Liberals and leftists have spent the last few months fighting a rearguard battle to protect the Obamacare status quo against attacks from the right. But after the death of Republican efforts to overhaul the health care system, opposition forces should shift their focus to what’s next. Preserving Obamacare is not enough. The time has come for universal health care through a single public health insurer that covers everyone in the country.

In the course of defending Obamacare, centrist pundits and institutions made a moral argument about the brutality of health uninsurance that also renders our current system totally indefensible. The Center for American Progress released a report showing that the Republican bill would cause around 200,000 more people to die over the next decade due to lack of health insurance, while Vox’s Ezra Klein described the CBO’s report detailing the collapse of health insurance coverage as “one of the most singularly devastating documents I’ve seen in American politics.”

If the 200,000 more deaths caused by switching from Obamacare to the defunct Republican plan is an unspeakable moral atrocity, then how do we justify sticking with Obamacare — which still leaves millions uninsured — rather than moving to a universal single-payer system? The math that produced CAP’s estimates, based on a study that concluded 1 person dies unnecessarily for every 830 people who lack health insurance, would imply that 300,000 additional deaths will be caused by Obamacare relative to a universal system where everyone is covered.

There is simply no longer a coherent centrist case for carrying on with Obamacare.

The Affordable Care Act did a lot of good, but the system it has left us with is still a disaster. According to Gallup, around 11.3% of adults currently lack health insurance. Despite the existence of Medicaid, uninsurance remains especially prevalent among those living in poverty. A Treasury study based on 2014 tax data concluded that the uninsurance rate for poor families was 10 times higher than it is for high-income families.

The problem is even worse than those numbers suggest. Tallies of people lacking health insurance are done at a particular point in time, meaning that they obscure just how often people move in and out of health insurance. Over half of the non-elderly population receive employer-sponsored insurance and, in a given year, over 40% of workers separate from their jobs. Not every separation results in an uninsurance spell, but many do.

Even if they manage to keep insurance when between jobs, workers and their families face the miserable hassle of draining their savings to preserve coverage through COBRA, signing up for health insurance on the Obamacare exchanges, or having to switch to an entirely different plan at their new job.

Even those who remain consistently insured face yet another coverage problem: high out-of-pocket expenses. According to the Federal Reserve’s most recent economic well-being report, 23% of Americans with health insurance forgo medical treatment every year because of an inability to pay.

A single-payer system is the most obvious way forward to finally achieve what all of our developed country peers did many decades ago: an easy-to-use, cost-effective health insurance system that covers everyone.

In many ways, the Obamacare experience provides the best argument for the universal alternative. Obamacare primarily increased health insurance coverage through two mechanisms: expanding Medicaid eligibility up the income ladder and creating an elaborate, subsidized individual marketplace. The Medicaid expansion, which closely approximates what a single-payer system would look like, was a smashing success. The individual marketplace, however, has been awful, with premiums increasing dramatically and insurance choices dwindling to two, one, or even zero options in some places.

Crucially, the superior performance of Medicaid was noted not just by wonks but also by ordinary people. Report after report after report has documented the existence of Medicaid envy: people bitter that they had been forced onto the individual marketplace because their income is too high for Medicaid. Contrary to the beliefs of Obamacare’s architects, it appears that people would much rather be on public health insurance, even on a stigmatized program for those on low incomes, than deal with private insurers.

The individual preference for public insurance is reflected in public polling as well. According to Gallup, 58% of Americans favor replacing the current system with a “federally funded healthcare program providing insurance for all Americans.” Among Democrats, support soars to 73%.

The Democratic party has generally ignored its voters on this issue, but that is starting to change. Around 60% of House Democrats are now cosponsors of John Conyers’ single-payer bill, the highest number recorded in the 12 years since it was first introduced. Democratic Sens. Elizabeth Warren and Kirsten Gillibrand, both of whom are rumored as likely 2020 presidential candidates, have recently announced their support for a single-payer system as well. The current frontrunner for the 2020 Democratic primary, Bernie Sanders, has long made single-payer one of his signature issues.

Now that the Republicans have failed, the time is ripe for a serious single-payer push. Policy institutions need to work hard to hammer out the details of a single-payer plan, and the Democratic party needs to stop fumbling around incompetently for a positive vision and instead unify behind the one already supported by the overwhelming majority of its voters.