National Security officials head to Capitol Hill Tuesday to defend data surveillance programs that they say have prevented more than 50 attacks in the United States.<br/> <br />General Keith Alexander, is the director of the U.S. National Security Agency.<br/> <br />(SOUNDBITE) (English) GENERAL KEITH ALEXANDER, THE DIRECTOR OF THE U.S. NATIONAL SECURITY AGENCY, SAYING:<br/> <br />"In recent years these programs, together with other intelligence, have protected the U.S. and our allies from terrorist threats across the globe to include helping prevent the terrorist--, the potential terrorist events over 50 times since 9/11."<br/> <br />Sean Joyce the Deputy Director of the FBI offered details.<br/> <br />(SOUNDBITE) (English) SEAN JOYCE, THE DEPUTY DIRECTOR OF THE FEDERAL BUREAU OF INVESTIGATION, SAYING:<br/> <br />"In the fall of 2009, NSA using 702 authority intercepted an e-mail from a terrorist located in Pakistan. That individual was talking with an individual located inside the United States, talking about pe
