On day one of his presidency, Donald Trump asked Congress to repeal The Affordable Care Act (ACA). While the issue has taken a back seat to his more recent immigration ban, and no definitive action has been taken on removing and replacing the health care legislation, the new administration’s request has caused considerable controversy, alarm, and protest in many quarters.

There are local implications. Some 800,000 New Jersey residents have purchased health insurance under the act. In Princeton’s two zip codes, 1,696 people signed up.

“Out of that number, 947 of them got a federal subsidy to make it more affordable, at an average of $377 a month,” said Heather Howard, a member of Princeton’s governing body and a lecturer in public affairs at Princeton University’s Woodrow Wilson School of Public and International Affairs. Ms. Howard is also a faculty affiliate at the Center for Health and Wellbeing and the director of two programs funded by the Robert Wood Johnson Foundation: Advancing Coverage in States, and the State Health and Value Strategies Program. Previously, she was New Jersey’s commissioner of health and senior services.

“So just in our zip codes,” she continued, “you’ve got 1,700 people who had access who might not have it otherwise, and 1,000 who got a federal subsidy to make it more affordable. All of that could go.”

Many questions remain about the future of health care in this country. “We’re hearing that the plan is to repeal the Affordable Care Act but we don’t know a lot about the replacement plan, and that’s significant,” said Kerry McKean Kelly, vice president for communications at the not-for-profit New Jersey Hospital Association. “If we don’t have a comparable plan, there are close to 800,000 newly insured New Jerseyans who could be at risk.”

The ACA covers more than 20 million people who were previously uninsured. But it is not all-pervasive through the United States health system. “Obamacare is just a smallish, complicated and somewhat ugly patch onto a hugely complicated and hugely ugly health care financing system,” said Uwe Reinhardt, the James Madison Professor of Political Economy at the Wilson school. Mr. Reinhardt, who offered comments in a post-election article published by the University November 16, is also a past president of the Association of Health Services Research and was commissioner on the Physician Payment Review Committee.

He added, “My hunch (or advice to Donald Trump) is to make a big brouhaha of seeming to repeal Obamacare (to keep a campaign promise), but in fact to keep many of its features that work or could be made to work better and rechristen it to something like TrumpCare, or FreedomCare, or something like that. No one would be the wiser.”

The future without the ACA also affects hospitals. “There is a lot of worry, because health care providers took significant cuts under the ACA,” Ms. Kelly said. “Hospitals alone in New Jersey absorbed about $1.5 billion under the first eight years of the ACA. If those cuts remain and we’ve lost the newly insured individuals we’ve been caring for, that is a significant hole hospitals will be facing. They’d have to make some really tough choices about how they provide care.”

While there is no immediate, practical impact, President Trump’s request “sends a clear and strong signal of the intention of the administration,” said Ms. Howard. “The ACA isn’t perfect and costs were too expensive and growing. But all the proposals out there now will have the impact of raising prices for consumers. Estimates are that up to 30 million nationally would become uninsured. Insurance companies may withdraw from the market. There will be a lot of volatility. We’re in a period of great uncertainty and that’s scary for families.”