Rep. Donna Shalala (D-Fla.), who oversaw the creation of a national insurance program for children as President Bill Clinton’s health secretary after his more ambitious health reform effort collapsed, described the ACA as an “operational platform,” a foundation for moving to covering everyone.

Given the decade of rancor, there are no guarantees for Obamacare. The Supreme Court has just agreed to hear another case, backed by President Donald Trump, that could dismantle the whole law — including the popular parts like protecting preexisting conditions. And the GOP hasn’t given up its pledge to repeal and replace the Affordable Care Act, even if it has given up explaining how it might do so.

But the law appears more secure than in its early days. Polls show the ACA has recently hit record levels of support following the GOP’s failed drive to upend the entire law, elimination of the unpopular individual mandate penalty and the right’s new focus on torpedoing Medicare for All. The rush by numerous Obamacare-friendly states to reopen enrollment in the past week demonstrated the law's potential as a safety net in a time of a major health crisis.

A drive for further change could supercharge Medicare for All proposed by Sanders. Or it could take the shape of some kind of public option, a voluntary, government-run program that would compete with private insurers, or various proposals to boost insurance subsidies or allow people to buy in to government programs.

Either would be a political lift, given the health care industry’s organized opposition against an expanded role for government. Princeton historian Julian Zelizer notes that even health proposals deemed too “incremental” by progressives are always labeled “socialized medicine” by their foes.

“Medicare was incremental — and it was attacked as socialized medicine. Both the Clinton plan and the ACA were seen as incremental ... but were attacked as huge government takeovers,” he said. “I don’t think the incremental approach really stops the attacks.”

But all the other big entitlements were hard to enact — and eventually grew.

Social Security, which is now universal and almost universally popular, began as a program for industrial and commercial workers — just about half the labor force, according to Ed Berkowitz, a professor emeritus at George Washington University and historian of social welfare policy.

In addition, there was a five-year gap between when people started paying taxes into Social Security, in 1937, and when they started getting benefits back in 1942. “It was financed in a pretty unpopular way,” Berkowitz said.

In a story that may be familiar to anyone who has followed the travails of the ACA, Social Security faced legislative battles, political attacks and litigation before finally becoming a broadly popular American program. But gradually, more people got covered under a series of new laws and expansions. By the early 1950s, it was well on the path to being universal.

While Social Security grew, the fight for broader health coverage stagnated. President Franklin Roosevelt never pushed much for it, as he created much of what became the social safety net during the Depression. President Harry Truman did make a bid for national health insurance, and it roundly failed.

By 1965, the moment came for Medicare and Medicaid. Both were breakthroughs — and both were much smaller than they are today. Lawmakers kept expanding Medicare over the coming decades: coverage for the disabled and end-stage kidney disease in the 1970s, hospice care in the early 1980s and a prescription drug benefit in 2003. Along the way, an attempt to add catastrophic care was enacted and quickly became one of the few benefit expansions ever to be repealed, because beneficiaries who bore the cost rebelled. A private insurance alternative, Medicare Advantage, was initially championed by Republicans but now has broader support.

POLITICO Pulse The latest news in health care politics and policy. Sign Up Loading By signing up you agree to receive email newsletters or alerts from POLITICO. You can unsubscribe at any time. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Medicaid, which got far less attention back when it was enacted, has grown to cover millions of more people than Medicare — and could continue to rise if coronavirus pushes the country into recession. The program, initially tied to cash assistance, over the years added more low-income families, pregnant women, long-term care and poor adults through a still-incomplete state-based expansion under Obamacare.

As Medicaid began to be perceived as a health program, separated from its welfare-related roots, it became easier for policymakers to grow it, said Diane Rowland, who ran the Medicaid program at the Kaiser Family Foundation for many years.

“There was always some kind of societal need that we could document,” said Rowland. That led Congress to add coverage, for instance to pregnant women to prevent maternal deaths and boost prenatal care.

And in 1996, the Children’s Health Insurance Program was created for the working poor and lower middle class. Building on and then going beyond Medicaid, it provided close to universal health care for U.S. children. It was also arguably the most bipartisan health move in recent decades, one reason it remains popular.

It seems hard to imagine anything similarly bipartisan in the near future, no matter how the 2020 elections turn out.

Not everyone has abandoned hope of progress — whether it’s called incremental or evolutionary.

“The American people are much more generous and much more united on the issue of insurance than are their elected officials,” said Blumenthal, the Commonwealth Fund head. “I think we believe that everyone should get the care they need when they need it. We disagree on how to accomplish it.”