It goes without saying that the rollout of Obamacare was an epic disaster. But what kind of disaster was it? Was it a failure of management, messing up the initial implementation of a fundamentally sound policy? Or was it a demonstration that the Affordable Care Act is inherently unworkable?

We know what each side of the partisan divide wants you to believe. The Obama administration is telling the public that everything will eventually be fixed, and urging Congressional Democrats to keep their nerve. Republicans, on the other hand, are declaring the program an irredeemable failure, which must be scrapped and replaced with ... well, they don’t really want to replace it with anything.

At a time like this, you really want a controlled experiment. What would happen if we unveiled a program that looked like Obamacare, in a place that looked like America, but with competent project management that produced a working website?

Well, your wish is granted. Ladies and gentlemen, I give you California.

Now, California isn’t the only place where Obamacare is looking pretty good. A number of states that are running their own online health exchanges instead of relying on HealthCare.gov are doing well. Kentucky’s Kynect is a huge success; so is Access Health CT in Connecticut. New York is doing O.K. And we shouldn’t forget that Massachusetts has had an Obamacare-like program since 2006, put into effect by a guy named Mitt Romney.