Bernie Sanders is releasing his latest single payer health care plan today, and while there are some small differences between this one and what he has proposed in the past, the biggest difference is that this time, he’s got lots of company. Fifteen Democratic senators are co-sponsoring his bill, including most of those considering running for president in 2020.

Support for some kind of universal coverage is now the consensus position among Democrats. And Sanders’ single payer plan is the one that has gotten the most attention, so it’s going to be the one against which other plans are measured.

But we have to understand this plan for what it really is: an opening bid. While he won’t say so himself, I doubt even Sanders believes that something in this form could pass through Congress. Even so, it represents an important strategic shift for the Democratic Party.

I’ll explain what that means in a moment, but here are the basics on what Sanders’ plan would do, based on a summary released by his office:

  • It establishes an (almost) true single payer system in which private and employer-based insurance is replaced by an expansion of Medicare to include nearly every American.
  • It does so over four years, lowering the Medicare eligibility age to 55 and insuring all children in the first year, then expanding the plan to include all citizens over the following three years.
  • It includes areas of coverage not currently offered by traditional Medicare, including dental, vision, and hearing aids.
  • It eliminates nearly all co-pays, coinsurance, and deductibles.
  • It allows the expanded Medicare system to negotiate drug prices, which Medicare is currently forbidden from doing.
  • It does not include nursing home coverage, which would continue to be covered under Medicaid, nor does it eliminate the VA or the Indian Health Service.
  • It would pay providers at current Medicare rates, which are lower than private insurance but higher than Medicaid.

This is a maximalist demand. It essentially says, “My plan is: everything. Not just covering everybody, but covering everything, without co-pays or deductibles. Is that realistic? Not really. But that may not be a problem.

One of the complaints people on the left had about both Bill Clinton and Barack Obama — in general, but specifically on health care — is that they gave away too much too quickly, often before negotiations even started. They were too focused on what Republicans or interest groups would never accept, so they moved their opening proposals three steps to the center, leaving the final negotiated solution much more conservative than it had to be. It would have been far better, this critique goes, if they had opened with a much more liberal proposal, then slowly given some ground and eventually arrived at a more liberal compromise.

It’s impossible to rerun history and decide if this critique is accurate. One thing we can say, however, is that Bernie Sanders, and the Democrats who have joined him, are taking a different approach.

If we say that this bill is unrealistic, we have to distinguish between two important kinds of realism. It’s politically unrealistic in that it would have no chance of passing unless there were a Democratic president, a Democratic House, and a Democratic Senate with the 60 votes necessary to overcome a Republican filibuster — and probably not even then. There would be a highly organized, well-funded campaign against it from nearly every health care interest group. The political obstacles would be extremely difficult to overcome.

But you might say, so what? This bill is being offered in 2017, when there’s a Republican president, a Republican House, and a Republican Senate. It doesn’t have to be realistic. It can be a way of saying, “This is what as Democrats we think a perfect health insurance system would look like.” In that sense, this bill could be extremely useful, since it will communicate the Democratic vision to voters in a way that isn’t too hard to understand. It’s basically the Medicare your parents get, except even better, since it fills in the gaps in current Medicare and you wouldn’t be paying premiums or coinsurance, which Medicare recipients currently do.

The other question is whether this bill is substantively realistic, and that one may cause you some more concerns. This would be the most generous health insurance program in the world, even more so than Great Britain’s National Health Service. While there would be some near-immediate cost savings on administration, it would take longer than many people realize to force down all the prices that make American health care so expensive. The transition to this plan would be much more complicated than Sanders admits.

But right now, it’s fair to put many of those questions aside. Hillary Clinton was right to criticize Sanders’ maximal vision in 2016, because she thought she was going to be president and would have to actually try to pass whatever she proposed. Now the situation is very different. Democrats can posit this plan as what they’d like in a perfect world — but also say that they’d accept a more practical, incrementalist path that would eventually achieve many of the same goals.

Once the Sanders plan is in wide circulation, if I said, “How about an expansion of Medicaid to become a basic plan for all adults, while private insurance would still exist to offer supplemental coverage?”, you might now say that sounds pretty reasonable. If you did, it would mean that Sanders had effectively widened the debate and made what not long ago would have seemed like radical ideas look like moderate compromises.

There’s no guarantee that would happen. For one thing, Sanders isn’t saying how much this plan would cost or how he’d pay for it, and Republicans will probably try to ignore what single payer insurance offers and just repeat “It’ll be a $98 septillion tax increase!!!” until the entire enterprise is discredited. If so, Sanders’ opening bid might end up failing to move the debate substantially to the left.

But offering a more aspirational vision like this one is something Democrats haven’t really tried before, at least not collectively. And it just might work.