| Speer's hopes were not realized, largely because Ultra relayed to Allied air commanders the size and successes of German reconstruction efforts, as well as the enormous damage and dislocations to Germany's military forces that the bombing of the oil industry was causing. The intelligence officer who handled Ultra messages at the Eighth Air Force reported after the war that the intercepts indicated that shortages were general and not local. This fact, he testified, convinced "all concerned that the air offensive had uncovered a weak spot in the German economy and led to [the] exploitation of this weakness to the fullest extent." On the level of tactical intelligence, during the execution of Operation Overlord, Ultra also provided immensely useful information. Intercepts revealed a clear picture of German efforts and successes in attempting to repair damage that the Allied air campaign was causing to the railroad system of northern France. A mid-May staff appreciation signed by Field Marshal Gerd von Rundstedt, commander in chief West, warned that the Allies were aiming at the systematic destruction of the railway system and that the attacks had already hampered supply and troop movements. Ultra intelligence made clear to Allied tactical air commanders how effective the attacks on the bridge network throughout the invasion area were and the difficulties that German motorized and mechanized units were having in moving forward even at night.  Cryptanalysts at Bletchley Park Ultra also gave Western intelligence a glimpse of the location and strength of German fighter units, as well as the effectiveness of attacks carried out by Allied tactical aircraft on German air bases. Furthermore, these intercepts indicated when the Germans had completed repairs on damaged fields or whether they had decided to abandon operations permanently at particular locations. Armed with this information, the Allies pursued an intensive, well-orchestrated campaign that destroyed the Germans' base structure near the English Channel and invasion beaches. These attacks forced the Germans to abandon efforts to prepare bases close to the Channel and instead to select airfields far to the southeast, thereby disrupting German plans to reinforce Luftflotte 3 in response to the cross-Channel invasion. When the Germans did begin a postinvasion buildup of Luftflotte 3, the destruction of forward operating bases forced it to select new and inadequately prepared sites for reinforcements arriving from the Reich. Ultra intercepts proceeded to pick up information on much of the move, which indicated bases and arrival times for the reinforcing aircraft. Another substantial contribution of Ultra to Allied success was its use in conjunction with air-to-ground attacks. Ultra intercepts on June 9 and 10 revealed to Allied intelligence the exact location of General Leo Geyr von Schweppenburg's Panzer Group West headquarters. Obligingly, the Germans left their vehicles and radio equipment in the open. The subsequent air attack not only destroyed most of Panzer Group West's communications equipment but also killed seventeen officers, including the chief of staff. The strike effectively eliminated the headquarters and robbed the Germans of the only army organization they had in the West that was capable of handling large numbers of mobile divisions.  Why were the British able to break some of the most important German codes with such great regularity and thereby achieve such an impact on the course of the war? The Germans seem to have realized midway through the conflict that the Allies were receiving highly accurate intelligence about their intentions. Nevertheless, like postwar historians, they looked everywhere but at their own encrypted transmissions. Enthralled with the technological expertise that had gone into the construction of Enigma, the Germans excluded the possibility that the British could decrypt their signals. After the sinking of the great battleship Bismarck in May 1941 and the rapid clearance of the supply ships sent out ahead of her from the high seas, the Kriegsmarine did order an inquiry. Headed by a signals man (obviously with a vested interest in the results), the board of inquiry determined that the British could not possibly have compromised the Enigma system. Rather, the panel chose to blame the disaster on the machinations of the fiendishly clever British secret services. By 1943, the success of British anti-submarine measures in the Atlantic once again aroused German suspicions that their ciphers had been compromised. In fact, the commander of U-boats suggested to German naval intelligence that the British Admiralty had broken the codes: "B.D.U [the commander of U-boats] was invariably informed [in reply] that the ciphers were absolutely secure. Decrypting, if possible at all, could only be achieved with such an expenditure of effort and after so long a period of time that the results would be valueless." One British officer serving at Bletchley Park recalled that German "cryptographic experts were asked to take a fresh look at the impregnability of the Enigma. I heard that the result of this 'fresh look' appeared in our decodes, and that it was an emphatic reassertion of impregnability."  The Germans made a bad situation worse by failing to take even the most basic security measures to protect their ciphers. In fact, a significant portion of Bletchley Park's success was due to procedural mistakes that the Germans made in their message traffic. Among basic errors, the Germans started in midwar to reuse the discriminate and key sheets from previous months rather than generate new random selection tables. If that were not enough, they (particularly the Luftwaffe) provided a constant source of cribs, which were the presumed decrypted meanings of sections of intercepted text. They enabled the British to determine Enigma settings for codes already broken. The cribs turned up in the numerous, lengthy, and stereotyped official headings normally on routine reports and orders, all sent at regular times throughout the day. According to Gordon Welchman, who served at Bletchley Park for most of the war, "We developed a very friendly feeling for a German officer who sat in the Qattara Depression in North Africa for quite a long time reporting every day with the utmost regularity that he had nothing to report." The German navy proved no less susceptible to such mistakes. Dönitz's close control of the U-boat war in the Atlantic depended on an enormous volume of radio traffic. The volume itself was of inestimable help to the cryptanalysts at Bletchley Park. Although the Germans introduced a fourth rotor into the Enigma in March 1943, thereby threatening once again to impose a blackout on their North Atlantic operations, the new machines employed only a small fraction of their technical possibilities. Unfortunately for the U-boats, there was also considerable overlap between old and new Enigmas. As a result of these and other technical errors, the British were back into U-boat radio transmissions within ten days of the changeover. Furthermore, at about the same time, Bletchley Park decrypted a signal to U-boat headquarters indicating that the Germans were breaking the Allied merchant code.  One final incident should serve to underline the high price of German carelessness where security discipline was concerned. Bismarck had broken out into the central Atlantic in May 1941 on a raiding expedition. After sinking the battle cruiser HMS Hood, the battleship managed to slip away from shadowing British cruisers. The pursuing British admiral decided at 1800 hours on May 25 that the German battleship was making for Brest. Within an hour, the Admiralty had confirmation of that opinion through a Luftwaffe, not Kriegsmarine, intercept. Luftwaffe authorities had radioed their chief of staff, then visiting Athens during the German invasion of Crete, that Bismarck was heading for Brest. Obviously, there are important lessons that we can draw from these German errors. To begin with, as Patrick Beesly, who worked closely with the naval Ultra throughout the war, notes, "While each nation accepted the fact that its own cryptanalysts could read at least some of their enemy's ciphers, they were curiously blind to the fact that they themselves were being subjected to exactly the same form of eavesdropping." Above all, the Germans seem to have been overly impressed with their presumed superiority in technology. Thus, not only did they make elemental mistakes in their communications discipline, but they arrogantly refused to believe that their enemies might have technological and intelligence capabilities comparable to their own. In recent years, considerable interest has arisen regarding German operational and tactical competence on the field of battle. There is an important subheading to that competence. While historians and military analysts tell us that the Germans were extraordinarily proficient in the operational and tactical spheres, we should also recognize that the Germans were incredibly sloppy and careless in the fields of intelligence, communications, and logistics, and consistently (and ironically) held their opponents in contempt in those fields. We would be wise to examine the German example closely in all aspects of World War II. We can learn much from the Germans' high level of competence in the tactical and operational fields. Equally, we have much to learn from their failures in other areas. Above all, the German defeat in World War II suggests that to underestimate the capabilities and intelligence of one's enemies is to suffer dangerous and damaging consequences to one's own forces. |
