Progressive Democrats aren’t wasting a minute after the demise of TrumpCare. Buoyed by how the debate cemented a federal role in the health care system — it was untenable for Republicans to simply repeal Obamacare and return to the Bush-era status quo of health care as a privilege for the wealthy — they’re moving quickly to offer an actual alternative, a Medicare-for-all single payer system.

Bernie Sanders, who championed such a system throughout his presidential run, is going to introduce a bill, and this time he will have far more co-sponsors in the Senate than previous efforts. Elizabeth Warren voiced support for single payer at a town hall last week, and so did Rhode Island’s senators over the weekend. The deputy chair of the Democratic National Committee, Keith Ellison, is a Medicare for All co-sponsor, along with 72 House members. And numerous progressive organizations are on board with the push.

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In less realistic moments, some have wondered whether Donald Trump and his ideologically un-rooted supporters would come aboard the single payer train. While Trump has offhandedly promised universal coverage, you would go broke waiting for him to fulfill that. It makes no sense to expect Republicans who failed to repeal the current system because of fealty to free-market ideals to now turn over one-sixth of the economy to the government. It’s far more likely that Trump will burn down the current system to force through bad ideas like selling deregulated insurance across state lines, shifting costs to patients and adding work requirements to Medicaid.

That doesn’t make building support for single payer a useless exercise. In fact, it makes it more urgent, even responsible. Democrats have had a hard time the past several election cycles giving voters a specific reason to put them in charge again. As the minority party, this shouldn’t be difficult. You come up with a roster of ideas and paint an alternative vision of how the country could conduct its affairs.

Medicare for All has the benefit of being really easy to understand, leveraging an existing program that is reasonably popular. You can explain the underlying logic as well. The health system in America has devolved into a multi-sided market of competing monopolies seeking negotiating advantage. But you cannot get bigger than everyone. The government has a unique opportunity to clarify the system and use its bargaining power to give everyone the right to health care — at a more affordable cost.

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Defining principles directly and challenging the opposition in a war of ideas is simply how politics should work. It gives grassroots supporters confidence that their elected leaders share a vision for the future rather than just a discardable ideology of opposition. Republicans will call it a government takeover, and Democrats will call the GOP’s ideas heartless abandonment or cruel bankrupting of the sick. Let’s see who wins.

The problem has been that Democrats have made governing promises when out of power in the past only to abandon them when in a position to achieve them. The Employee Free Choice Act, which sought to protect workers’ right to unionize and was organized labor’s biggest priority, had the support of nearly every Democrat before Barack Obama; when Democrats could actually make it happen that support vanished. This breeds cynicism among the base, and if Democrats try the same thing with single payer the backlash will be even worse. That’s also true of savvy pronouncements to support single payer as an “opening bid” in a negotiation. Die-hard supporters don’t want to see their dream elevated expressly to be traded away.

It should also be understood that single payer is the easiest to explain of a host of similar measures that can bring sanity to health care markets. For example, in California, where the state legislature is pushing a single payer bill, gubernatorial candidate Gavin Newsom has vowed to campaign on a universal health care program — not just insurance — that has echoes of both managed care and the socialized medicine of Britain’s National Health Service. It’s modeled on a program called Healthy San Francisco that allows anyone, regardless of insurance or immigration status, to visit a community health center or public hospital as a “medical home” for primary and preventive care. These providers are publicly funded, mostly through an employer mandate; you can say that the health care professionals at the providers are public employees.

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Using medical homes, which can lower costs by ensuring early detection of problems before they get out of hand, as a baseline of universal coverage that can be topped off with a private system is similar to the way health care works in France.

Another idea would maintain a private health care industry while achieving most of the goals of single payer. That is known as all payer rate setting, and it’s what Martin O’Malley — remember him? — ran on in his presidential campaign. It got no traction, but the basic idea is that the government sets a distinct price for every medical procedure. Insurance companies no longer bargain with providers; they effectively band together to use their power to get the lowest possible rate.

This is actually how health care works in Maryland, in addition to Germany and Switzerland. Under O’Malley, Maryland instituted a global budget for hospitals, to reduce readmission rates and over-utilization of treatment as a way for health care providers to maximize profits. Insurance companies and hospitals actually like the certainty that comes with this system, despite the government intervention to set prices. It also attacks the tremendous billing waste in the system.

Plus, the pharmaceutical supply chain, which features unnecessary profit-taking by middlemen at nearly every stage, needs a major overhaul. Trump has discussed “competitive bidding” in Medicare with the Congressional Black Caucus. That’s actually too narrow. The oligopolist drug wholesalers and pharmacy benefit managers need to be broken up, and the markets made completely transparent on who pays what, or you’re not going to drive down costs for consumers.

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I didn’t mention lowering the Medicare eligibility age incrementally, or letting Americans buy into Medicare at cost, or even a public option to compete with private insurance. There are lots of ways to get to what a single payer system offers — a coherent market for health care that more affordably covers everyone than our current Rube Goldberg contraption. Standing on principles of true universal coverage is important and heartening. Whether it’s called single payer or just something that is consistent with those principles shouldn’t be a deal-breaker. But if Democrats think they can just talk up single payer to obtain power and then shuffle it off, they’re playing with fire.