Donald Trump, pondering the problems with the American health care system, reportedly remarked to his aides at some point over the past two years: “Why can’t Medicare simply cover everybody?”

This would be maybe the biggest policy bombshell in Michael Wolff’s explosive new book, Fire and Fury — if we can believe it.

But the thing is, even though Trump would eventually oversee and endorse health care plans put forward by Republicans that would have led to tens of millions fewer people having health insurance, it is actually pretty easy to believe that he would be open to a universal, even government-funded program like Medicare-for-all.

It reminds us of the sharp contrast between the populist candidate that Trump claimed to be on the campaign trail and the pretty conventional Republican he has governed as. As a candidate, Trump wanted insurance for everybody. As president, he endorsed health care plans that would have led to 20 million fewer Americans having health insurance, compared to the health care law he so desperately wanted to repeal.

Wolff depicts a candidate and a president who is pretty disconnected from and disinterested in the policy particulars of health care reform, even though the pledge to “repeal and replace Obamacare” had been core to the Republican Party’s message for the past seven years.

“No one in the country, or on earth, has given less thought to health insurance than Donald,” former Fox News leader Roger Ailes reportedly said. When you remember that Trump has talked about health insurance as if it works like life insurance, that also isn’t so hard to believe.

But on the merits, Wolff writes, Trump was more inclined to support a universal, government-funded insurance program — more or less the Medicare-for-all plan that has been advanced by Bernie Sanders.

Below is the relevant passage from Wolff’s book:

All things considered, he probably preferred the notion of more people having health insurance than fewer people having it. He was even, when push came to shove, rather more for Obamacare than for repealing Obamacare. As well, he had made a set of rash Obama-like promises, going so far as to say that under a forthcoming Trumpcare plan (he had to be strongly discouraged from using this kind of rebranding — political wise men told him that this was one instance where he might not want to claim ownership with his name), no one would lose their health insurance, and that preexisting conditions would continue to be covered. In fact, he probably favored government-funded health care more than any other Republican. “Why can’t Medicare simply cover everybody?” he had impatiently wondered aloud during one discussion with aides, all of whom were careful not to react to this heresy.

At first, this might seem shocking: the most powerful Republican in the country endorsing, in essence, single-payer health care. But then you remember what Trump has said about health insurance and health care over the past year.

Back in January before he was sworn in, as the Obamacare repeal debate was getting underway, Trump was promising “insurance for everybody.”

“We’re going to have insurance for everybody,” he told the Washington Post. “There was a philosophy in some circles that if you can’t pay for it, you don’t get it. That’s not going to happen with us.”

People covered under the law, he said, “can expect to have great health care. It will be in a much simplified form. Much less expensive and much better.”

Insurance for everybody, a simpler system that’s much less expensive — you could argue that Medicare-for-all achieves those goals better than any of the plans the GOP put forward in the following year, which were projected to lead to as many as 24 million fewer Americans having health coverage, versus Obamacare. And remember, Trump would go on to call the House Republicans’ bill “mean.”

Of course, a Trump plan to expand Medicare never materialized, and it’s easy to divine why, if Wolff’s account is at all accurate: Trump doesn’t really understand health care or have the attention span for its minutiae — it is so complicated, after all.

The details of the contested legislation were, to him, particularly boring; his attention would begin wandering from the first words of a policy discussion. He would have been able to enumerate few of the particulars of Obamacare — other than expressing glee about the silly Obama pledge that everyone could keep his or her doctor — and he certainly could not make any kind of meaningful distinction, positive or negative, between the health care system before Obamacare and the one after.

Instead, according to Wolff, House Speaker Paul Ryan and Trump’s top adviser Steve Bannon steered him toward a more conventional repeal-and-replace plan, the kind that Republicans had been promised since the Affordable Care Act first passed. One meeting with Ryan and his eventual health secretary Tom Price seems to have been crucial:

It was Ryan who, with “repeal and replace,” obfuscated the issue and won over Trump. Repeal would satisfy the Republican bottom line, while replace would satisfy the otherwise off-the-cuff pledges that Trump had made on his own. (Pay no attention to the likelihood that what the president construed as repeal and replace might be very different from what Ryan construed as repeal and replace.) ... The two men summed up for Trump — who kept wandering off topic and trying to turn the conversation to golf — seven years of Republican legislative thinking about Obamacare and the Republican alternatives. Here was a perfect example of an essential Trump paradigm: he acceded to anyone who seemed to know more about any issue he didn’t care about, or simply one whose details he couldn’t bring himself to focus on closely. Great! he would say, punctuating every statement with a similar exclamation and regularly making an effort to jump from his chair. On the spot, Trump eagerly agreed to let Ryan run the health care bill and to make Price the Health and Human Services secretary.

But Wolff cogently identifies the disconnect between the populist Trump and the Trump who would endorse a plan that slashes Medicaid while repealing taxes on health insurers and pharmaceutical companies.

Bannon, the supposed author and vessel of Trumpian populism, was reportedly uncomfortable with the repeal-and-replace plans, at least in their particulars. He seemed acutely aware that even if Trump was obligated to support repealing the ACA because he was the leader of the Republican Party, its inevitable consequences would clash deeply with his promises to protect the working men and women of America.

But Bannon, seeing health care as a weak link in Bannonism-Trumpism’s appeal to the workingman, was careful to take a back seat in the debate. Later, he hardly even made an effort to rationalize how he’d washed his hands of the mess, saying just, “I hung back on health care because it’s not my thing.”

He wasn’t wrong.