On Thursday, I stated the obvious: HHS Secretary Kathleen Sebelius's resignation was timed to follow news of Obamacare's surprising success signing up 7.5 million people for private insurance.

Conventional wisdom was that Sebelius would resign back in October or November, when Healthcare.gov was a mess and the White House needed a scapegoat. Like many others, I thought Sebelius — and a few others — should be fired.

But for better or worse, President Obama doesn't like to fire people amidst crises, even if the crises are partly their fault. And so Sebelius's resignation, coming on the heels of a rush of good news for Obamacare, is evidence that the White House considers the Obamacare crisis is over. With 7.5 million people (and rising!) signed up for the insurance exchanges and 3.5 million people (and rising!) signed up for Medicaid the law is likely here to stay — which means the White House can finally exhale, and begin changing the team that runs it.

This blindingly obvious analysis made a lot of Obamacare critics very, very angry. Sen. Ted Cruz, for instance, took the column on in a speech in New Hampshire:

If you listen to Democrats, if you listen to the media - although, I repeat myself - they will tell you there is no hope. They will tell you we cannot turn this around. They will tell you you cannot stop Obamacare. They will tell you that Kathleen Sebelius resigning is a result of Obamacare's success. Well if that's true, then I hope every Democrat will follow her path and resign, as well!

Sen. John Cornyn was pithier.

This is a joke, right? "@voxdotcom: Kathleen Sebelius is resigning because Obamacare has won http://t.co/LUxv3Q0XUQ" — JohnCornyn (@JohnCornyn) April 12, 2014

Republicans used to talk about Bush Derangement Syndrome. Washington Post columnist Charles Krauthammer defined it as "the acute onset of paranoia in otherwise normal people in reaction to the policies, the presidency — nay — the very existence of George W. Bush." Republicans like Krauthammer understood that BDS helped the Bush administration in two ways: it fired up their supporters and it distracted liberals from more modest, but effective, critiques.

Today, the right struggles with Obamacare Derangement Syndrome

Today, the right struggles with Obamacare Derangement Syndrome: the acute inability to see Obamacare as anything but a catastrophic failure that the American people will soon reject. For those suffering from ODS, all bad Obamacare news is good news, and all good Obamacare news is spin. In this world, delays of minor provisions in the law prove that the entire structure is collapsing, while surges of millions of people enrolling in insurance don't prove anything at all.

ODS has kept Republicans from updating their mental model of how Obamacare is doing. To them, the law's disastrous rollout proved that it was doomed. The fact that it recovered beyond anyone's expectations — literally, not a single analyst or policymaker I spoke to in December thought it credible that the exchanges would sign up 7 million by April, much less 7.5 million — hasn't made much of an impression.

Today, Republicans are thrilled by Sebelius's resignation: It means that the Obama administration needs to get her successor, OMB Director Sylvia Matthews Burwell, confirmed by the Senate. And that's an opportunity for Republicans to relitigate the many failures of Obamacare.

So long as Ted Cruz is promising Obamacare can be stopped, no Republican can outline a plan to tweak it

But it's coming at a moment when Obamacare's successes are getting tougher and tougher to deny. The law signed up more than 7.5 million people in the exchanges, more than 3.5 million people in Medicaid, and it led millions more to get health care through their employers or directly through insurers. Premiums are lower than the Congressional Budget Office predicted when the law passed, and insurers are already thinking about how to compete for applicants in 2015. The White House has a much better story to tell than anyone — including me — thought possible in December.

There are still many good critiques to make of Obamacare. But Republicans don't want to critique Obamacare. They want to stop it. Repeal it. They want to make it the hill big-government liberalism dies upon. And those in the party who know better continue to be cowed by those in the party who don't. So long as Ted Cruz is going to New Hampshire promising that Obamacare can be stopped, no Republican can step before the faithful and outline a plan for how it can be tweaked.

The irony of this is that Obamacare's successes are, in many cases, conservatism's successes. The individual mandate is a conservative idea — and it's working. Liberals were skeptical that private insurers would compete on price even absent a public option — but they are. High-deductible health plans are a longtime conservative solution for health costs — and Obamacare is spreading them far and wide. But conservatives can't take credit for any of this, much less build on it.

For the White House, the new hearings present an opportunity. Public opinion always lags a bit behind policy reality. Obamacare, weirdly, became more popular in its disastrous first weeks. But then its numbers plummeted as people realized Healthcare.gov really was a disaster. Now that Obamacare is recovered the White House needs to somehow get that message out to the public — and even to liberals. That's a tough job. Obamacare's unexpectedly impressive enrollment numbers aren't getting nearly as much coverage as its early disasters.

The irony is that Obamacare's successes are in many cases conservatism's successes

The other problem for the White House is that many think Obamacare is basically working despite the Obama administration's best efforts. The roll-out really was a disaster, the law remains unpopular, and estimations of the Obama administration's competence are still low. The public would gladly flock to a political party that had a real plan for improving Obamacare, and a serious claim to being able to manage it more professionally. Luckily for the Obama administration, ODS ensures Republicans are still far, far away from being that party.

Update: More good news for Obamacare...