Leading Republicans appear to be nerving themselves up for another round of attempted fiscal blackmail. With the end of the fiscal year looming, they aren’t offering the kinds of compromises that might produce a deal and avoid a government shutdown; instead, they’re drafting extremist legislation — bills that would, for example, cut clean-water grants by 83 percent — that has no chance of becoming law. Furthermore, they’re threatening, once again, to block any rise in the debt ceiling, a move that would damage the U.S. economy and possibly provoke a world financial crisis.

Yet even as Republican politicians seem ready to go on the offensive, there’s a palpable sense of anxiety, even despair, among conservative pundits and analysts. Better-informed people on the right seem, finally, to be facing up to a horrible truth: Health care reform, President Obama’s signature policy achievement, is probably going to work.

And the good news about Obamacare is, I’d argue, what’s driving the Republican Party’s intensified extremism. Successful health reform wouldn’t just be a victory for a president conservatives loathe, it would be an object demonstration of the falseness of right-wing ideology. So Republicans are being driven into a last, desperate effort to head this thing off at the pass.

Some background: Although you’d never know it from all the fulminations, with prominent Republicans routinely comparing Obamacare to slavery, the Affordable Care Act is based on three simple ideas. First, all Americans should have access to affordable insurance, even if they have pre-existing medical problems. Second, people should be induced or required to buy insurance even if they’re currently healthy, so that the risk pool remains reasonably favorable. Third, to prevent the insurance “mandate” from being too onerous, there should be subsidies to hold premiums down as a share of income.