President Trump on Dec. 20 said that by passing the GOP tax bill, Republicans "essentially repealed Obamacare because we got rid of the individual mandate, which was terrible." (Reuters)

In the throes of his superlative-filled praise of the Republicans' tax bill, President Trump said this Wednesday: “We essentially repealed Obamacare.”

It is not true — and it could also have been a major political blunder for Trump and Republicans.

Republicans did pass a tax bill Wednesday that undoes one of the central components of Obamacare: the mandate that people have health insurance, or pay a fine.

Health-care experts say that does not mean Obamacare is dead. It is just in trouble — and by extension, so are the health-insurance markets that have framed their business model around the law. That means Trump may have opened up his party — and himself — for taking responsibility for whatever trouble lies ahead for the markets.

The only thing that can repeal Obamacare is legislation repealing Obamacare. Republicans tried to repeal parts of Obamacare this summer. They fell short by one vote.

Obamacare is severely weakened after Trump and congressional Republicans chipped away at it.

People can still enroll in health insurance using the state and federal marketplaces Obamacare set up. Enrollment is down in the first year of Trump's presidency, but it is “still respectable,” despite the Trump administration slashing the budget for enrollment outreach, said Alice Rivlin, a health policy expert at Brookings Institution.

After Trump signs the tax bill into law, enrollment could drop precipitously now that people are not financially pressured to buy health insurance. Health policy experts predict a sizable number of healthy people likely won't enroll.

President Trump's health-care actions could have ripple effects throughout the Affordable Care Act's marketplaces. (Jenny Starrs/The Washington Post)

That could two do things, say health-care experts: Drive enrollment down further and raise premiums even higher, since insurance companies will be spending more money on sick people without balancing it with healthy people.

That means that in places where there aren't wide swaths of insured Americans — such as rural areas in Iowa or New Hampshire — insurance companies could have incentive to pull out of Obamacare exchanges, further weakening the law. In a sense, Republicans are creating a self-fulfilling prophecy.

Some health experts warn it could be a prophecy Republicans could come to regret, since residents of less-populated areas and the self-employed, who are also often uninsured, tend to be Republican.

“Republicans are so eager to damage Obamacare that they are hurting their own constituents,” warned Paul Ginsburg, a health policy expert and director of the USC Brookings-Schaeffer Initiative.

Another crux of Obamacare, a greatly expanded Medicaid program, is still in place. (Republican attempts to slash Obamacare failed in large part because moderate GOP lawmakers were not willing to roll back Medicaid in their states.) That means a sizable number of low-income people who get their health insurance subsidized still will.

Trump unilaterally ended the part of the law that helps a significant number of people who are not on Medicaid.

In October, he abruptly ended federal subsidies for insurance companies that help lower-income people and people with extraordinarily high medical expenses pay for their costs. A bipartisan group of senators were trying to restore these cost-sharing subsidies in an effort to keep premiums level, but a deal to vote on the issue fell through Wednesday after the tax bill passed.

In short: Republicans have not succeeded in ending Obamacare. But they have damaged major pieces of it. That will likely translate to spiking premiums in rural areas and for low-income people. It also means those same people could have less choices for health insurance.

Without a plan to replace any of that, health insurance costs could continue to spiral upward.

“There's no one easy way to revive the health insurance market,” said Gary Claxton, a health policy expert at the Kaiser Family Foundation.

Yet, on Wednesday, Trump claimed all of this as a political victory. As The Fix's Aaron Blake touches on, that may be a statement the president and Republicans come to regret.