“Even if people would say these things behind closed doors, it was never articulated in public fashion the way that Trump did,” says Ruth Wasem, a professor of public policy practice at the University of Texas who specializes in asylum. “Now, that vitriol towards refugees — once that taboo is crossed, it’s hard to put the genie back in the bottle.”

Since World War II, presidents of both parties have accepted millions of asylum seekers, honoring the treaties and statutes that the U.S. agreed to over the decades after the Holocaust affirming a right to refuge for people fleeing persecution. Taking in refugees has never been particularly popular in American public opinion, leaving the system vulnerable to a populist political attack, but governmental leaders had been able to invoke notions of America’s standing in the world to depoliticize asylum policy and keep commitments relatively steady. No longer.

Since Trump mainly used executive action — circumventing Congress — to change policy, it may not be hard for Biden to reopen the U.S. to refugees and asylum seekers over the next four years. But in the longer term, closing the political divide that Trump widened on asylum will prove much more challenging. Thanks to the last administration, asylum in the U.S., once globally reliable, has become like the carpeting in the Oval Office: something that can be torn up and remade from president to president.