In his January 2015 State of the Union address, President Barack Obama pledged that the 13-year-old detention center at Guantánamo Bay Naval Station would finally be shuttered. “It’s time to finish the job,” he said. “I will not relent in my determination to shut it down. It’s not who we are.”

It was the clearest sign in years that Obama might fulfill his 2008 campaign promise to close the island prison where 114 men, most arrested in 2001-2002 on suspicion of being Taliban or al-Qaida fighters, continue to languish, the vast majority without charge. In July, his administration said it would soon submit a plan for closing the facility to Congress. Top military officials were dispatched to tour supermax prisons where detainees, including 70 from Yemen, eight from Afghanistan and the rest from 15 other countries, could be housed indefinitely.