Utah Republicans have denied Robert Bennett, a very conservative three-term senator, a place on the ballot, because he’s not conservative enough. In Maine, party activists have pushed through a platform calling for, among other things, abolishing both the Federal Reserve and the Department of Education. And it’s becoming ever more apparent that real power within the G.O.P. rests with the ranting talk-show hosts.

News organizations have taken notice: suddenly, the takeover of the Republican Party by right-wing extremists has become a story (although many reporters seem determined to pretend that something equivalent is happening to the Democrats. It isn’t.) But why is this happening? And in particular, why is it happening now?

The right’s answer, of course, is that it’s about outrage over President Obama’s “socialist” policies — like his health care plan, which is, um, more or less identical to the plan Mitt Romney enacted in Massachusetts. Many on the left argue, instead, that it’s about race, the shock of having a black man in the White House — and there’s surely something to that.

But I’d like to offer two alternative hypotheses: First, Republican extremism was there all along — what’s changed is the willingness of the news media to acknowledge it. Second, to the extent that the power of the party’s extremists really is on the rise, it’s the economy, stupid.