I’m not sure anybody is ready to put into words what transpired Tuesday night. Donald Trump, a know-nothing demagogue who rallied working-class white voters to his campaign by scapegoating Hispanics and Muslims, who winked to white nationalists, who promised to shred America’s traditional foreign policy alliances, who shattered basic norms like releasing his tax returns, who spent several days of his candidacy insulting the parents of a fallen U.S. soldier, has won the presidency of the United States. He is a political figure unlike any in our history, and it is hard to fathom what his victory will mean for the future of our country and national character.

But speaking purely from a policy perspective, I do think it is clear what we are about to lose. It starts with the erasure of the Obama era, which gave America its first true steps toward a more progressive, compassionate government after some three decades of conservative policy dominance—all while helping the country gradually recover from the worst economic catastrophe since the Great Depression. Trump will happily undo every piece of the president’s legacy that he can, if only to satisfy his personal vendetta against the man. And he will have the aid of Republicans in the House and Senate, who have been biding their time since 2010 for the opportunity roll back Obama’s key achievements. Trump and House Speaker Paul Ryan may not see eye to eye on everything. But they do share a desire to blot out the past eight years.

Obamacare is, of course, in deep danger. For all its faults, the law has helped extend health insurance to some 20 million Americans who previously lacked coverage. It now stands to be repealed—and possibly replaced with some insubstantial, faux version of reform. It will only take 51 votes in the Senate to do it thanks to the chamber’s budget reconciliation rules. Furthermore, Trump has said he would turn Medicaid into a block grant program, which would likely leave millions more uninsured.

For technical reasons, some of Obama’s other achievements may be trickier to dismantle wholesale, but at the very least Trump will be able to erode them badly. (And if Republicans eliminate the filibuster, it won’t be tricky at all.) Trump has promised to junk the Environmental Protection Agency’s Clean Power Plan, the president’s legacy of fighting climate change, and Dodd-Frank’s Wall Street reforms. The planet will continue to heat. The markets will be free to run wild. We may very likely collapse into another recession.

In many ways, it will almost be as if the past eight years never happened. And what then? It’s possible the Trump era might become a truly radical experiment in conservative government: He has promised enormous corporate and personal income tax cuts that would favor the rich. Presumably, something will be cut to pay for it—and I think it’s safe to assume that something will be programs for aiding the poor. If so, America would be a hungrier, sicker, more unequal place in the future.

You can speculate more—about trade wars, about what on earth his immigration policy will actually be. None of this touches his terrifying authoritarian instincts, his frighteningly incoherent foreign policy pronouncements, or that he will be able to pick at least one Supreme Court justice. But in the shock of this moment, what I personally keep coming back to is the future America has chosen to turn its back on. The past eight years made halting progress toward a more fair government and economy. Right now, we can only mourn that progress’s imminent loss.

See more Slate coverage of the election.