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

Army Pearl Harbor Board 475
APHB members Russell and Grunert then asked Bratton
how it would aff ect the Japanese if they learned then—1944—
that we had intercepted a “Winds Execute” message in 1941. He
did not believe those code words were being used by the Japanese
today. He was then asked if the Japanese knew we had intercepted
these messages and had broken that code before the war,
would it give them any information as to whether or not we had
broken the code they are using today.
Bratton: Oh, yes, sir, it would, because these code phrases are a
code within a cipher. . . . Th e whole message about this “Winds”
signal was in a very secret cipher. . . .
Grunert: And they are continung to use that cipher? . . .
Th erefore, the danger that any leak of this thing might aff ect
the war eff ort exists now as it has in the past?
Bratton: Yes, sir. 130
On this point, Navy Captain Saff ord fl atly disagreed, as the
APHB soon learned.
Captain L.F. Safford Describes the
Japanese “Winds Code” Intercepts
As head of the communications security division, naval
operations, in 1941, Saff ord had been much involved with naval
intelligence information. 131 He remembered many details from
1941. However, when testifying before the APHB on October
2, he consulted a record of the intercepts prepared more recently
(November–December 1943 and January–March 1944) from
original sources borrowed from OP20G, i.e., “the communication
intelligence section, or communication division, of Naval
130 Ibid., pp. 2340–41.
131 Ibid., pp. 2361–400.