Gregory Korte

USA TODAY

WASHINGTON — President Obama conceded defeat in his eight-year effort to close the U.S. military prison in Guantanamo Bay, Cuba, on Thursday, telling Congress that "history will cast a harsh judgment" on its decision to block the shutdown of the facility.

In a letter addressed to House Speaker Paul Ryan and Senate President Pro Tem Orrin Hatch, an exasperated Obama condemned members of Congress for "placing politics above the ongoing costs to taxpayers" and straining relationships with allies who have condemned what they see as human rights abuses at the prison.

Obama's letter to Congress, on his last full day as president, provided a symmetry to his tenure in office. On his second full day as president, Obama signed an executive order directing that the prison "shall be closed as soon as practicable, and no later than one year from the date of this order."

Eight years later, 41 detainees remain at the prison, considered too dangerous to transfer to another country, and without enough admissible evidence to bring them to trial. And under a law renewed by Congress every year, they cannot be transferred to prisons on U.S. soil.

Congressional restrictions on closing the facility "make no sense," Obama said. "No person has ever escaped one of our super-max or military prisons here, ever. There is simply no justification beyond politics for the Congress' insistence on keeping the facility open."

Obama called on Congress to close the prison after he leaves office, but President-elect Donald Trump and congressional leaders have pledged to keep it open. "There is bipartisan opposition, as expressed in multiple votes, to closing the secure facility in Guantanamo," said Don Stewart, a spokesman for Senate Majority Leader Mitch McConnell.

Also Thursday, the Pentagon announced the transfer of three detainees to the United Arab Emirates (Ravil Mingazov, Haji Wali Muhammed and Yassim Qasim Mohammed Ismail Qasim) and one to Saudi Arabia (Jabran al Qahtani). All were unanimously approved for transfer by the Periodic Review Board Obama established in his Jan. 22, 2009 executive order, a case-by-case process that looks at each detainee and the danger he poses.

"If this were easy, we would have closed Guantanamo years ago. But history will cast a harsh judgment on this aspect of our fight against terrorism and those of us who fail to bring it to a responsible end," Obama told Congress. "Guantanamo is contrary to our values and undermines our standing in the world, and it is long past time to end this chapter in our history."

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