Sunday, June 21, 2015

TICOM reports and the NSA’s classification policy

At the end of WWII the Anglo-American Allies initiated a program called TICOM - Target Intelligence Committee, whose goal was to capture the files and personnel of the Axis signal intelligence agencies.

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.

Friday, June 12, 2015


1). In State Department’s strip cipher – reuse of alphabet strips and key lists i added the following US report of November 1943:

(15). Dr Wolfgang Franz, who has in charge of OKW/Chi’s strip cipher program said in TICOM DF-176, p9 ‘All told, some 28 circuits were solved at the Bureau under my guidance, likewise six numerical keys-some of them only in part

Monday, June 1, 2015

The compromise of the State Department’s strip cipher – Things that don’t add up..

During WWII the US State Department used several cryptosystems in order to protect its radio communications from the Axis powers. The main systems used were the unenciphered Gray and Brown codebooks along with the enciphered codes A1, B1, C1, D1 and the new M-138 strip cipher. 

In the period 1940-1944 German, Japanese and Finnish codebreakers could solve State Department messages (both low and high level) from embassies around the world. The M-138-A strip cipher was the State Department’s high level system and it was used extensively during that period. Although we still don’t know the full story the information available points to a serious compromise both of the circular traffic (Washington to all embassies) and special traffic (Washington to specific embassy). In this area there was cooperation between Germany, Japan and Finland. The German success was made possible thanks to alphabet strips and key lists they received from the Japanese in 1941 and these were passed on by the Germans to their Finnish allies in 1942. The Finnish codebreakers solved several diplomatic links in that year and in 1943 started sharing their findings with the Japanese. German and Finnish codebreakers cooperated in the solution of the strips during the war, with visits of personnel to each country. The Axis codebreakers took advantage of mistakes in the use of the strip cipher by the State Department’s cipher unit.
Apart from purely diplomatic traffic the Axis powers were also able to read some of the messages of other organizations that were occasionally enciphered with State Department systems, such as the Office of Strategic Services, the Office of War Information and the Military Intelligence Service.