Donald Trump says he will use a detention center at Guantánamo Bay to hold tens of thousands of criminal immigrants in the U.S. illegally.

Human rights groups have accused U.S. authorities of using Guantánamo Bay for decades to detain migrants fleeing Haiti, Cuba and other Caribbean nations.

The president has instructed officials to “begin preparing” a 30,000-person “migrant facility” at Guantánamo Bay. The list of concerns is not short.