Former Army intelligence analyst Bradley Manning, found guilty of espionage and theft Tuesday, could face a lengthy prison sentence. A penalty hearing for Manning begins today. Saul Loeb/AFP/Getty Images hide caption

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An activist wears pictures of leakers Edward Snowden and Bradley Manning during a demonstration against the electonic surveillance tactics of the NSA, in Berlin on Saturday. Sean Gallup/Getty Images hide caption

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Hackers attend the 2011 Def Con conference in Las Vegas. The 2013 conference as well as the Black Hat hacker conference kicks off this week. Isaac Brekken/AP hide caption

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Supporters of U.S. Army Pfc. Bradley Manning protest his detention by marching around the perimeter and blocking the gates of Fort McNair in Washington, D.C., on the final day of closing arguments in his military trial Friday. Chip Somodevilla/Getty Images hide caption

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Protesters demonstrate against alleged NSA surveillance in Germany during a rally in Hannover, Germany, on Saturday. Peter Steffen/AP hide caption

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Edward Snowden, seen during a video interview with The Guardian. Glenn Greenwald/Laura Poitras/EPA/Landov hide caption

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Lee Harvey Oswald, the assassin of President Kennedy in 1963, had defected to the Soviet Union several years earlier, but returned to the U.S. after becoming disillusioned with that country. He is shown here in a Dallas police station after his arrest for Kennedy's shooting. AP hide caption

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