The three days of arguments before the Supreme Court may mark a turning point in a century of debate over what role the government should play in helping all Americans afford medical care. From the AP, a look at the issue through the years.
Former President Theodore Roosevelt champions national health insurance as he tries to ride his progressive Bull Moose Party back to the White House. It's an idea ahead of its time. Health insurance is a rarity and medical fees are relatively low because doctors cannot do much for most patients. But medical breakthroughs are beginning to revolutionize hospitals and drive up costs. Roosevelt loses the race.
Americans struggle to pay for medical care amid the Great Depression. President Franklin D. Roosevelt favors creating national health insurance, but decides to push for Social Security first. He never gets the health program passed.
Roosevelt establishes wage and price controls as part of the nation's emergency response to World War II. Businesses can't attract workers with higher pay so instead they compete through added benefits, including health insurance, which unexpectedly grows into a workplace perk. Workplace plans get a boost the following year when the government says it won't tax employers' contributions to employee health insurance.
Saying medical care is a right of all Americans, President Harry Truman calls on Congress to create a national insurance program for those who pay voluntary fees. The American Medical Association denounces the idea as "socialized medicine." Truman tries for years but can't get it passed.
Medicare for people age 65 and older and Medicaid for the poor signed into law. President Lyndon B. Johnson's legendary arm-twisting and a Congress dominated by his fellow Democrats succeeded in creating the kind of landmark health care programs that eluded his predecessors.
Sen. Edward M. Kennedy, D-Mass., offers his proposal for a government-run plan to be financed through payroll taxes.
President Richard Nixon puts forth a plan to cover all Americans through private insurers. Employers would be required to cover their workers and federal subsidies would help others buy insurance. The Watergate scandal intervenes.
Jimmy Carter pushes a mandatory national health plan, but a deep economic recession helps push it aside.
Congress passes and President Ronald Reagan signs into law COBRA, a requirement that employers let former workers stay on the company health care plan for 18 months after leaving a job, with the worker bearing the cost.
Helping the uninsured becomes a big issue of the Democratic primaries and spills over into the general election. Democrat Bill Clinton wants to require businesses to provide insurance to their employees, with the government helping everyone else; Republican President George H.W. Bush proposes tax breaks to make it easier to afford insurance.
Newly elected, Clinton puts first lady Hillary Rodham Clinton in charge of developing what becomes a 1,300-page plan for universal coverage. It requires businesses to cover their workers and mandates that everyone have insurance. The plan meets strong Republican opposition, divides congressional Democrats and comes under a firestorm of lobbying from businesses and the health care industry. It never gets to a vote in the Democrat-led Senate.
Hillary Rodham Clinton makes a sweeping health care plan, including a requirement that everyone have coverage, central to her bid for the Democratic presidential nomination. She loses to Barack Obama, who promotes his own less comprehensive plan.
Congress passes the Patient Protection and Affordable Care Act, designed to extend health care coverage to more than 30 million uninsured people. Obama signs it into law March 23.
After agreeing to hear a case determining the constitutionality of the Affordable Care Act in November 2011, there were three days of oral arguments before the Supreme Court on March 26, 2012.
The Supreme Court rules that the Affordable Care Act was constitutional. Supporters of President Barack Obama's health care law celebrated outside the Supreme Court in Washington after the court's ruling was announced.
Open enrollment for federal exchanges created by the Affordable Care Act on healthcare.gov officially began on Oct. 1, 2013. The website crashed within the first day, exposing a large number of problems. Two months later, on Dec. 1, 2013, the Obama administration declared that the site was running smoothly.