The U.S. health-care law known as Obamacare turns 10 next year but still finds itself at existential risk both politically and legally.
Millions of Americans owe their health coverage to the law enacted under President Barack Obama and fellow Democrats, even as opponents have trimmed its scope. It remains a target for elimination by the Republican Party and Obama’s successor, President Donald Trump, who calls it “really bad health care.” A legal challenge calling the law unconstitutional is the latest threat.
1. How much of Obamacare still exists?
Most of it, including tax subsidies to help people afford coverage and,...