Are you looking for some Democratic infighting over relatively modest disagreements in health-care policy? Well, today is your lucky day.

Sen. Kamala D. Harris (D-Calif.) has now unveiled her health-care plan, and after some uncertain answers to questions about what place private insurance would have in her vision, she has put together something that seems to take a path between Bernie Sanders’s fully single-payer idea and Joe Biden’s plan.

In a way, Harris’s idea is the truest expression of Medicare-for-all because it would universalize something like Medicare as it exists today — even some of the parts that single payer advocates such as Sanders don’t like.

So naturally, the knives are out. Biden’s campaign released a statement accusing Harris of flip-flopping on the question of a future role for insurance companies and calling it a “have-it-every-which-way approach.” Sanders’s campaign manager tweeted, “So continues her gradual backdown from Medicare For All. This is why you want a candidate with a lifetime of consistency and a track record on the big issues facing us.”

Are the differences between them really that large? Let’s look at what Harris is proposing.

“Medicare works,” Harris says in her plan. “Now, let’s expand it to all Americans and give everyone access to comprehensive health care.” But what she’s offering represents an expansion of Medicare in its current form, not Medicare in a more fully public form, in one critical way: the role of private insurers.

This is something many people may not understand as they watch this debate. The most prominent advocate of Medicare-for-all, Sanders, is actually proposing something that departs from Medicare in important ways. He would offer substantially more benefits than Medicare now does, including vision and dental care, and do it with zero cost-sharing (copays, deductibles), which is also not true of Medicare.

And critically, right now about a third of seniors choose Medicare Advantage plans in which a private insurer administers their Medicare (Medicare Advantage plans usually offer benefits not available in traditional Medicare). These plans would eventually disappear under Sanders’s system. But they are an important part of Harris’s plan. Here are the basics of what she would do:

  • Immediately open up Medicare to anyone who wants to buy in
  • Automatically enroll the uninsured and newborns in the new system, which would include expanded benefits such as dental and vision
  • Transition over 10 years to a newly expanded Medicare system for everyone, including everyone who now has employer-sponsored insurance
  • Allow private insurers to do what they do now with Medicare Advantage, offering plans that adhere to (enhanced) Medicare requirements
  • Pay for it with taxes on Wall Street, including a financial transactions tax

As Jonathan Cohn notes, while some plans like Biden’s maintain the private system but offer a public option for those who want it, Harris is essentially moving to a public system but offering a private option for those who want it.

So this really is a middle way between the public option advocates and the single-payer advocates. My read on the reaction so far is that the criticism from the center is about Harris’s sincerity less than the substance, while the criticism from the left is all about the fact that private insurers would get to stay in the system, milking it for profits at the expense of the public.

I’ve long held that sincerity is irrelevant in a case like this. Now that Harris has proposed this idea, it’ll be the starting point for reform if she becomes president, no matter how long it took her to arrive at it. Candidates keep big promises like this one. We should also keep in mind that any proposal will be run through a long and arduous legislative process, and what comes out on the other end will not be in exactly the form it was during the campaign. Which is why the granular details are less important than the basic approach.

As for the political question, it’s hard to tell whether allowing Medicare Advantage-like plans would quiet the fears of those who hear “under Medicare-for-all private insurance will be eliminated” and grow uneasy about the change. What we can say for sure is that insurance companies will fight any major reform just as hard as they will fight single-payer.

Nevertheless, the distinctions between the plans are important (and a number of candidates, including Elizabeth Warren, haven’t yet released theirs). But Harris has done something important: laid out a proposal different from what has been offered by any other candidate so far. Now she has to make a case for it.