CNN anchor Poppy Harlow exposed some major weaknesses in Bernie Sanders‘ “Medicare for All” plan by grilling the independent Vermont senator on his promise that Americans will be able to keep their doctors under his plan, and by getting him to brag that his staff’s private health insurance is “the best health care plan you can imagine.”

On Tuesday morning’s edition of CNN Newsroom With Poppy Harlow and Jim Sciutto, Harlow interviewed Sanders extensively on his Medicare for All plan, including a lengthy exchange in which she repeatedly pressed Sanders on his false claim that Americans will be able to keep the same doctors under M4A.

Harlow played a clip from a June 16 Fox News interview during which Sanders repeated the claim that his plan would allow “all of the American people to continue to go to the doctor that you want to go to.”

“I really like my doctor, and I’d like to keep going to her, but what if she decides, Senator, that a Medicare for All plan doesn’t pay her out enough, and she’s going to just take private patients, then I would have to pay out-of-pocket to go to her,” Harlow said, adding “And that’s okay for me, because I can afford to, but it’s not okay for most Americans.”

“Could they still keep their doctor if their doctor decided ‘These rates aren’t enough for me?'” she asked.

“That is not the way the system is going to work,” Sanders said, but then described the ways in which his plan expands the number of people covered, and the types of services covered, but not the number of providers who would participate. His only mention of private participation was to say that “almost all doctors are now in Medicare.”

“But I’m just asking you, the fact of the matter is that not all doctors take that, because they don’t all like the rates that they’re paid,” Harlow said, and again asked “So can you 100% guarantee to all Americans that their existing doctor would see them under this plan, and they would not have to pay, out of pocket, a private rate?”

“Well as you well know, right now, all Americans cannot go to the doctor that they want within their own insurance program,” Sanders began, but Harlow interrupted to press the point.

“And I hear you, and I think the system is broken, and it needs to be fixed some way. But you said earlier this summer that people could essentially keep their doctors and their hospitals, and I’m just wondering is that 100% true for every American?” she asked.

“Under Medicare for All, as I said on that show, every American will be able to go to the doctor they want because doctors will be in the Medicare for All single-payer program, as they are right now in the Medicare program,” Sanders replied.

That last clause is the dead giveaway because as Sanders acknowledged to Harlow in this interview, not every doctor is currently participating in Medicare. He is correct that “almost all doctors are now in Medicare” — more than 90 percent — but nothing in his bill would guarantee they’d remain, and it certainly doesn’t compel every doctor to participate.

The essence of Sanders’ promise may be mostly true, but the reality is that his claim is even less factually accurate than the one that earned then-President Barack Obama the “Lie of the Year” award in 2013. It’s a political problem that could easily be remedied simply by saying almost all Americans could keep their doctors.

But it’s a substantive problem, as well, because Sanders has not addressed how M4A would affect participation rates, and appears to assume they’ll stay exactly the same.

Later in the interview, Harlow asked Sanders about his campaign’s recent labor dispute with his unionized campaign workers, and as Sanders announced that the issue had been settled, he volunteered a boast that undermined Medicare for All in a couple of ways.

“So starting today, all of those workers that are salaried will make $42,000 a year, or the equivalent of $15 an hour?” Harlow asked, to which Sanders replied: “I believe it’s more than $15 an hour.”

“And also, by the way, has probably the best healthcare plan that you can imagine,” Sanders continued, adding “I believe we cover 100% of the healthcare costs of our workers.”

That last part is not true, the deal the union negotiated pays 100 percent of the premiums, and only for the lowest-paid workers. For higher earners, it pays 85 percent.

Superficially, what Sanders is saying — that the private health insurance his staffers get is “the best healthcare plan that you can imagine” — means, by definition, that Medicare for All is not “the best healthcare plan that you can imagine.”

But it also reveals a deeper flaw in Medicare for All. Sanders claims that Americans will gladly pay more in taxes to save on health insurance premiums and other out-of-pocket expenses.

People like Sanders’ staffers — who have negotiated great health care plans as part of their compensation — would have those plans replaced by M4A, would pay more in taxes, and would just lose the value of the compensation they had negotiated.

It’s likely that M4A would entail lower out-of-pocket costs and cover more than even the best private plans — since M4A covers pretty much everything — but Americans’ satisfaction with their current health plans is an obstacle that proponents of Medicare for All ignore at their peril.

Watch the interview above, via CNN.

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