Signals intelligence and codebreaking played a big part in the war with the US and UK solving important enemy cipher systems such as the German Enigma machine, the Italian Navy’s C-38m and the Japanese Navy’s JN-25 enciphered codebook. Similarly the Axis forces also had their successes, since the Germans codebreakers could eavesdrop on the radio-telephone conversations of Franklin Roosevelt and Winston Churchill, they could decode the messages of the British and US Navies during their convoy operations in the Atlantic and together with the Japanese and Finns they could solve State Department messages (both low and high level) from embassies around the world.Obviously the only way to identify the full extent of the Axis successes was to capture their archives and interrogate the most important people in their signal intelligence agencies. Several TICOM teams took part in these operations and they were able to capture material of great value. This material was then examined by the US and UK signal intelligence agencies, with a US report from 1952 saying:
‘TICOM documents have since 1945 proved to be of invaluable help to a number of cryptanalytic sections working on countries in the Western Area and a resurvey of the documents available is currently bringing to light additional material which will considerably expand its usefulness’Unfortunately the TICOM material was kept classified till the 2000’s with the result that WWII histories do not have accurate information on Axis codebreaking successes.
Why did the NSA and GCHQ keep this material classified for so long? The NSA’s classification guide for SIGINT Material Dating from 16 August 1945 – 31 December 1967 mentions the TICOM material:
The guide says that the TICOM documents should be kept classified for 75 years and both the US and UK followed this rule almost to the end. Thankfully most of the reports have been released in the last five years (by the NSA) and since the mid 2000’s (by GCHQ). Still couldn’t they have released it sooner? Information on their own successes was released much earlier, either at the end of the war (US Navy successes) or in the 1970’s (Enigma story).The guide says: ‘Various levels of harm to national security can be expected if this material were to be declassified, depending on the particular information being revealed’
Come on! These reports deal with ‘ancient’ cipher systems. There is no way that they could damage US national security in any way. Both the NSA and GCHQ need to be reasonable and release the rest of the TICOM reports. Then historians will finally have the information they need to write a balanced account of Axis and Allied signals intelligence operations in WWII.