Today in 1947: The National Security Act is Signed Into Law

President Truman Signing the National Security Act of 1947

Today marks the 66th anniversary of the signing of the National Security Act. The Act was signed into law on July 26, 1947 by President Harry Truman. At the time, the Act was hailed as a major accomplishment.

“This landmark legislation reorganized and modernized the US armed forces, foreign policy, and the Intelligence Community apparatus. It directed a major reorganization of the foreign policy and military establishments of the US government. And it created many of the institutions that US presidents would find useful when formulating and implementing foreign policy.”

The Act also established the Central Intelligence Agency (CIA) and made a distinction between foreign and domestic intelligence. Eventually, almost every word of the legislation’s intelligence section was debated. Some members of Congress “argued that the DCI [Director of Central Intelligence] and the new CIA could become a menace to civil liberties–an ‘American Gestapo.’ Administration witnesses alleviated this concern by reminding Congress that the Agency’s authorized mission would be foreign intelligence.”

Furthermore, the Act “consolidated the Department of War and the Department of the Navy into the National Military Establishment. The National Military Establishment, later renamed the ‘Department of Defense’ in 1949, was headed by the Secretary of Defense. The National Military Establishment began operations on September 18, 1947 – the day after the Senate confirmed James Forrestal as the first Secretary of Defense. The Act also created the Joint Chiefs of Staff and the National Security Council, both of which are a central part of national security operations today.”

Since 1947, the Act has been extensively amended. Revisions were made by “the USA PATRIOT Act, the Intelligence Reform and Terrorism Prevention Act of 2004 (IRTPA), and the National Security Intelligence Reform Act of 2004.”

For more resources from the HSDL on the National Security Act, the evolution of intelligence, and more, click here.

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