Within days, the Supreme Court is expected to decide the fate of the Affordable Care Act.
If the court determines that Congress acted within its constitutional powers in passing President Barack Obama's landmark health care reform bill in March 2010, the gradual overhaul of America's health insurance system will continue.
But what if the Supreme Court strikes down the law, in whole or in part?
That's a big "what if," given the measure's size and scope, and the fact that many of its provisions have already taken effect.
"While 'chaos' might be a bit strong, it would create a lot of uncertainty because basically we would go back to square one where we were three or more years ago in recognizing that our health care system is broken -- but not knowing exactly how to fix it," says Dr. Glen Stream, president of the American Academy of Family Physicians.
Here's how American health care might be shaken up if the Supreme Court strikes down the Affordable Care Act.
It's all about the 'individual mandate'
The cornerstone of the Affordable Care Act -- and the focus of the Supreme Court challenge by 26 states and the National Federation of Independent Business -- is its "individual mandate" clause, which requires Americans to buy health insurance if they don't have it. If the court rules that Congress overstepped its powers with the individual mandate, it could throw out only that part of the law, or it could toss out the Affordable Care Act completely.
The individual mandate, which is expected to add 30 million of America's approximately 50 million uninsured to the health insurance pool beginning in 2014, is considered essential to making the "guaranteed issue" clause work. That provision ensures that people with pre-existing conditions have access to coverage; it's the concession the law requires insurers to make in exchange for millions of new customers.
"They're two sides to the same coin," says Jessica Arons, director of the Women's Health and Rights Program at the Center for American Progress, a nonpartisan educational institute. "If they were to strike down the individual mandate, I think guaranteed issue unfortunately would go away."
Other reforms already in effect that could face a similar uncertain future include the following.
- The law's elimination of lifetime and annual limits on health insurance benefits.
- Its discount on name-brand drugs for seniors, to close the Medicare "doughnut hole."
- The expanded coverage for young adults to age 26 under a parent's plan.
- Customer rebates from insurers that spend too much on administrative costs and bonuses.
- Tax credits to 4 million small businesses to help them insure their employees.
- Expansion of Medicaid so states can insure more low-income residents.
The business case for preventive services
Some parts of the law appear to be here to stay, regardless of what the court does. For example, its elimination of copays and deductibles for preventive services such as mammograms, colonoscopies and well-baby visits may survive, at least on employer plans, which insure 3 out of 5 working Americans younger than 65.