Piercing the Fog - Air Force Historical Studies Office

Piercing the Fog
areas, the G-2 had good reason for refusing the A-2 freedom of action. The
G-2’s Military Intelligence Service never divulged to more than afew of A-2’s
most senior people (who were themselves prohibited from disclosing their
knowledge) the nature and extent of the ULTRA interception and decryption
system. That effort, pursued in conjunction with the British Government Code
and Cypher School, was too important to risk compromising. Unfortunately for
all concerned, the G-2’s refusal to be open about its activities left feelings of
uneasiness, deep frustration, and confusion among A-2 officers throughout the
war.”
Such conflicts were not limited to the Army; serious interservice difficulties
existed as well. For much of the war’s early years, the rival Navy and Army
cryptographers took potshots at one another. In March 1943, E. E. Stone of
Naval Intelligence (OP-20-G, the Navy decrypting agency) wrote to the
Director of Naval Communications, opposing the Army G-2’s suggestion to
merge Army and Navy radio intelligence. Stone remarked on the Army’s
frequent complaints that the Navy was not disclosing vital information by
pointing out that it was information from Navy decrypts of Japanese messages
that made possible the devastating success of General MacArthur’s Fifth Air
Force B-25s and Seventh Fleet PT boats at the battle of the Bismarck Sea.
Stone went on to state, “As for General Strong’s lMaj. Gen. George V. Strong,
G-21 remarks concerning the fact that allocation agreement prevents the Army
from working on material which is vital to it, the fact is the Army has
accomplished practically nothing whatsoever in obtaining operational radio
intelligence.” To support his case, Stone claimed that the Navy had just taken
over from the Army responsibility for a Japanese Army-Navy liaison
cryptographic system used in the Southwest Pacific that the Army had been
unable to solve in a year. Within a week, Stone said, “we made more advance
than the Army [had] in twelve months.””
Making matters the more sensitive, soon after Pearl Harbor and the Battle
of Midway, British officials had become uneasy; they did not believe Americans
could be trusted with full knowledge of the ULTRA effort and the
information it produced. The U.S. services were just too lax with security, the
British believed. British distress increased when the U.S. Navy staged the
“Yamamoto Mission” in April 1943; Great Britain temporarily broke off
negotiations with American officials for sharing ULTRA and MAGIC information.”
Not until the late spring of 1943 did a G-2 representative travel to
London to be initiated into the closed world of the operational use of ULTRA.
It was months later, perhaps not until early 1944, before General Arnold and his
A-2 gained access to British ULTRA information sent to the G-2 from England.
Arnold learned about the MAGIC Diplomatic Summaries shortly after the
attack on Pearl Harbor, but his formal knowledge of both the European and Far
East versions of ULTRA, the Allies’ most valuable World War I1 secret, came
much later. In England, the staff of the Eighth Air Force, which planned and
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