In two days, Senator Bernie Sanders is going to introduce a single-payer healthcare bill in the Senate. This bill already has the support of some major Democratic senators, and it will move the single-payer debate further forward than any other legislative effort to date. But it will also move the debate from the abstract to the concrete, if Bernie’s bill provides the proper level of detail. Because average Americans are going to be considering the concept through the filter of: “How is this going to affect my pocketbook?” Democratic supporters need to be ready with solid, easy-to-understand answers to this basic question. Hopefully, Sanders will provide these answers on Wednesday, so the public can truly begin to make an informed choice on the matter.

It is interesting to note how far the Democratic Party has come on this issue in a relatively short period of time. Eighteen months ago, during the 2016 Democratic presidential primary season, Bernie Sanders was building support for single-payer while Hillary Clinton heaped scorn on the idea and used scaremongering against it. To her, it was just one more “free pony” that Bernie was offering up that he (in her opinion) could never deliver for the American people.

This is not an overstatement of her position at all. Clinton tried to equate Bernie’s support for single-payer with the Republican “repeal and replace Obamacare” efforts (which, at the time, were mostly just “repeal” efforts). She tried to paint Bernie’s position as one of first destroying Obamacare, and then entering into a congressional debate about single-payer ― which she warned would leave millions in the lurch. Sanders had never advocated such a strategy, but that didn’t stop Clinton from essentially putting these words in his mouth. Here is Clinton from an Iowa campaign event, at the end of January, 2016:

I want you to understand why I am fighting so hard for the Affordable Care Act. I don’t want it repealed. I don’t want us to be thrown back into a terrible, terrible national debate. I don’t want us to end up in gridlock. People can’t wait. People who have health emergencies can’t wait for us to have a theoretical debate about some better idea that will never, ever come to pass.

Hillary then shamelessly used a mother of a child with brain cancer to make this point, inviting her onto the stage to talk about how Obamacare’s end to “pre-existing conditions” had saved her daughter’s life. Clinton then added:

People can’t wait. Your daughter calls and says she has a mass in her forehead, you can’t wait. You quit your job to take care of your sick daughter ― something I think a lot of us can relate to ― you can’t wait.

Clinton used the fear of a “terrible, terrible national debate” to imply that Bernie’s first step would have been to end Obamacare ― a position he never held. She used more fear to imply that children with health emergencies would have to “wait” while the “theoretical debate” caused “gridlock.” She darkly warned that single-payer healthcare would “never, ever come to pass.”

That was then. This is now. Five Democratic senators have already co-sponsored Bernie’s single-payer bill: Cory Booker, Kamala Harris, Jeff Merkley, Elizabeth Warren, and Sheldon Whitehouse. Also, Kirsten Gillibrand has endorsed the concept of “Medicare For All” but has not yet signed on to Bernie’s bill. The “Washington Post” today pointed out how many of these people have shown an interest in (or widespread support for) a 2020 presidential run. A year and a half ago, the Democratic frontrunner said single-payer would never, ever come to pass, and in less than two years there will be a Democratic presidential primary contest underway. The issue is fast becoming if not the default Democratic position, at the very least a big litmus test. That is a remarkable evolution in attitude in such a short time. In the same week that Hillary Clinton will release a book decrying Bernie’s “free ponies,” Sanders will be introducing the biggest progressive change of them all in the United States Senate. And he’s already garnering support from some of the people most interested in running to defeat Donald Trump next time around.

Of course, as always, the devil is going to be in the details. Single-payer would be a massive change the entire country would have to go through. Monthly premiums to insurance companies would somehow become taxes paid to the government ― which would affect everyone’s paycheck in some way or another. The level of taxation required for single-payer to be successful is the biggest unanswered question. The answer to this question will allow the public to see how many people would benefit from the change and how many people would wind up paying more.

The Sanders bill needs to answer all the big single-payer questions, in detail. Although the bill is not going to get a floor vote for a long time to come, it will be the benchmark for any future legislation, and it will also provide all the talking points for the opposition to use for years to come. So the details are going to be critical, and they better be honestly laid out for the public to consider.

Single-payer is a great concept, and right now the American public is more inclined to at least consider the idea than they’ve ever been before. In January, a Pew poll showed 60 percent of the public agreed that “the government has a responsibility to provide healthcare coverage for all.” This was up from 51 percent last year, showing the public may be moving as fast as the Democratic Party candidates on the issue.

However, few Americans really understand what changes single-payer healthcare would require. There has been no concentrated advertising campaign against the idea (or for it, for that matter). Republicans have their own internal problems with healthcare (their failure to “repeal and replace Obamacare”), and so they haven’t spent any energy attacking single-payer. All that may be about to change in a big way, once Sanders releases a concrete plan.

Single-payer has been seriously proposed in two states (that I am aware of), Vermont and California. In Vermont, they gave up because they considered the tax it would require to be too high (or, perhaps more accurately: “too high a price to pay politically”). In California, they didn’t even get that far because the bill that emerged from the state senate didn’t even attempt to show how it would be paid for. Which is why Bernie’s bill better have a solid financial foundation, laying out exactly what will be required to pay for such a system ― both from the government, and from people’s paychecks.

The single-payer debate is about to begin in earnest. Bernie Sanders laying a proposal on the table will be a milestone in this debate. It will be used as a marker in future negotiations over details, so it better lay all the details out.

This debate is well worth having. As single-payer proponents love to point out, the entire rest of the developed world manages to provide single-payer healthcare to its citizens, so there is no real reason why we should not be able to do the same thing. But proponents should be ready to explain the changes that it will necessitate, because there will be an enormous political push against the idea, led by the insurers and the drug companies and all the rest of the usual suspects. Single-payer needs to be debated in real-world terms, and not just the abstract. Single-payer proponents should welcome this debate, if they have the courage of their convictions. But they better be ready to forcefully defend all aspects of the idea, because while the attacks probably won’t be coming from a Democratic presidential frontrunner next time around, they will be coming nonetheless. Hopefully, Bernie’s bill will provide the rhetorical ammunition for single-payer proponents to successfully repel such attacks.

Chris Weigant blogs at ChrisWeigant.com Follow Chris on Twitter: @ChrisWeigant

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