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

90 Pearl Harbor: The Seeds and Fruits of Infamy
cryptanalyzed by foreign powers.” And from Berlin to Tokyo on
May 3:
STAHMER called on me this day (evening?) and . . . said that
Germany maintains a fairly reliable intelligence organization
abroad (or—“in the U.S.”?), and according to information
obtained from the above mentioned organization it is quite
(or—”fairly”?) reliably established that the U.S. government is
reading Ambassador Nomura’s code messages. 27
As a result, the Japanese warned their embassies to exercise
extreme caution to protect the security of their messages. But,
fortunately for the United States, Japan did not heed, or did not
realize the full import of, the warnings sent her embassy in Berlin.
In any event, her diplomats continued to use their “Purple” diplomatic
code.
The American-Dutch-British (ADB)
Conversations, Singapore, April 1941
Toward the end of April the scene shifted to Singapore,
where a conference of American, Dutch, and British military
and naval offi cers, the so-called ADB Conversations, was held
in utmost secrecy. Th e principals dressed in mufti (civilian attire)
to conceal the nature of their visit. Th e agreement reached on
April 27 was subsequently signed by offi cials of the Associated
Powers—the United States, United Kingdom, Netherlands East
Indies, Australia, New Zealand, and India. 28 Th e United States
was the only signatory not then in the war.
27 Ibid., part 4, pp. 1860–61. Tokyo/Berlin cables; part 4, p. 1815, June 23, 1941
Tokyo to Mexico message cautioning vigilance: “Th ere are suspicions that they
[the Americans] read some of our [ Japan’s] codes.”
28 Ibid., part 15, pp. 1551–84 (Exhibit No. 50). American-Dutch-British
Conversations, Singapore, April, 1941 (Short Title, “A.D.B.”), Report.