Knowing that House Republicans are threatening to blow up the economy if Obama and congressional Democrats don’t agree to implement Mitt Romney’s economic agenda is less astonishing if you realize the key players in the House GOP are from Romney Country–not just districts carried by Mitt, but carried by Mitt by large landslides.

That’s what we learn from a Ryan Lizza column at New Yorker that focuses on what he calls the “suicide caucus”–the 8o House Republicans who signed the letter than ultimately forced John Boehner to go along with the “defund Obama” demand on the CR, which in turn has led to the “Romney ’13” demands attached to a debt limit bill.

Obama defeated Romney by four points nationally. But in the eighty suicide-caucus districts, Obama lost to Romney by an average of twenty-three points. The Republican members themselves did even better. In these eighty districts, the average margin of victory for the Republican candidate was thirty-four points.

In short, these eighty members represent an America where the population is getting whiter, where there are few major cities, where Obama lost the last election in a landslide, and where the Republican Party is becoming more dominant and more popular. Meanwhile, in national politics, each of these trends is actually reversed.

There are always, of course, rump caucuses in both parties that represent “base” areas atypical of the nation. But they don’t often control the party leadership, particularly on something as momentous as a debt default threat. As Rizza observes:

In previous eras, ideologically extreme minorities could be controlled by party leadership. What’s new about the current House of Representatives is that party discipline has broken down on the Republican side. On the most important policy questions, ones that most affect the national brand of the party, Boehner has lost his ability to control his caucus, and an ideological faction, aided by outside interest groups, can now set the national agenda.

I’ve argued to the point of ridiculous redundancy here at PA that the dominant political phenomenon in America today is the final conquest of the Republican Party by a conservative movement that has itself been radicalized (and I’ll keep making the point so long as alternative theories, such as some sort of equivalent “polarization”, remain popular). As we watch the country potentially slide towards a debt default, we’re at the very least seeing what that party might have accomplish had it won the White House and the Senate last year. And we’ll soon know what it’s willing to do in the absence of electoral victory to impose its will on the rest of us.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.