Former Vice President Joe Biden has made it clear that he doesn’t believe Medicare-for-all would work, a policy stance that sets him apart from much of the 2020 field.

From recent comments, however, it’s not entirely clear he knows what the legislation to enact Medicare-for-all — a proposal popularized by Sen. Bernie Sanders (I-VT) that’s been co-sponsored by several 2020 presidential candidates including Sens. Elizabeth Warren (D-MA), Kirsten Gillibrand (D-NY), Kamala Harris (D-CA), and Cory Booker (D-NJ) — would actually do while moving Americans from private to government health insurance.

“What happens to Obamacare?” Biden asked reporters in Detroit earlier this week. “Maybe they have a plan. I haven’t seen it.”

He also asked a series of leading questions about Medicare-for-all. Here are his comments in full, as transcribed by the Washington Post’s Dave Weigel:

But you know let’s not play a game. You cannot keep Obamacare. And by the way, don’t you find it interesting — that’s a rhetorical question — don’t you think it’s interesting, the idea that everybody acknowledges it’s going to take a while to pass this? Number one. And number two, once it’s passed they’re saying it’s four years implementation. Now, that kind of in and of itself says this could be kind of hard to do. What happens in the meantime? What happens to Obamacare? What happens to those people, one hundred million people covered by it? Maybe they have a plan. I haven’t seen it. How are they going to fund that? What are they going to do? What are they going to do for the situation that you have people with preexisting conditions and 20 million people who got coverage?

There are a few misleading things here: People with preexisting conditions would not lose coverage under Medicare-for-all, and the Affordable Care Act has covered closer to 20 million people, not 100 million. Nearly 8.5 million people enrolled in a health plan on the Obamacare marketplace for 2019, and roughly 13 million have gained coverage through Medicaid expansion. Biden’s campaign clarified that he was referring to 100 million people with pre-existing conditions who might have struggled to get insurance before Obamacare. Medicare-for-all would not exclude anyone based on preexisting conditions.

Biden has his own health care plan to build a public option into Obamacare. This would still be a significant leftward shift in the American health care system, but it wouldn’t guarantee coverage to everyone.

His comments, though, nod to a major obstacle for Medicare-for-all advocates: There’s a lot of confusion around what a single-payer health care system actually means and how the United States would get there. Even Rep. Seth Moulton (D-MA) got single-payer health care confused with the fully socialized system veterans currently use.

The health care debate around the brand of Medicare-for-all has become divorced from the actual policy proposal. That said, there is actual legislation out there, proposed by Sanders, that answers some of the questions Biden has posed.

Democratic presidential candidate former Vice President Joe Biden speaks during the AARP and Des Moines Register Iowa Presidential Candidate Forum.

Justin Sullivan/Getty Images

Joe Biden’s Medicare-for-all questions, answered

The thrust of Biden’s comments is that Medicare-for-all would be hard to achieve. That’s absolutely true. Any leftward shift on health care — including Biden’s proposal — would likely require Democrats to wield big majorities the House, the Senate, and the White House to reach consensus. Enacting single-payer would require broad Democratic consensus, which doesn’t exist right now. That doesn’t make it impossible, as Sarah Kliff wrote for Vox; in 1962, Canada overcame thousands of doctors going on strike to come to love its single-payer program.

But in making that argument, Biden seems to be raising other leading questions — many of which have answers.

“What happens in the meantime?”

The current Medicare-for-all proposal, as introduced by Sanders, eliminates insurance through employers or bought individually and moves all Americans to Medicare, which would cover their health care costs with no premiums, no copay, and no deductible.

That’s a major change to the health care system, and it has a four-year transition period — a part of the proposal written by Gillibrand that gradually expands Medicare to Americans by age, starting with children and adults between 55 and 65 and making Medicare available to everyone in the fourth year.

In the first year, the plan would establish a public option — called the Medicare Transition Plan — equivalent to the best insurance option on the Obamacare exchanges, which covers about 90 percent of medical costs. It would also lower the eligibility age for Medicare to 55, from the current 65. The following year, that age eligibility would be lowered to 45, then to 35, and then, in year four, everyone would be transitioned over.

“What happens to Obamacare? What happens to those people, 100 million people covered by it?”

If Medicare-for-all were to be enacted, it would replace Obamacare, which expanded coverage through private insurance (which the proposal would eliminate) and Medicaid (which would be replaced with Medicare).

Obamacare has been successful in getting millions of people health insurance — roughly 20 million people have been covered by the program, a combination of those enrolled in the exchanges and those covered by expanded Medicaid. Single-payer would cover everyone, including the roughly 100 million people with preexisting conditions.

In Sanders’s Medicare-for-all, those people covered by the exchanges and Medicaid during the transition would retain coverage through the Medicare Transition Plan.

“How are they going to fund that?”

The biggest criticism of Medicare-for-all is its cost — and Biden isn’t the only one with this question, which hasn’t been thoroughly answered by the existing plans.

Federal spending would have to increase $32 trillion over 10 years to support Medicare-for-all, the latest price figure from libertarian-leaning Mercatus Center at George Mason University (the left-leaning Urban Institute came up with that same figure in 2016). As Vox’s Dylan Scott pointed out, that’s actually a reduction in the total amount spent on health care in America. Some features, including the lack of cost sharing, might encourage Americans to use health services more than they already do.

Sanders’s office released a list of possible ways to cover the program, including taxes targeting the wealthiest Americans and Wall Street. But those measures on their own would not raise enough. This means taxes would go up for individuals. Sanders argues that individuals would likely be paying less on net because they would not have premiums, deductibles, or copays with their health services, and prescription drug costs would be capped at $200 annually.

Biden’s plan would cost the federal government significantly less and mean smaller tax increases, but would leave more to the enrollees — like premiums, copays, and the like. And it’s true that Sanders’s plan hasn’t gotten specific about how, exactly, it would pay for the costs, though they have proposals.

“What are they going to do for the situation that you have people with preexisting conditions?”

Medicare-for-all covers everyone, with or without preexisting conditions. Medicare-for-all would expand Medicare coverage to also include dental, vision, hearing, and some prescription medication.

The difference between Biden’s and Sanders’s health care plans comes down to private insurance

Sen. Bernie Sanders (I-VT) speaks while introducing health care legislation titled the “Medicare for All Act of 2019.”

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As I explained after Sanders’s major 2020 campaign speech about Medicare-for-all, fundamentally, Sanders wants to challenge the leading technocratic approach to health care by posing a basic question about a moral problem: Can a health care system in which private insurance plays a significant role incentivize giving sick people care? Sanders says no.

Biden disagrees. His proposal would still significantly push the current health care system to the left by establishing a public option and aggressively tackling drug prices. Biden’s plan said this public option will reduce costs by “negotiating lower prices from hospitals and other health care providers” — essentially using the same bargaining power that Medicare currently has.

As Vox’s Matt Yglesias explained, that would make the public option look very attractive to a lot of people compared to the private plans. Biden’s plan would also make the Affordable Care Act’s tax credits more generous and introduce measures to reduce drug prices — like allowing the government to negotiate prices and allowing people to buy FDA-approved drugs from overseas.

But it would retain private insurance, avoiding a consistent attack on the Senate single-payer plan: the fact that all Americans with private insurance would have to switch to the public program.

Biden’s plan could be seen as a significant stepping stone toward single-payer. Sanders says that’s not enough.