Ms. Warren’s answer just seems evasive: I believe dismissive annoyance would be a better posture. She needs to say “Out of pocket costs for fully insured, middle-class taxpayers will be lower. That’s what matters, and that’s what I’m promising. How we get there is a detail.”

That won’t make the problem of paying for M4A go away, though. There is no guarantee that the promise of lower cost can be kept until the government has “negotiated” with the healthcare industry. Yes, prices can be controlled, but not supply. We do not draft doctors. In this country, the opportunities for smart STEM students are endless. Medicine attracts its share because medicine pays well. We don’t know what it will cost to maintain the supply of care at the level maintained by the subsidy that private payers currently give to public ones.

I’m not denying that some docs do their thing because they have a calling. I’m saying that as a policy matter, getting enough docs requires enough compensation, and Medicare does not pay well enough at current rates to stock the lake. As it is, there are places in this country with no doctors. M4A, without an upward adjustment in rates, will make that problem worse. Supply, not cost, is the wild card in M4A, and none of its proponents seem willing even to acknowledge that problem. (John Delaney tried to raise the point, but he was the wrong messenger. Bernie/Warren voters aren’t any smarter than Trump voters; they just have different scapegoats.)