National Security Agency ( NSA) is a part of the United States government. It was started in 1952, and the main office is in Maryland, USA.
goal is to protect the US people. They do this by
NSA also protects the U.S. from evesdropping and SIGINT spying by foreign governments and agencies. This is protection against "penetration and network warfare".
 The agency does this by  clandestine means, among which are  bugging electronic systems, and  sabotaging their computer networks with viral software.  
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↑ "About NSA: Mission". National Security Agency . http://www.nsa.gov/about/mission/index.shtml . Retrieved September 14, 2014.
↑ Nakashima, Ellen. January 26, 2008. Bush order expands network monitoring. The . Retrieved February 9, 2008. Washington Post 
↑ Executive Order 13470 — , July 30, 2008 (PDF)  2008 Amendments to Executive Order 12333], United States Intelligence Activities
↑ Malkin, Bonnie. NSA surveillance: US bugged EU offices. The Daily Telegraph, June 30, 2013
↑ Ngak, Chenda. , NSA leaker Snowden claimed U.S. and Israel co-wrote Stuxnet virus CBS, July 9, 2013
↑ Bamford, James. , Wired Magazine, June 12, 2013. The Secret War