It’s not even clear how much Democrats who have embraced single payer would agree on if the policy debate moved from abstract discussion to nitty-gritty details. Locked out of power in Washington, Democrats have no ability to implement single payer. That gives liberal lawmakers the freedom to talk up the idea of government-administered, taxpayer-funded health insurance that would provide universal coverage, without necessarily needing to know exactly how they would achieve it.

“Democrats are essentially using ‘single payer’ as an easy shorthand to convey that they want a health-care system that works better and costs people less,” said Sherry Glied, a former health policy advisor to the George H. W. Bush, Clinton and Obama administrations. “But just invoking the concept on its own doesn’t say much about policy specifics. To some extent, this is the flip-side of what Republicans did by advocating for repeal and replace [of the Affordable Care Act] when Obama was president. For Democrats, single payer may even be a more attractive proposition when there’s a Republican president since they don’t have to deal with the hard trade-offs that would be at stake if a bill could actually pass.”