What is the National Security Agency?

Learn About the Intelligence Agency

Army Gen. Keith Alexander, commander of U.S. Cyber Command, director of the National Security Agency
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The National Security Agency is a highly specialized and vital unit of the American intelligence community that works to create and break secret codes, a science known as cryptology. The National Security Agency, or NSA, reports to the U.S. Department of Defense.

The work of the National Security Agency is done in secret and in the name of national security. The government did not even acknowledge the NSA existed for some time.

The National Security Agency's nickname is "No Such Agency."

What the NSA Does

The National Security Agency gathers intelligence by conducting surveillance on its adversaries through the collection of phone-call, email and Internet data.

The intelligence agency has two primary missions: preventing foreign adversaries from stealing sensitive or classified national security information from the United States, and collecting, processing and disseminating information from foreign signals for counterintelligence purposes.

History of the National Security Agency

The National Security Agency was created on Nov. 4, 1952, by President Harry S. Truman. The intelligence agency's foundation has its genesis in the work U.S. forces conducted during World War II in breaking German and Japanese codes, which it describes as a crucial factor in the Allied success against German U-Boats in the North Atlantic and victory at the Battle of Midway in the Pacific.

How the NSA is Difference From the FBI and CIA

The Central Intelligence Agency deals mostly with gathering intelligence on America's enemies and conducts covert operations overseas. The Federal Bureau of Investigation, on the other hand, operates within the U.S borders as a law-enforcement agency.

The NSA is primarily a foreign intelligence agency, meaning that it is authorized to collect data to prevent threats from foreign countries.

However, in 2013 it was revealed that the NSA and FBI had allegedly been collecting phone-call data from Verizon and other information from servers operated by none U.S. Internet companies including Microsoft, Yahoo, Google, Facebook, AOL, Skype, YouTube, and Apple.

Leadership of the NSA

The head of the National Security Agency/Central Security Service is appointed by the secretary of the Department of Defense and approved by the president. The NSA/CSS director must be a commissioned military officer who has earned at least three stars.

The current director of the intelligence agency is U.S. Army Gen. Keith B. Alexander.

The NSA and Civil Liberties

The surveillance activities of the NSA and every other intelligence agency often raise questions about civil liberties, and whether Americans are being subjected to unconstitutional invasions of privacy.

In a statement published on the NSA's website, agency deputy director John C. Inglis wrote:

"I'm often asked the question, 'What's more important – civil liberties or national security?' It's a false question; it's a false choice. At the end of the day, we must do both, and they are not irreconcilable. We have to find a way to ensure that we support the entirety of the Constitution – that was the intention of the framers of the Constitution, and that's what we do on a daily basis at the National Security Agency."

Still, the NSA has publicly acknowledged that it has inadvertently collected communications from some Americans without a warrant in the name of national security. It has not said how often that happens, though.

Who Oversees the NSA

The NSA's surveillance activities are governed by the U.S. Constitution and overseen by members of Congress, specifically members of the House Intelligence Subcommittee on Technical and Tactical Intelligence. It must also make requests through the Foreign Intelligence Surveillance Court.

Government surveillance agencies are also subject to review by the Privacy and Civil Liberties Oversight Board, which was created by Congress in 2004.