Soviet SIGINT I.

This is coolbert:

Soviet SIGINT [signals intelligence].

From a Military Thoughts blog entry from way back when now:

 "Ciphering machines started to be used about this time: 'Enigma' (Germany) . . . 'Purple Code' (Japan) . . . now is a well-known fact: 'Enigma' had been broken by American and British specialists, the 'Purple Code'; – by American and Russian code-breakers in 1939 – 1940."

"That the Russian was able to “read” the Japanese Purple crypto machine was news to me. I have not seen this referenced anywhere else. My understanding was that the Americans and the British each independently arrived at a cryptanalytic solution to Purple, but NOT the Russian."

NOW thanks to Google books and: "The sword and the shield: the Mitrokhin archive and the secret history of ... By Christopher Andrew, Vasili Mitrokhin" we have the answer:

"In February 1941 the NKVD cryptanalysts had been integrated into a new and enlarged Fifth (Cipher) Directorate, with at its heart a research section responsible for the attack on foreign codes and ciphers . . . In the summer of 1941 a group . . . replicated the success of American codebreakers a year earlier in breaking the main Japanese diplomatic cipher, codenamed by the Americans and since known to Western historians as PURPLE."

[this Fifth Directorate is a combined effort of the NKVD [secret police] and the GRU [military intelligence]? This is not entirely clear but seems to be the case!]

There is rather considerable significance to this. Prior to - - during - - and at the very end of the Second World War [WW2], the Soviets WERE able to "read" the most secret messages of the Japanese diplomatic corps, quite often that traffic dealing with military matters, AND especially in the aftermath of German surrender, the secret machinations of the Japanese to use the Soviets to arrange for a NEGOTIATED SURRENDER TO THE ALLIED FORCES [British and American]!

Stalin feigning cooperation with the Japanese, all the while preparing for Soviet entry into the war on the side of the allies, against Japan, typical duplicity of the dictator, aided and abetted to a large degree by PURPLE intelligence of the highest order and importance.

The record now crystal clear, the question answered, the full significance understood! 

coolbert.