Ultra/Enigma I.

This is coolbert:

Without a knowledge of the Ultra secret, one cannot be conversant and knowledgeable in the history of the Second World War [WW2].

Ultra. The intercept, the decryption, the analysis of supposedly “secure” German military radio traffic during the war. A process that produced ACTIONABLE intelligence the allied forces could and did use to their advantage.

"By 1943, a large proportion of intercepts (over 2,000 daily at the height of operations) were routinely read, including some from Hitler himself. Such information enabled the Allies to maintain an often remarkably accurate picture of enemy plans and orders of battle, and, when appropriately used, was of great value in formulating Allied strategy and tactics."

[primarily of military encrypted radio traffic, but not confined exclusively to the military.]

German “secure” radio traffic encrypted using the military version of the ENIGMA cryptographic machine. An electro-mechanical apparatus that unbeknownst to the German was NOT secure. Read with impunity by the British and Americans, before them by the Poles, and sparingly by the French.

Considered to be a war winning weapon. NOT a weapon in a literal sense. A figurative sense. Allowed the allies to know where and when to apply military force to gain the best results. Shortened the war and enabled allied victory by TWO YEARS??!!

"but a typical assessment is that the end of the European war was hastened by two years because of the decryption of German ciphers."

It should also not be forgotten that the "reading" of the Japanese "Purple" crypto machine also contributed significantly to the victory in Europe and also hastened the end of the war in the Pacific too:

"Some Purple decrypts proved useful elsewhere, for instance detailed reports by Japan's ambassador to Germany which were encrypted on the Purple machine. These reports included reviews of German strategy and intentions, reports on direct inspections (in one case, of Normandy beach defenses) by the ambassador, and reports of long interviews with Hitler."

"Baron Oshima, who was a military man, avidly studied German military developments and deployments and reported on them at length back to Tokyo via PURPLE-enciphered messages sent via radio. A good example of this was that he reported on the emplacement of the Atlantic Wall fortifications that the German Wehrmacht was building along the coasts of France and Belgium. Thus, unbeknown to either the Germans or the Japanese, he was reporting to the Allies much about German military preparations against the forthcoming D-Day invasion of Western Europe."

Ultra obtained through the reading of Enigma can be thought more of providing intelligence of a “nuts and bolts”, “bread and butter”, “beans and bullets variety”. Crucial day-to-day intelligence supporting the Allied combat commander.

Think of “Purple” as being also of crucial value, but regarding long-term, strategic and geo-political thinking of the Axis leadership. NOT normally found in Engima traffic. Those Japanese military attaches’ from all over Europe, without even realizing it, contributed significantly to the defeat of the German and the other Axis aligned powers.

NOT until the mid-1970’s was the Ultra secret declassified so that it became public knowledge.

[The historian/biographer David Irving and the novelist Herman Wouk both apparently stumbled upon the Ultra secret during their researches!!]

Perhaps the best book, short but to the point, describing the entire Ultra story, without confusing descriptions of cryptology, is the book, “Top Secret Ultra”, by Peter Calvocoressi. Dated now, but still very good. I recommend.

Go here to see an outstanding graphical simulation of the Enigma machine. Everything is quite clear and made apparent. The plugboard [stecker], the three rotors, the reflector, the connections and rotations as the machine steps through the encryption process. Type with you computer keyboard the plaintext where the “input” is shown, and below you will see the ciphertext. Same as actual machine would work!

[when you go to the Enigma simulation site, click on the yellowish box with the gears in the center of the web page to access the graphics.]

Try this too. Repeatedly enter the letter “A” [or any other letter for than matter] at the input as many times as you want and observe the output [the ciphertext]. If using “A” in the input stutter group [AAAAAAAA . . .] you will NEVER see “A” in the cipher text output, NO MATTER HOW LONG THAT STUTTER GROUP!! This is a WEAKNESS of the Enigma. Keep this in mind.

"no letter of the alphabet could ever be enciphered as itself. Z might turn into any letter from A to Y but never did it become Z."

coolbert.