The National Security Agency (NSA) is an intelligence agency of the United States Department of Defense, under the authority of the Director of National Intelligence (DNI). The NSA is responsible for global monitoring, collection, and processing of information and data for foreign and domestic intelligence and counterintelligence purposes, specializing in a discipline known as signals intelligence (SIGINT). The NSA is also tasked with the protection of U.S. communications networks and information systems. The NSA relies on a variety of measures to accomplish its mission, the majority of which are clandestine. The NSA has roughly 32,000 employees.
NSA headquarters in Fort Meade, Maryland, c. 1986
Black Chamber cryptanalytic work sheet for solving Japanese diplomatic cipher, 1919
Protesters against NSA data mining in Berlin wearing Chelsea Manning and Edward Snowden masks
Intercepted packages are opened carefully by NSA employees
United States Department of Defense
The United States Department of Defense is an executive branch department of the federal government of the United States charged with coordinating and supervising all agencies and functions of the U.S. government directly related to national security and the United States Armed Forces. As of June 2022, the U.S. Department of Defense is the largest employer in the world, with over 1.34 million active-duty service members, including soldiers, marines, sailors, airmen, and guardians. The Department of Defense also maintains over 778,000 National Guard and reservists, and over 747,000 civilians bringing the total to over 2.87 million employees. Headquartered at the Pentagon in Arlington County, Virginia, just outside Washington, D.C., the Department of Defense's stated mission is to provide "the military forces needed to deter war and ensure our nation's security".
President Truman signs the National Security Act Amendment of 1949
A December 2013 Department of Defense organizational chart
Joint Chiefs of Staff and Joint Staff organizational chart