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We all know President Donald Trump is overhauling Obamacare in his own image, weakening the law after congressional Republicans failed to repeal it.

But what kind of insurance market is the White House building? It can be hard to separate what was already underway in the ACA before Trump came along from what the president is doing to undermine and change it.

So I conducted a time-travel experiment.

I asked 10 actuaries and policy experts to imagine what Obamacare's insurance markets will look like in 2020, assuming that the law is never repealed and Congress fails to stabilize it. In that scenario, we can safely say that the Trump administration will be primarily responsible for the law as it exists by then.

This is what I learned:

1) Obamacare already had some problems — but Trump will make them worse

The ACA had become, in practice, a way to insure lower-income Americans and to protect people against discrimination for their medical history. But the tradeoff was that insurance had become unaffordable or undesirable for the younger and healthier people asked to pay higher rates and for people who didn’t receive the law’s generous financial aid.

But Trump's changes to the law — allowing people to buy "short-term" health insurance that doesn't comply with the law's rules and weakening enforcement of the individual mandate — will make those trends worse when they could have been improved.

"This is just gonna accelerate where the ACA was slowly evolving to," Craig Garthwaite, a conservative health economist at Northwestern, told me.

Sick people and people who receive generous financial assistance are going to stay in Obamacare. The former group needs the law's robust coverage and the latter group still sees a good deal for the law's plans because the federal government.

But healthier people and people who receive no assistance will abscond from the non-ACA coverage, especially without fear of the mandate penalty. Trump will have created a bifurcated market, where sicker and poorer people stayed in Obamacare, and healthier, middle-class people exited.

"When you put your foot on the accelerator, you can get there a lot faster," Garthwaite said. "That’s what Trump is doing.

2) Whatever he does, Trump won't destroy Obamacare entirely

The president is clearly going to do his best to weaken the ACA and provide outlets for people to leave its markets. But the law's incentives should prove somewhat resilient to that sabotage.

People who receive generous financial assistance under the law should continue to see good deals for their coverage. They will be protected from any dramatic premium hikes resulting from Trump's actions.

As we saw this year, plans and state insurance commissioners were able to respond to the administration ending the cost-sharing reduction payments in a way that led to many subsidized consumers getting lower prices on more robust plans.

"The people who are buying on the market will be seeing better deals if they’re receiving subsidies," David Anderson at Duke University said.

For the same reason, health insurers probably won't exit the ACA markets en masse. They know they can price their plans as high as they like, and these subsidized customers will be protected. The federal taxpayer will pick up the tab instead.

That should provide a strong incentive for at least one health insurer to operate everywhere. We shouldn't see a pandemic of bare counties.

"It’s tough to deal with an unreliable partner. However, on mechanical grounds, they know how to price risks, they know how to price a bad market," Anderson said. "Given the subsidy structure of the ACA, there is a very strong incentive for every county to have at least one insurer."

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3) The people who will be most hurt: older, middle-class Americans

Obamacare rates will rise, thanks to Trump. We've already seen it this year. But health insurers will stay in the market because they can set premiums as high as they like.

People receiving subsidies will stay because they're still seeing good deals. They won't actually feel those higher rates.

Healthier, middle-class people will leave (which will drive rates ever higher) because Trump will have made skimpier, but cheaper, non-Obamacare coverage more readily available. They also won't have to fear the mandate.

But that leaves one group who is really at risk in this scenario: older, middle-class Americans who need real health insurance but don't qualify for federal assistance.

The older you are, the more likely you are to have chronic conditions that require regular medical attention or that you'll have an unexpected diagnosis. These are not the people who will find the skimpier non-ACA coverage attractive.

But if, at the same time, you make too much money to qualify for Obamacare's aid, you will have to pay the full price of the premiums for ACA coverage, prices that Trump's actions will likely drive higher in the next few years.

So you’ll be left to choose between paying rising premiums on the ACA markets or taking your chances with the cheaper but less comprehensive coverage that Trump brought back.

Several people made this observation in my interviews: These older, middle-class people — the people most at risk — tend to be Trump voters.

"The trend is going to be: Trump’s people get hurt," Jon Kingsdale, who ran the Massachusetts market that Obamacare was based on, told me.

Chart of the Day

Obamacare 2020. This is maybe the simplest way to think about how Trump is going to change the insurance market. About 15 million people buy ACA-compliant coverage right now.

Over time, as rates rise and Trump opens up more routes to non-ACA coverage, we would expect the people who receive the law's subsides (about 8.7 million) to stick around. But the 6.7 million who don't receive assistance are the ones likely to exit, as premiums become unaffordable. The only nonsubsidized people likely to stay are the ones who most need the robust ACA coverage.

Kliff’s Notes

Your daily top health care reads, with research help from Caitlin Davis

News of the day

“Confusion clouds open enrollment with Republicans still eager to dismantle Obamacare”: “Obamacare is about to have its worst open-enrollment season ever — and that’s no accident.President Donald Trump and Republicans in Congress still aim to dismantle the 2010 law. Making it look bad helps their cause, even as they’ve failed repeatedly to repeal or replace Obamacare.” —Paul Demko, Rachana Pradhan, and Adam Cancryn, Politico

“Obamacare is about to have its worst open-enrollment season ever — and that’s no accident.President Donald Trump and Republicans in Congress still aim to dismantle the 2010 law. Making it look bad helps their cause, even as they’ve failed repeatedly to repeal or replace Obamacare.” —Paul Demko, Rachana Pradhan, and Adam Cancryn, Politico “With the wallet empty for KidsCare, Ducey quietly pushes for funding for children's health”: “Arizona's KidsCare account is running on fumes. Boosted by an extra $22 million in leftover federal money, the program is still on track to run out of money by late November. That would force the state to kick more than 23,000 kids off the program. That move could cost Arizona even more, as reliable health care is often seen as one safety net to keep children out of the state's foster-care system.” -—Mary Jo Pitzl, Arizona Republic

“Arizona's KidsCare account is running on fumes. Boosted by an extra $22 million in leftover federal money, the program is still on track to run out of money by late November. That would force the state to kick more than 23,000 kids off the program. That move could cost Arizona even more, as reliable health care is often seen as one safety net to keep children out of the state's foster-care system.” -—Mary Jo Pitzl, Arizona Republic “The Governor Blocked Medicaid Expansion. Now Maine Voters Could Overrule Him.”: “The referendum on Nov. 7 represents a new front in the pitched political battles over health care. Maine is one of 19 states whose Republican governors or legislatures have refused to expand Medicaid under Obamacare, and the other holdouts — particularly Utah and Idaho, where newly formed committees are working to get a Medicaid expansion question on next year’s ballot — are closely watching the initiative.” —Abby Goodnough, New York Times

​Analysis and longer reads

“An Iowa Teenager Didn’t Wreck His State’s Health Care Market. Here’s Who Did.”: “The law has worked well in other parts of the country. And if its design can explain some of Iowa’s problems, it cannot explain all of them. Experts are in wide agreement that the state’s insurance market would be in better shape, with more carriers and more affordable options, if not for a series of crucial decisions at the state and federal level ― and at Wellmark, as well.” —Jonathan Cohn, Huffington Post

“The law has worked well in other parts of the country. And if its design can explain some of Iowa’s problems, it cannot explain all of them. Experts are in wide agreement that the state’s insurance market would be in better shape, with more carriers and more affordable options, if not for a series of crucial decisions at the state and federal level ― and at Wellmark, as well.” —Jonathan Cohn, Huffington Post “Trump and the Essential Health Benefits”: “If the rule is adopted, each state can pick whatever essential health benefits it likes. No longer will it be choosing from a preselected menu; it’ll be picking the essential benefits out of a hat. In so doing, the proposed rule looks like it would unlawfully cede to the states the power to establish the essential benefits.” —Nicholas Bagley, Incidental Economist

“If the rule is adopted, each state can pick whatever essential health benefits it likes. No longer will it be choosing from a preselected menu; it’ll be picking the essential benefits out of a hat. In so doing, the proposed rule looks like it would unlawfully cede to the states the power to establish the essential benefits.” —Nicholas Bagley, Incidental Economist “CVS bid for Aetna: A $66 billion bet on cutting drug costs”: “The proposed merger between U.S. pharmacy operator CVS Health Corp and No. 3 health insurer Aetna Inc represents a $66 billion bet that insurers can drive down high U.S. drug prices by cutting out the middleman. The move is the most expensive effort to date that would enable a national health insurer to take back full control of prescription medicines for their customers by negotiating prices with pharmaceutical manufacturers and setting customer out-of-pocket costs for each drug.” —Caroline Humer and Carl O’Donnell, Reuters

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