U.S. Army Gen. Keith Alexander, commander of the U.S. Cyber Command, director of the National Security Agency (NSA), testifies during a Senate Appropriations Committee hearing on Capitol Hill, on Wednesday. Mark Wilson/Getty Images hide caption

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Sean Joyce, right, deputy director of the Federal Bureau of Investigation testifies before the House Select Intelligence Committee on Tuesday. Win McNamee/Getty Images hide caption

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U.S. Army Gen. Keith Alexander, commander of the U.S. Cyber Command, director of the National Security Agency (NSA), testifies during a Senate Appropriations Committee hearing on Capitol Hill, on Wednesday. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images