For decades, America led the world in humanitarian policies by creating a sanctuary for the oppressed, admitting more refugees annually than all other countries combined. That reputation eroded during Donald Trump’s presidency as he cut the number of refugees allowed in by more than 80%, and Canada replaced the U.S. as No. 1 for resettling people fleeing war and persecution. Trump has arguably changed the immigration system more than any U.S. president, thrilling supporters with an “America first” message and infuriating critics who call his signature domestic issue insular, xenophobic and even racist. The pain from a dismantling of the...