President Obama's executive order closing CIA "black sites" contains a little-noticed exception that allows the spy agency to continue to operate temporary detention facilities abroad. The provision illustrates that the president's order to shutter foreign-based prisons, known as black sites, is not airtight and that the Central Intelligence Agency still has options if it wants to hold terrorist suspects for several days at a time. Current and former U.S. officials, who spoke on the condition that they aren't identified because of the sensitivity of the subject, said such temporary facilities around the world will remain open, giving the administration the...