Andrzej Dabrowa, Ph.D.
15. Enigma security
All Bletchley Park recruits were required to sign the Official Secrets Act and keep mum about their activities. The need to know was initially enforced but was later dropped for those who required constant interactions between various sections. As far as outsiders were concerned, only selected high rank commanding officers would get both the information and the source. Lower rank officers would get the information suitably formatted to conceal any Enigma connection.
There were very few security lapses and two of them occurred when the Bletchley Park members mentioned their work to relatives. A third occurred during a security sweep when security officers managed to "acquire" badges and were able to wander unchallenged through the compound. However, the most important security leak occurred when General Rommel got sick and requested to be relived from his command. This information was decrypted and passed to Whitehall ministries. Soon after that, rumours about Rommel's illness began to appear in the British press and Churchill ordered a formal inquiry which established new security procedure. This now required Enigma intelligence reports to be sent first to the Chief of British Intelligence, General S. Menzies, who in turn distributed them to the ministries with proper warning.
Since the Germans had no knowledge of Bletchley Park operation there were no German spies involved but it was infiltrated by Soviet spies. One of them was John Cairncross who worked in Hut 3 for about a year. He maintained his apartment in London and travelled there for weekends. In London, he passed a selection of decrypts about the Russian front to his Soviet handler. Though the British supplied that information to the Soviets, John Cairncross compromised the Enigma secret. The second Soviet spy is only known by the code name of "Baron". His presence at Bletchley Park was known before 1942 from decrypts of Soviet messages from London to Moscow. The third spy was W. Weisband who worked as a Russian language specialist at Arlington Hall.
No members of the Bletchley Park organisation were ever in danger of being arrested by the Germans. However, both the Polish and the French members of the "Cadix" team were exposed to the German occupying forces and a number of them were arrested and tortured. G. Langer and M. Ciezki were arrested and sent to concentration camp. They were interrogated by the Gestapo and admitted breaking the Enigma cipher before the war. However, they convinced the Germans that they were unable to break the cipher once the war started. Both survived the ordeal and went to England to join their intelligence colleagues. There they were ostracized for their inability to evacuate the Franco-Polish team safely to England.
M. Rejewski and H. Zygalsld were arrested by a Spanish border patrol while crossing the border from France to Spain. They were put in a Spanish prison camp where they were interrogated. After their release to civilian control they managed to escape through Portugal and Gibraltar to safety in Britain. There they worked on German cipher but were not allowed to join Bletchley Park. A. Pallufe and E. Fokczynski were sent to a concentration camp where they both perished. G. Bertrand was arrested by the Germans and agreed to cooperate. However, he gave only the names of French agents who were safely out of the country. Since this occurred near the invasion of France and to be on the save side General Menzies, Chief of British Intelligence, decided to bring him to Britain. R. Lemoine was arrested and refused to be a double agent but betrayed Hans Thilo-Smith. None of the above mentioned betrayed the secret that the Enigma cipher had been broken.
The major security lapses occurred outside the Bletchley Park and happened when end users of the Enigma intelligence information failed to properly structure the military responses in order to protect the source of the information. This would include a "post factum" organisation of airborne or seaborne area sweeps that would be recognised by the Germans as "routine" activities. Also, any boarding of a German naval vessel to gain material relating to Enigma required that it be very swift and the vessel sunk as soon as possible. All the crew had to be taken prisoner and kept in total isolation until the end of the war.
In late 1941, one example of poor planning was two closely spaced attacks on German U-boats and supply ships. Although the attacks were a complete surprise and both vessels were sunk, many survivors made it to France to give eye witness accounts of the encounter. Luckily for the Allies the German inquiry into this event did not find any evidence that the Enigma cipher was compromised. The second example occurred when US command pursued an aggressive policy of actions against the enemy based on Enigma decrypt intelligence. This was strongly opposed by the British. In mid-1944, a US Naval Task Force off the coast of West Africa detected and attacked a German U-boat. After the surrender of U-505 it was boarded and all the documents removed to the attacking vessel, USS Guadalcanal. Captain Gallery then made a serious error of judgment and decided to tow the U-boat to the neutral port of Dakar which would have jeopardised the Enigma secret. Consequently, orders went out for the U-boat and the prisoners to be taken by another ship and transported to the USA where the German prisoners were kept in complete isolation until 1947.
There were a number of similar actions where poor Allied planning caused the German military to question Enigma security but the German scientists always maintained that the Enigma cipher could not be broken, even with large resources. They were wrong - three Polish cryptologists, working on a small budget, were able to break the Enigma cipher and showed the Allies how to read German orders.
The final act of security enforcement begun when the Allies invaded the continent of Europe. As the troops moved in and German military equipment was captured, all Enigma, machines and documentation were seized and put under very strict security. Out of the 30,000 to 60,000 Enigmas manufactured, only a few escaped that fate. We can only guess what happened to them. Some of them were later used in Burma and some were probably sold to unsuspecting newly emerging nations.
(c) 2003 A R Dabrowa