NSAM 347: Release of Public Information on Nuclear Tests (1966)


The Johnson Administration’s National Security Memorandum (NSAM) 347: “Release of Public Information Concerning Soviet, French, and Communist Chinese Nuclear Tests,” dated May 26, 1966, and signed by LBJ National Security Advisor  Walt W. Rostow, follows in line with previous presidential administrations in restricting public knowledge regarding foreign nuclear tests.***

In part, NSAM 347 states:

The President has directed that all recipients of classified intelligence information regarding Soviet, French and Communist Chinese nuclear tests take all feasible steps to prevent unauthorized disclosure of the information. Such action is essential to safeguard intelligence sources and methods in obtaining this information and to minimize speculation concerning the significance of data obtained from such tests. [emphasis added]

I include NSAM 347 hereas it represents the notoriously secret side of atomic history, which rests uneasily with public education initiatives such as the Smyth Report, the plethora of civil defense documents that openly report health risks of (global) radiation and fallout, and debates in the media on atomic weapons, led by among other media giants of the period, Life magazine (volume 28, 1950: p. 91+).

As an aside, the National Security Archive’s briefing book  U.S. Intelligence and the Detection of the First Soviet Nuclear Test, September 1949, edited by William Burr, examines declassified documents relating to how the “U.S. Air Force, the Atomic Energy Commission, and U.S. scientific intelligence worked together to detect a nuclear test that intelligence analysts, still unaware of the extent to which the Soviets had penetrated the Manhattan Project, did not expect so soon.” The first Soviet nuclear weapons test (termed “Joe-1” by U.S. intelligence) was conducted in Semipalatinsk on August 20, 1949.

*** Kennedy NSAM 176 (August 01, 1962), limited public knowledge of only Soviet nuclear tests and was used as a basis for NSAM 347.

“National Security Action Memoranda were formal presidential directives dealing with national security affairs during the Kennedy and Johnson administrations; in addition, they were used as directives that studies be undertaken involving national security policy and objectives. They were numbered consecutively as they were produced. ” (See Paul Kesaris, ed. A Guide to the Microfilm Edition of Documents of the National Security Council, Seventh Supplement, compiled by Blair D. Hydrick, UMI, 1996.