Originally Posted by
Flying10uk
The point that you and others have missed is that, at the time of the Dieppe Raid, the allies/Bletchley Park were unable to decode Kriegsmarine Enigma codes because the Kriegsmarine had switched to the 4 rotor Enigma machine. This meant that instead of having the normal 3 rotors, the Kriegsmarine, had started using Enigma machines with 4 rotors and therefore Bletchley Park were unable to read Kriegsmarine messages encoded with the 4 rotor Enigma machine. A 3 rotor Enigma machine can communicate with a 4 rotor Enigma machine if the 4 rotor machine is properly configured so that only 3 of it's 4 rotors are in use, when in communication with a 3 rotor machine. Bletchley Park needed the information on the 4 rotor Enigma machine that was being used by the Kriegsmarine at the time of the Dieppe raid so that it could read Kriegsmarine messages.
The claim has been made that either the main purpose of the Dieppe raid was to steal the Enigma code material, specifically relating to the 4 rotor Enigma machine used by the Kriegsmarine, or that it was decided to "tack" this operation onto the main Dieppe raid.
Either way, I don't see that it is up to me or to anyone else using the Milserps forum, unless they were actually there, to either dismiss or to agree with/confirm the claim.
Personally, I can see the logic in hiding a "pinch raid" within a much bigger raid. As for the Germans noticing the Enigma material "missing", like I say, my understanding is that the intention of the Commandos was to demolish the building, holding the Enigma material, with explosives once the material was removed. I assume that more than one building would have been demolished for obvious reasons.