Pearl Harbor: The Seeds and Fruits of Infamy - Ludwig von Mises ...

Army Pearl Harbor Board 471
Saturday, September 30, the board sent Marshall still more questions.
114 In the meantime, two important witnesses testifi ed—
Army courier Colonel Rufus Bratton and Navy Captain L.F.
Saff ord.
Colonel Bratton Testifies About
Japanese Intercepts
At the time of the attack, Colonel Rufus S. Bratton had been
Chief, Far Eastern Section G-2 and Army Courier. When testifying
before the APHB, 115 he referred to a memorandum written
December 10 detailing the events of December 7, 116 and to
a “Summary of Far Eastern Documents,” based on documents
from 1937–1941 and compiled August 1943 by the Far Eastern
section, intelligence group, and by War Department’s G-2. It had
been compiled for submission to the Army chief of staff and the
president. Bratton was “conversant with the Japanese language.” 117
Although he had not been involved with the actual interception
and decoding of the Japanese messages on which that Summary
had been based—that had been the responsibility of the Army’s
Signal Intelligence Service (S.I.S.) and the Navy’s Offi ce of Naval
Intelligence (O.N.I.)—he had seen “all secret messages relating
to the Japanese situation received by the War Department.” 118 In
August 1940, U.S, cryptographers had succeeded in deciphering
the Japanese diplomatic code, which became known as “purple,”
and ever since then we had been reading many, if not most, of
the Japanese intercepts transmitted in this code. Th e intelligence
derived from this source was considered so valuable that it had
been code-named MAGIC. Much of the information Kimmel
114Ibid., pp. 2413–15.
115Ibid., pp. 2335–55.
116Ibid., pp. 2346–47.
117Ibid., p. 2338.
118Ibid., p. 2335.