The Pentagon's only maximum security prison, at the U.S. Army's Fort Leavenworth in Kansas, is one of the facilities being considered for placement of Guantanamo prisoners deemed too dangerous to release. Julie Denesha/Getty Images hide caption

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Captives separated by a fence conduct communal evening prayers at the Camp 6 prison building at the U.S. Naval Base at Guantanamo Bay, Cuba. Walter Michot/Miami Herald/TNS/Landov hide caption

itoggle caption Walter Michot/Miami Herald/TNS/Landov

Relatives of victims of the Sept. 11 attacks are periodically flown down to Guantanamo Bay, Cuba, to witness court proceedings against five men accused of plotting the attacks. For the witnesses of the most recent court session, the experience raised questions about justice, humanity and the ethics of the death penalty. Joe Raedle/Getty Images hide caption

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