You’ve heard of the undeserving poor? Get ready for the undeserving sick.

A top Trump administration official defended the American Health Care Act, the GOP bill to repeal the Affordable Care Act, by arguing Thursday that it would take care of people who have pre-existing conditions without asking healthy people to pay for those who made poor choices.

Mick Mulvaney, director of the Office of Management and Budget, made the comments during the LIGHT Forum at Stanford University in response to a question about the “Jimmy Kimmel test.” That was a reference to comedian and late-night host Jimmy Kimmel, who, after watching his newborn son struggle but survive a severe medical scare last week, declared, “No parent should ever have to decide if they can afford to save their child’s life.”

Although Kimmel went out of his way to avoid making a partisan point, his statement, which went viral almost immediately, was an obvious jab at the Republican health care bill, which would allow states to waive Obamacare rules that prohibit insurance companies from charging higher premiums to people with pre-existing conditions.

Republicans have frequently responded by pointing to AHCA provisions designed to help these people. High on the list is funding for special insurance plans, called high-risk pools, that would be available to people unable to get coverage at standard prices because of their medical histories.

“We have plenty of money to deal with that. We have plenty of money to provide that safety net so that if you get cancer you don’t end up broke,” Mulvaney said at the Leaders in Global Healthcare and Technology forum.

But then he drew a distinction between people like Kimmel’s son, born with a congenital heart disease, and people who end up with conditions like diabetes. “That doesn’t mean we should take care of the person who sits at home, eats poorly and gets diabetes,” Mulvaney said, according to a Washington Examiner account consistent with real-time social media reports. “Is that the same thing as Jimmy Kimmel’s kid? I don’t think that it is.”

OMB's Mulvaney says AHCA should meet Kimmel test - cover all kids - but not adults who make "bad choices" #LIGHTForum17 #KimmelTest — Lee Sanders, MD, MPH (@SandersMDMPH) May 11, 2017

It’s not the first time a Republican has said something along those lines. Rep. Mo Brooks (R-Ala.) made similar comments a few weeks ago, saying that the AHCA would benefit people who “have done the things to keep their bodies healthy … who have done things the right way.”

And it happens to be an intellectually honest expression of what many conservatives think ― namely, that it’s wrong to require higher insurance premiums for healthy people in order to pay for the costs of the sick, except in a very narrow class of cases.

But the “cross-subsidy” of healthy and sick that Mulvaney, Brooks and perhaps many other Republicans find objectionable is also the underlying principle of every universal coverage scheme in the world and the vast majority of employer plans here in the U.S. as well.

There are a few reasons for that.

One is that people are a lot less responsible for their own medical problems than the likes of Mulvaney and Brooks seem to think. Although the research on causes of medical problems is far from definitive, the rough consensus among experts is that behavior explains no more than half of all medical problems and probably a lot less.

Pretty much every condition that generates high medical bills has a substantial hereditary or environmental component, or both ― a point that the American Diabetes Association was quick to make Friday in response to Mulvaney.

“Mr. Mulvaney’s comments perpetuate the stigma that one chooses to have diabetes based on his/her lifestyle,” the ADA said. “All of the scientific evidence indicates that diabetes develops from a diverse set of risk factors, genetics being a primary cause.”

Another big reason most health insurance systems treat people equally regardless of medical condition is that segregating them almost inevitably leads to shabby care for the sick, regardless of how they got that way. High-risk pools are actually a perfect example of this. Roughly two-thirds of the states operated them before the Affordable Care Act took effect, and they inevitably offered coverage that was less affordable, less available or less comprehensive than standard policies.

Although those plans helped some people, offering them much-needed security, by and large they were an inadequate solution for people with medical problems who were often left with crippling bills and poor access to care, no matter how deserving or undeserving. Republicans have said their high-risk pools would work better under the AHCA because it allocates more money for them, but few experts think the money proposed is enough.

Forcing insurers to cover people with pre-existing conditions has made insurance more expensive and has caused some real hardship, particularly among those who don’t qualify for the Obamacare subsidies. But lawmakers could fix that by making the subsidies more generous and more widely available, or by taking other steps, such as using government bargaining power to drive down drug prices.

But those options are not on the table because they would require some combination of higher spending and taxes to pay for it, or more regulation. And so Republicans are proposing instead to undermine the Affordable Care Act’s protections for people with pre-existing conditions ― justifying it, every once in a while, by suggesting that the people who would end up struggling with medical bills have themselves to blame.