After the so-called “skinny” repeal of the Affordable Care Act failed to pass in a Senate vote early Friday morning, President Donald Trump tweeted out his thoughts on the subject.

“As I said from the beginning, let ObamaCare implode, then deal. Watch!” he said.

It won’t necessarily happen by itself. The Affordable Care Act, also called Obamacare, has been plagued by high-profile health insurer exits and rising premiums. But that doesn’t tell the whole story. Some health insurers are turning a profit on the exchanges, like Centene Corp CNC, -2.94% , which is expanding its presence. And the Congressional Budget Office said in March that the individual market would likely be stable in most areas under current law.

There are a few ways Trump can help implosion occur. He’s most likely to do so through cost-sharing reduction payments, which pay back health insurers for the increased cost of certain plans on the ACA’s marketplaces.

“If ObamaCare is hurting people, & it is, why shouldn’t it hurt the insurance companies,” Trump said in a Monday tweet in which he appeared to allude to the cost-sharing payments.

See our previous coverage of this issue:What Trump can do to undermine Obamacare, now that the GOP health bill has failed

Trump threatened to withhold cost-sharing payments this past spring as a negotiating tactic with Congressional Democrats. Without them, health insurers might stop offering plans, causing consumers to lose health insurance, according to The Commonwealth Fund, a health-care foundation.

That “could immediately destabilize the exchanges, perhaps fatally,” said Spencer Perlman, director of health-care research at Veda Partners, an investment advisor and consultancy.

Will GOP Have More Success With Taxes Than Health Care?

Trump could withhold the payments in August, said Height Securities analyst Stefanie Miller, “before Congress will be in a position to take that authority away from Trump legislatively.” (Congress has an extended recess coming up.)

The Trump administration could either end an appeal of a lawsuit over the cost-sharing payments on Aug. 20 or just decide not to make the payments, which are scheduled for Aug. 21, Perlman said.

Related: Trump aims to squeeze Democrats into health-care negotiations

There are also other ways to sabotage the health care law, which is administered by the Department of Health and Human Services, led by Secretary Tom Price.

Enrollment in the ACA’s exchanges is one key measure of the health law’s success. But enrollment appears highly dependent on marketing and promotion of the exchanges, making it an easy target for the administration.

Read more: ‘Skinny’ repeal of Obamacare fails to pass in late-night Senate vote

For example, enrollment for 2017 exchange plans looked like it was on track to surpass previous years until, under Trump’s administration, it dropped off.

“The secretary certainly can undermine the functioning of the ACA by refusing to encourage enrollment,” Veda’s Perlman said. But it’ll be difficult for Price to change exchange plan requirements, since “Price’s ability to alter the ACA’s insurance rules via the regulatory process is actually quite limited.”

But it’s likely that Congress will have to tackle market stabilization next, both Perlman and Miller said, probably when members return to work in September.

Bipartisan cooperation will be necessary, though, and “we do not expect Republicans and Democrats to reach a compromise quickly, meaning that uncertainty is likely to continue to plague the exchanges over the coming weeks and months,” Perlman said.

That also means Medicaid and Medicaid expansion are “safe for now,” he said, though hospitals — expected to be hit hard by ACA repeal — should keep facing challenges.

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