In June 2012, when President Obama issued the executive order known as DACA—“deferred action on childhood arrivals”—he had a good moral case but a bad legal one. The order allowed illegal immigrants who had entered the country as minors—people who hadn’t come to America of their own will—to apply for a work permit and a renewable two-year exemption from deportation. Public opinion is broadly sympathetic to the plight of these youngsters, and rightly so: Many of them have little or no memory of their “home” countries. “Put yourself in their shoes,” the president said when he announced DACA. “Imagine you’ve done everything right your entire life—studied hard, worked hard, maybe even graduated at the top of your class—only to suddenly face the threat of deportation to a country that you know nothing about.”

The problem, as many Republicans pointed out then and since, is that Obama had no authority to write immigration law—as indeed he implicitly admitted by issuing the executive order only after he couldn’t get Congress to pass the DREAM Act. (The children of illegals, or “Dreamers,” get their sobriquet from the failed Development, Relief, and Education for Alien Minors Act.) President Trump has now ordered a six-month phase-out of DACA, and the 800,000 or so beneficiaries of the program—people who’ve volunteered their names and addresses to the federal government—are again in limbo.