Communications Intelligence

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MAGIC was the "compartmentation code assigned to Japanese diplomatic traffic that was intercepted by American intelligence as a result of the breaking of Purple, the Japanese diplomatic code, in 1940." O'Toole, Encyclopedia, p. 285.

Beginning in 1940, the British designated as "Ultra" the material being recovered from the German Enigma machine. Winterbotham, The Ultra Spy, p. 202. Later, the term was applied to "all intelligence recovered from cryptanalysis, regardless of its national origin.... Thus ULTRA came to include the American MAGIC, the U.S. designation for intercepts of Japanese diplomatic communications." Sexton, Signals Intelligence in World War II, p. xxiii.

See Gilman McDonald [CDR/USNR (Ret.)], "About ULTRA: Fact and Fiction," Intelligencer 14, no. 2 (Winter-Spring 2005): 113-117 (with editorial additions, 117-120), for the argument that the term ULTRA was simply a security classification or label applied to the U.S. Top Secret or above the British Most Secret.

Ralph Erskine contributes the following: "A signal of 20 August 1944 (cited in full in G. E. Colpoys, 'Admiralty Use of Special Intelligence in Naval Operations' (TNA PRO ADM 223/88), 43, and replacing signals of 28 January 1943 and 1 November 1943), makes it clear that for all three British services Ultra was 'a short title' for 'special intelligence', with both terms meaning "intelligence resulting from the solution of high grade codes and ciphers."

Reference Materials

U.S.-U.K. Cooperation:

A - B

C - O

P - Z

Materials on MAGIC:

William F. Friedman

A - B

C - J

K - R

S - Z

The Chicago Tribune, Midway, and MAGIC

Materials on ULTRA

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