Sen. Kamala D. Harris (D-Calif.) speaks to students at Drake University in Des Moines on Monday. (Charlie Neibergall/AP)
Columnist

Will she or won’t she? Is Sen. Kamala D. Harris (D-Calif.) really going to run on Medicare-for-all the hard way – not as a buy-in for people who want to, but as a ban on private insurance?

On Monday, when Harris sat down for a CNN town hall discussion, the answer seemed to be yes, she’s doing the Full Bernie. On Tuesday there were rumors she’d walked it back. And by Wednesday, maybe the walkback was itself being walked back?

Washington wonks scrambled to make sense of it all, scrutinizing each new development like diviners hunched over a fresh pile of sheep entrails.

It may seem odd that so much attention was paid to such a drab little controversy. These are the bureaucratic details of a preliminary campaign plank from a Democratic presidential contender with only middling name recognition. “Fascinating” is not the first word that comes to mind.

But Washington wasn’t trying to divine the fate of Harris, exactly. It was trying to figure out where the Democratic Party is headed, and whether it’s going to take the rest of the country with it.

Medicare-for-all is one of those policies that sounds reasonably good – and polls reasonably well – until you get into those bureaucratic details. A recent poll from the Kaiser Family Foundation indicates that only 37 percent of Americans would support Medicare-for-all if it meant getting rid of private insurers or paying higher taxes. Support drops even further if it would in any way threaten the current Medicare program or lead to longer medical wait times.

If Harris settles on the proposal to nationalize the whole health-care insurance system, there will be plenty of time to debate whether this means longer waits or changes to Medicare. (Spoiler alert: yes to both.) But it does seem clear that she was talking about ending current private insurance. With a roughly $3 trillion annual price tag, any government replacement would necessarily entail much higher taxes on everyone.

Of course, single-payer advocates argue that the new taxes would merely replace current premiums, and that in the long run taxpayers would actually spend less on health care. The truth of that proposition is best left for another day. For now it’s enough to note something that voters clearly understand: Single-payer means immediate loss of their current insurance, and higher taxes, while the savings are more uncertain and, at best, would take years to materialize.

Which is why that moment during the CNN town hall was so important. Medicare-for-all is obviously catnip to the progressive base, and just as obviously deadly nightshade to the suburbanites whom Trump has driven out of the Republican Party. You know, the ones who propelled Democrats to control of the House by such handsome margins in November.

Those suburbanites may be unhappy with the U.S. health-care system, but they are, paradoxically, mostly quite happy with their insurance. Three-quarters of those making more than $75,000 a year rate their own coverage as “excellent” or “good.” They will not be eager to give it up in exchange for an uncertain alternative.

Democratic strategists are not unaware of this; neither are Democratic primary voters. But there’s a certain freedom in having Trump as an opponent — he’s so loathed in many quarters of the electorate that you can propose almost anything and still be pretty certain of those votes.

And yet, not entirely certain. If you force suburbanites to choose between having a lewd race-baiter in the White House and sacrificing their health-insurance coverage . . . or paying higher taxes . . . or many of the other disruptive things progressives want to do . . . well, maybe they decide the troglodyte is the lesser of two evils.

Furthermore, if Democrats nominate someone anathema to the soft suburbanite center, then Trump might feel free to move even closer to his devoted base. The effect could be a flat-out race to the far peripheries of the political spectrum, with bewildered moderates deciding whose base they’re more afraid of. It’s far from clear which party wins that race.

That’s a high-stakes bet for a political party to make. Nonetheless, Democratic politicians such as Harris seem to be screwing up their courage to take the plunge. The question is which way Democratic primary voters will bet: on some boring centrist who will never even try to deliver the radical change so many of them crave, or on the fire-breathing progressive who might accidentally deliver them another four years of Donald Trump.

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