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The National Security Agency

The National Security Agency (NSA) is the lineal successor to a number of U.S. code‐breaking organizations and projects before and during World War II— Herbert Yardley's “Black Chamber,” MAGIC, and ULTRA.

Created by President Harry S. Truman in a secret directive in 1952, NSA is responsible for the protection of U.S. coded communications and for intercepting and breaking foreign communications—customarily referred to as signals intelligence (SIGINT). SIGINT is one of four major intelligence collection branches; it is highly prized by intelligence analysts and policy customers as SIGINT often reveals plans and intentions.

A three‐star flag officer heads NSA, rotating among the services. Budget and personnel figures are classified, although NSA is widely acknowledged to be the largest of the intelligence agencies. James Bamford in 1982 estimated a budget of over $1 billion and 80,000–120,000 employees. NSA's major components are regional operational groups: the former Soviet Union and allies; communist Asian nations; Third World and others.

Like all other intelligence agencies, NSA came under post–Cold War pressure to reduce size and costs while maintaining production and modernizing its workforce skills. A longtime leader in computer technology, NSA in the 1990s has been involved in a debate over a data encryption standard, which would allow enciphering nongovernmental data and which NSA opposed. It is assumed that NSA will play a role in “information warfare” (computer attacks on communications, financial, and other nodes) as this becomes both a new capability and a growing defensive concern.
[See also Intelligence, Military and Political.]


George A. Brownell , The Origin and Development of the National Security Agency, 1981.
James Bamford , The Puzzle Palace: A Report on America's Most Secret Agency, 1982.

Mark M. Lowenthal

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