Voici la trascription d'une interrogation du General Schellenberg chef du bureau VI du RSHA en charge de l'espionage qui démontre que les ommunications de Dulles a Washington (y compris celle transmise) etaient decryptées par les nazis. Nous n'etions pas les seuls a faire du bon travail de decryptage:

Testimony of Walter Schellenberg taken at Nurnberg Germany, 13 February 1946 by Captain Horace Hahn, AUS, OUSCC.
Also present: Joseph Maier, Interpreter; and S. K. Saslaw, Court Reporter.

QUESTIONS BY CAPTAIN HAHN TO THE WITNESS THROUGH THE INTERPRETER:

Q: You are the same Walter Schellenberg who has been interrogated by representatives of the Office of Chief of Counsel previously, and you appreciate the fact that all statements which you make at the present time are under oath?

A: I do.
Q: Mr Schellenberg you were officially connected with Amt VI of the RSHA, I believe for a period of time you were the chief of that office: is that not correct?
A: Yes.
Q: The highest rank that you held in that position was Major General in the Waffen SS?
A: Yes.
Q: In your connection with that office what, if anything, do you know regarding the breaking of the diplomatic code which was used by the United States between Bern Switzerland and Washington in the year 1943?
A: I usually received the entire decodified material by the deciphering bureau of the OKW , Major General Thiele in charge.
Q: Is that the same Thiele that was connected with you at the board of directors of the Standard Electric Co.
A: Yes.
Q: And what type of code was used by the United States in this connection?
A: All that I know about the technical aspects, I do know from conversations with General Thiele. Now and then I had also conversations with a division chief of his, one colonel Kettler. The code that you asked about was, as far as I know, a deciphered diplomatic code. As far as I know, no mechanical was used but a very comprehensive written book code. We distinguished between technical codes and other codes. In my experience, it showed that technical codes were very difficult to decipher.
Q: You referred to the diplomatic code which was used by the United States as a technical code.
A: As far as I know it was not a technical code in this instance, but a normal book code.
Q: An ordinary code of given ciphers that were used opposite particular letters of the alphabet?
A: Yes.
Q: When was it that you first received from General Thiele a decoded message which had been intercepted between Bern and Washington. Do you recall that?
A: As far as I recall, it was in the beginning of 1943.
Q: Prior to that time, had your office or was it Thiele’s office that had been devoting its energies toward towards breaking the United States code?
A: Only the division of Thiele was concerned with the breaking or the deciphering of the code.
Q: Who was it under Thiele’s jurisdiction that was chiefly concerned; do you know?
A: That was colonel Kettler, and he had at his disposal a great number of scientists, mathematicians and other experts.
Q: On the base of his efforts toward breaking the United States code, did he ever comment to you whether he regarded it as a good code?
A: It was of interest to me that only the code between Bern and Washington was actually broken, not other codes that were in operation such as those between Cairo and Washington. I asked Thiele at one time how it came about and he told me that we owed the breaing of the Bern-Washington code to a lucky circumstance. He told me at that time that the Bern-Washington code was an ordinary book code and seemingly the other codes were mechanical.
Q: Did you ever have reason to suspect that perhaps the Bern-Washington code had been over-simplified by the United States in the hope that the German government would break it and thus be the recipient of distorted messages or of messages which it was hoped by the U.S. authorities they would intercept?
A: It was only later on that this idea occurred to me, but in 1943 and in 1944, I did not think of it in those terms, and that it may be over-simplified.
Q: The information which you intercepted as a result of breaking this code in 1943, did you find that information to be of interest or of any value to you in your office?
A: Yes.
Q: Do you remember any particular instances in which it was of particular value?
A: It gave an excellent survey of intelligence material at the disposal of Harriman about conditions in Germany. I remember that he had an excellent survey about the situation of the transport organization in Germany at that time, which he had relayed to Washington. Further about the steel and the coal production, the morale of the population, and also about problems concerning oppositional trends in Germany. Further, about the treatment of the churches, the effect of Anglo-American propaganda in Germany, suggestions as to improvements or changes in the directives of Anglo-American propaganda towards Germany, material bearing on Goebbels’ propaganda and suggestions as to how to combat it and to improve on counter propaganda; proposals concerning the reconstruction and renaissance of German literature after the defeat of Germany. Of particular interest, was an inquiry at one time by Secretary Hull concerning the person of Wirth, former German Reich chancellor, who resided in Switzerland at the time. I do recall the inquiry was very specified. It inquired about the personality of former Reich Chancellor Wirth, his place of residence, and the contacts he was having at the time.
Q: Did you find that these reports were relatively accurate that were transmitted?
A: It was obvious that Mr Harriman had excellent information about the conditions in Germany and his reports seemed to be very sound. On the other hand, his reports seemed to be based on information he obtained from economists who seemed less informed and tried to appear as important persons.
Q: That is, economists who were then residing in Switzerland?
A: These economists were apparently persons who, for business reasons, had left for Switzerland in order to establish contacts with other business people.
Q: Now, to get back for a moment to the code itself, I understand you to say that according to your classification of the code, you would regard it as a book code as contrasted with an ordinary technical code, and by technical code you mean a code, to decipher which you rely on mechanical means?
A: Yes
Q: Do you have any definite information as to the methods which were used in breaking the code by Thiele and this group of experts that was working under him?
A: All I can say about this is what I learned from conversations with Thiele. In order to break a normal book code, it was necessary to have a good many transmissions. If the technical procedure observed in several or many of the transmissions was the same, it was possible to break one particular spot in the code transmission and subsequently also to decipher the entire transmission.
Q: Was that the method which was utilized by Thiele in breaking this code that we have been talking about?
A: In this case I believe, yes, on the basis of mathematical probability.
Q: In other words to gain a more complete understanding of the methods which were used in breaking codes, perhaps it would be better to discuss the question with Thiele himself; would that be correct?
A: Thiele himself is no longer alive, you would have to talk to Kettler.
Q: When was it that you last heard from colonel Kettler?
A: In April 19454, when he tried to find out where I would finally go to, because he was anxious to keep in touch with me and my office.
Q: Have you heard any word of him since you have been taken prisoner by the Allies?
A: No
Q: It is correct, is it not, that he was a colonel in the Wehrmacht and was not a member of the Waffen SS?
A: Yes.
Q: Was he a member of the Allgemeine SS? Do you know?
A: I do not know.
Q: I believe it is correct, is it not, Mr Schellenberg, that you have been interrogated previously regarding this Bern-Washington code?
A: Yes.
Q: Where was that that you were interrogated?
A: I was first interrogated in Frankfurt after I had surrendered on June 17 1945 . Subsequently I was twice interrogated in London by English officers. Afterwards I was brought to London proper, where I was twice interrogated by a commission of a British chairman, a British specialist on deciphering and an American specialist on deciphering. Finally I was interrogated also in London with regard to deciphering in general, the OKW code and the research station.

Captain Hahn: That is all