More than half the detainees at the U.S. military prison in Guantanamo are on a hunger strike. Their lawyers as well as military officials say the protest reflects the level of despair felt by the prisoners there. Set up under President George W. Bush to hold terror suspects after 9/11, the prison today incarcerates 166 men. Most of them have never been charged with a crime. Detainee advocates want President Barack Obama to make good on his promise to close the Guantanamo facility. But others argue the detainees pose a national security threat -- even those who have been cleared for transfer to their home countries. A discussion of the future of Guantanamo's detainees.