Part 2 – Feedback phase
The phase of misinformation of the ‘closed loop’ deception was followed by a feedback phase, enabling the XX Committee to ascertain the extent of the German credulity.
The role of Ultra
British were able to read encrypted German message traffic, often as fast as the intended recipients. Government Code and Cypher School (GC&CS) had a good command of codebreaking computers, allowing the deciphering of German signals including the Enigma machine, considered as unbreakable by Germany but broken by Polish experts who transmitted their methods to Britain. The Fortitude deception plan has been used in parallel with the use of Ultra, the codename given to the ability to intercept and decipher German signals encrypted with the Enigma machine. Those communications mainly involved the German Navy, Army and Air Forces, but also the Abwehr, supplying the British intelligence services with both information concerning the troops movements and the management of intelligence. As a consequence, Ultra provided the Allies with valuable information concerning the enemy’s moves and the degree of credence he was according to the false information provided by the XX Committee agents and by physical deception. Indeed General Omar Bradley, who was in command of all U.S. ground forces invading Germany from the West, says in its autobiography “Ultra was central to Fortitude’s conception and execution and provided a continuous monitor on German reactions to it”. Thanks to Ultra, Britain was in a position to monitor the Germans’ reaction to the misinformation reported by double agents. The feedback was crucial for achieving deception objectives, allowing the XX Committee to emphasize points the Germans missed and to modify the points they distrusted, making the deception more effective. For instance, the Ultra interception of a signal from the German Navy planning a military exercise in the area of Calais between 21 and 27 May confirmed that Germany granted a high degree of confidence to the deception plan. An even more valuable feedback was provided on June 1st, five days before D-Day, when a German message referred to ‘an unquestionable’ centre of gravity of Allied forces in south-east England.
This message revealed the confidence the Germans had in fictitious Allied positions, preparing a landing in Pas-de-Calais. Moreover, the Committee was able to match the controlled linkage to what the Abwehr expected to hear, to play on Germans’ existing fear. Indeed, some German communications mentioned the Führer Directive n°51 of November 1943, raising the issue of probable “diversionary attacks” forerunning a major invasion. The feedback was also essential to the deception plans in the extent that it allowed to keep the XX Committee double agents believable. If the Abwehr was showing any sign of mistrust in the agents’ reports, these latters were then able to disavow it or to provide more evidences. A striking example is the one of the notional First United States Army Group (FUSAG), supposedly stationed near Dover. In April and May 1944, two intercepted signals emitted doubts concerning the identification of the army. In response, the XX Committee fictitiously posted the agent Brutus to the FUSAG staff with the order to provide totally made up information about it, giving more credibility to the imaginary army and to the threat it represented.
The role of the German Intelligence Services
Nevertheless, the German use of radio was limited and generally restricted to emergency transmissions. Indeed, large land-line communications existed in France and Germany. The pieces of information the British intelligence services were likely to exploit in deception plans were thus restrained. Ultra reveal itself to be invaluable particularly after Operation Neptune, the amphibious landing on Normandy coast, was triggered, because of the increase of emergency communications. Before the D-Day, Ultra used to intercept six or seven signals a day. After the invasion of Normandy, the number of signal dramatically increased until twenty or thirty per day, and sometimes more. This important rise allowed the British intelligence services to know if Germany definitely trusted the story they had been implemented for months, and to what extend the deception plan was influencing its appreciation of the situation. One can say that the success of Operation Fortitude was partly due to the mastery of the feedback loop, but also largely to the poor quality of German intelligence. Indeed, the XX Committee did not obtained day-to-day information about the Germans credulity, and was not necessarily able to definitely ascertain the extent of it. Yet, for the reason that the Abwehr was incapable and that the German command system was biased, this credulity was tremendous. Moreover, the Abwehr itself directly supplied elements of feedback intelligence to the double agents. The agents’ controllers provided them with questionnaires, in order to make them focus on their main points of interest. By the way, they revealed valuable information about the preparation of future German operations, as well as what the Abwehr knew and didn’t knew. The poor quality of the
German intelligence can be explained by several factors. The conjunction of early military successes and assumed racial superiority led the German high command to over-confidence and loss of touch with reality. As a result they were overconfident concerning the infallibility of the Enigma machine, believing the codes were unbreakable. Yet, Polish mathematicians had broken the coding scheme as soon as 1932, and then passed their knowledge to the British in 1939, after the outbreak of war. The confidence in the unbreakability of Enigma codes and in the security of their communication made the Germans using it throughout the whole war, putting themselves in a hazardous position by risking to be spied. Furthermore, the authoritarian structure of the Nazi state and the cult of personality contributed to the blindness and credulity of German intelligence services. Indeed, by making Hitler’s judgment infallible, it encouraged the pursuit of inaccurate visions of the strategic situation, intensifying the potential of being deceived.
As a conclusion, Operation Fortitude was interpreted as a ‘closed loop’ deception operation for straightforward factors. Indeed, it aimed at mislead Germany concerning the time and place of the amphibious landing in France in order to maximize its potential for success. This essay examined that the British intelligence services did not only disposed of the means to misinform German forces, but also to ensure the extent of the German credulity in the deception plan. Notwithstanding the poor quality of German intelligence services, together with its lack of precaution and its overconfidence, conducted it to act as to facilitate both the disinformation and the feedback phases.
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