In a way, that’s how it’s supposed to work. Migrants are receiving the message that the right to seek asylum is open to them, because it is. The 1980 Refugee Act is unequivocal: People can cross into the country illegally and ask for asylum, and once they are here, the government is obligated to hear them out. That law codifies our commitment to the United Nations Refugee Convention, first drafted in the wake of the Holocaust to enshrine an ethical obligation known as “non-refoulement”: a government must not send people back to a country that will persecute them. The United...