Piercing the Fog - Air Force Historical Studies Office

Piercing the Fog
industrial condition, it was also influencing operational decisions on when to
bomb and toward what targets to shift bombing’s focus.
When .the Allied landing at Normandy compounded the pressures the
German military already faced on the eastern front, in Italy, and in the skies
over Germany, Enigma increasingly began to reveal shortages of supplies,
equipment, and personnel. This information influenced operational decisions in
the land war in western Europe. It also affected strategic air operations. Such
intelligence, particularly as it related to oil and fuel, confirmed the direction of
the strategic air campaign. By the fall of 1944, such insights had an even more
direct impact on that campaign. To a large extent, it was ULTRA that provided
the basis for several changes in target system priorities and the addition and
elimination of different target systems from strategic bombing priority lists.
ULTRA most fully encompassed the numerous aspects of the air war in
Europe through the insight it provided into the GAF. While stressing the
interrelated nature of air intelligence, the Eighth Air Force SSO added that the
reports ULTRA provided “of the strength, dispositions, composition, production,
wastage, reserves, and serviceability of the GAF . . . were the raw materials of
knowledge that produced most of our picture of the institution . . . [which] was
our major strategic target until April of 1944.”82 Through 1943, ULTRA
monitored the buildup of the German fighter defenses and the decision to
concentrate resources on the air defense of the Reich. While the aircrews who
engaged this expanding force could have offered some cogent observations
along these lines, ULTRA provided a more accurate monitoring of this buildup
as well as the command structure under which it was organized. It enabled the
Allies to trace at least some of the steps the enemy was prepared to take to
prevent Allied air attack, and it offered some insight into the enemy’s
perspective of the struggle for the skies over Germany.
It is not true that ULTRA enabled Allied intelligence to eavesdrop on every
decision of the German high command, for the Geheimschreiber remained a
difficult system to penetrate, and many reports and decisions went out in ways
other than radio messages. It must have been reassuring in the fall of 1943, as
the Eighth and Fifteenth Air Forces were suffering heavy casualties, to read the
following admission of the Air Officer for Fighters in Berlin: “The fighter and
heavy fighter formations have not been able to secure decisive success in our
defense against American four-engine formation^."^^ By the spring of 1944 it
was both ULTRA and photographic evidence that gave Spaatz an understanding
of the damage wrought by the AAF’s campaign against the German fighter
force. This Allied campaign, code named ARGUMENT, had been repeatedly
postponed since November 1943 because of poor weather. ARGUMENT’S
objective was a series of aerial assaults on German fighter production (from
ball-bearing manufacture to engine and airframe assembly) and on airfields and
aircraft storage areas. The Allied air commanders hoped to break German air
defenses to relieve pressure on the Combined Bomber Offensive (CBO) and to
76