Oh, there were other reasons, too: Trying to get rid of the insurance market would have obviously triggered a giant war with the insurers and other providers. But that is not what made single-payer fundamentally impossible, so clearly unworkable that the administration didn’t even seriously consider it. What made single payer impossible is the fact that tens of millions of voters have employer-sponsored insurance that they basically like, and they would freak out if you told them it was being replaced by a government-run national health-care program. Progressives could spend all the time they wanted talking about how awesome things are in Canada, but it wouldn’t have altered the fundamental political calculus. People are loss-averse; they worry more about losing what they have than they do about some unproven potential gain.

If Obamacare’s insurance reforms break the market, that calculus still won’t change: Most people will still have insurance they like, and they will not be willing to give it up in order to solve problems in the individual market — which now covers about 5 percent of the population and is expected to ultimately cover something over that. Even if the individual market functionally disappears, most people will still be covered, and most politicians will be unwilling to endorse a program that takes away what they have. There is no path to single payer from even a spectacular Obamacare implosion — for the same reason that there was no path to single payer before Obamacare was passed.