

If a growing number of leaders on the right believe this is a potential p.r. problem for Republicans, and are taking steps to separate the party from the crazies, this would be a positive development for everyone.

The problem is, some of those who want to keep the extremists at bay are themselves extremists.

The attempt “to clean up our own house,” as Erick Erickson, founder of the influential conservative blog RedState, puts it, is necessary “because traditional press outlets have decided to spotlight these fringe elements that get attracted to the movement, and focus on them as if they’re a large part of this tea party movement. And I don’t think they are.” […]

Erickson has advised new tea party organizers on how to avoid affiliations with extremists and this month banned birthers — conservatives who believe that Obama was not born in the United States and is, therefore, ineligible to be president — from his blog. (He has long blacklisted truthers, those who believe that the U.S. government was complicit in the Sept. 11 terrorist attacks — a conspiracy theory with devotees across the political spectrum.)

“At some point, you have to use the word ‘crazy,’” said Erickson.

Yes, Erick Erickson wants to help rid conservatives of the extremist. As Simon Maloy explained, “That’s the same Erick Erickson who called retiring Supreme Court Justice David Souter a ‘goat f–king child molester,’ who called two sitting U.S. senators ‘healthcare suicide bombers,’ who praised protesters for ‘tell[ing] Nancy Pelosi and the Congress to send Obama to a death panel’ (before furiously backtracking), and attacked President Obama’s Nobel Prize as ‘an affirmative action quota.’”

My suspicion is that some news outlets that are receptive to Republican messages will buy the line — the GOP is moving to the mainstream. They’ll even support it by pointing to things like CPAC scrapping a panel discussion on the president’s birth certificate (while accepting Birchers as an official co-sponsor of the event).

All the while, fringe ideas and extremist personalities continue to drive the party and its message. For crying out loud, last week, Rep. Steve King (R-Iowa) offered praise for a lunatic who flew an airplane into a building, and faced no criticism from his party whatsoever. Indeed, a year from now, if Republicans take the House majority, Steve King will be the chairman of the Judiciary Committee’s panel on Immigration, Citizenship, Refugees, Border Security, and International Law — and no one in GOP circles will find that insane.

Rep. Trent Franks (R-Ariz.) said African Americans were better under slavery, and he too received no criticism from his party at all — and is also positioned to be a House Judiciary subcommittee chairman if Republicans are in the majority next year.

The idea of Republicans and conservatives in general purging the radicals seems sensible, right up until one appreciates the fact that it’s too late — the inmates are already running the asylum.

Our ideas can save democracy... But we need your help! Donate Now!

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.