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It has been 14 years since then-President Barack Obama signed the Affordable Care Act, with Vice President Joe Biden at his side. It was one of that administration’s crowning achievements — or, as Biden said in a famous hot mic moment, a “big fucking deal.”

On Saturday, Biden and Obama plan to mark the anniversary with a virtual campaign event, as part of a broader effort to put the law at the center of Biden’s presidential reelection campaign. The idea is to remind voters about what the Affordable Care Act has accomplished ― and what could happen to it if Donald Trump retakes the White House.

There is a lot to say on both counts.

Tens of millions of Americans now get health insurance through the Affordable Care Act, either via expanded state Medicaid programs that the ACA funds or subsidized private coverage that the ACA makes available. Together, those features have brought the proportion of Americans without health insurance to historic lows.

The law also introduced legal guarantees of coverage for people with preexisting conditions. Those matter because, back in the day, insurance companies could charge higher premiums to people with diabetes or a history of cancer ― or deny them insurance altogether. They could also sell policies that left out whole swaths of coverage, like maternity care or treatment for mental illness.

Now with Trump on the ballot again, those changes could be in jeopardy ― for reasons that are right out in plain view, but aren’t getting the close look they deserve.

Repeal And The Mythical Obamacare Alternative

When Trump ran for president in 2016, repealing the law was a central promise. Once he got into office, he and the Republicans in charge of Congress made it their top priority — and came darn close to succeeding.

Late last year, Trump said he wanted to try again. “The cost of Obamacare is out of control, plus, it’s not good Healthcare,” he posted on Truth Social in November. “I’m seriously looking at alternatives.”

A few days after that, Trump posted a follow-up: “I don’t want to terminate Obamacare, I want to REPLACE IT with MUCH BETTER HEALTHCARE. Obamacare Sucks!!!” Trump also vowed that he would deliver “much better Healthcare than Obamacare for the American people.”

Trump never specified how he’d deliver this “much better” health care, which shouldn’t be a surprise. He didn’t spell out a “much better” alternative when he was running for president in 2016 either.

Trump’s fellow Republicans are proceeding the same way. A new budget proposal from the Republican Study Committee, which represents the majority of House Republicans, includes key elements of repeal like deep cuts to Medicaid and a rollback of regulations on preexisting conditions.

The document promises to introduce a system of “personalized and affordable health care.” But like Trump, Republicans aren’t providing details about how, exactly, they intend to accomplish that.

Of course, there’s a reason Republican plans are always so vague.

Their basic goal on health care, as with the rest of their agenda, is to scale back government spending, taxes and regulations of private industry. That serves their interest in shrinking government — which, in their telling, leads to a more efficient, ultimately more humane health care system.

But there’s no escaping the basic math of health care, which is that lots of people can’t get insurance without public programs or financial assistance from government. That is why projections in 2017 consistently showed Republican repeal alternatives would cause the number of uninsured Americans to skyrocket — and why it’s safe to assume that repeal would have the same results now.

“Trade-offs are inevitable in health reform, like in any complex policy issues,” Larry Levitt, an executive vice president at the health care research organization KFF, told me Friday. “You can’t just magically produce better coverage at lower costs.”

As for rolling back the law’s robust protections for people with preexisting conditions, Sarah Lueck, vice president for health policy at left-leaning think tank Center on Budget and Policy Priorities, said that would “return [America] to a time when people’s health history determines whether they can have health insurance, how much they pay, or what benefits they can get.”

The Political Outlook For Health Care ― And Biden

Fear of those consequences was a big reason that repeal proved so unpopular in 2017. That fear would likely be even greater now, given that the program appears to be more popular than ever — and enrollment in the Affordable Care Act’s private plans is higher than it’s ever been before.

Plenty of Republican lawmakers certainly remember how repeal worked out for them at the ballot box last time. Public anger over the repeal effort was probably the single biggest reason that the GOP lost control of the House in 2018. In the elections two years after that, it was still a political albatross, for both incumbent GOP legislators and Trump himself.

But it’s easy to forget just how close that repeal effort came to succeeding, even though it was deeply unpopular. Legislation came up just one vote short in the Senate, after all.

It’s also easy to underestimate Trump’s desire to erase Obama’s signature accomplishment ― and to forget how willing fellow Republicans could be to follow him, as they would on any cause that Trump declares a priority.

And the specter of repeal is really just the leading edge of a broader attack on health care programs that many, quite possibly most, Republican legislators endorse ― and that threatens two of Biden’s key policy accomplishments.

One is an initiative that allows the federal government to negotiate directly with pharmaceutical companies over what Medicare pays for certain high-priced drugs. It became law as part of the Inflation Reduction Act, the sweeping climate and health care bill that Biden and the Democrats enacted in 2022.

The Republican Study Committee budget calls for rescinding that power, on the theory — as conservatives have long argued — that regulating drug prices will ultimately limit profits in ways that make it harder to raise the money necessary for the development of new treatments.

The other Biden legacy in jeopardy is additional financial assistance to people buying subsidized coverage through the Affordable Care Act. This has reduced the cost of coverage, in some cases by hundreds of dollars or even more than $1,000 a year, so that more people can get coverage and those who already have it can get more generous policies.

Biden and the Democrats first made this extra assistance available in 2021, as part of their COVID-19 pandemic relief efforts, and then extended it in 2022 ― again, in the Inflation Reduction Act. It’s still a temporary measure, though, and set to expire in 2025.

Neither Trump nor his fellow Republicans have had much to say about its future. But given their antipathy toward the Affordable Care Act, it seems unlikely that they’d be enthusiastic about it. And if the program isn’t extended, prices for coverage will go back up.

Even with that extra financial assistance in place, the health care system still has tons of problems. Large swaths of the population struggle to pay medical bills because they don’t have insurance, or the insurance they have isn’t adequate.

But presented with a choice between turning back the clock to what health care looked like before the reforms that Obama and Biden enacted, or keeping those policies in place, Americans have signaled repeatedly that they prefer the latter.

Now Obama, Biden and their allies want to make sure the public realizes that same choice is on the November ballot. They’re starting that work Saturday.