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20 March 2013

NSA Assesses Winterbotham's "The Ultra Secret" (2.3MB)

NSA Cryptolog 15, VOL. II, NO. 12 DECEMBER 1975


DOCID 4009727






A PERSONAL COMMENT Brigadier John H. Tiltman


MUM'S STILL THE WORD! [redacted]



Declassified and Approved for Release by NSA on 10-11-2012 pursuant to E.O. 13526.

MDR Case # 54778



The following three articles deal in various ways with the publicity given in the British and American press and on television to F. W. Winterbotham's book "The Ultra Secret." The first article, by Brigadier John H. Tiltman, deals with the accuracy of the statements in the book and the degree of harm done by them. The second article, by P. W. Filby, is a review of the book as assessed by a member of the team of specialists who worked the German diplomatic problem. The third article, by [redacted] M542, a word of advice to those who might now be tempted to tell everything they know.


By Brigadier John H. Tiltman, P1

When Winterbotham's book was first published late in 1974 in England, some members of NSA who had served at Bletchley Park during World War II, on reading early reviews, assumed that it was officially authorised. This was definitely not the case. Its publication was strenuously opposed by British responsible authorities, who took legal advice on the probable consequences of prosecuting the author under the British Official Secrets Act. They were advised that prosecution could not be effective without the case going to court and evidence produced that British national security had been damaged by the book's publication with consequent public disclosure of more current intelligence activities. They therefore decided that legal action would probably do more harm than good.

Another and perhaps a decisive factor making prosecution unlikely to succeed was the publication in France in 1973 of Bertrand's book Enigma, ou La Plus Grande Enigme de la Guerre 1939-1945. This revealed for the first time the fact of an analytic success against the Enigma and was decisive in the discussions between Deputy Director NSA and Director GCHQ on the matter of whether to attempt to restrain Winterbotham and his publisher.

I am not alone in believing that an early official public description (perhaps a joint US-UK statement) of the basic facts of the wartime exploitation of the intelligence derived from the solution of the Enigma keys might have mitigated the damage done to security. Perhaps this could have been strengthened by a further

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statement that the revelation of technical details of the methods of solution would be resisted indefinitely. I realise however that there must be other valid arguments which persuaded the responsible authorities not to take such action.

I myself took no part in the solution of Enigma keys in Huts 6 and 8, nor in its exploitation in Hut 3, but I am, I believe, the only person around who was on the directorate level at Bletchley Park during the war and had a hand in many of the policy decisions made regarding the production and use of the intelligence derived.

The book is poorly written and very inaccurate in some areas where I know the facts. The references to the early history of Enigma solution and to the activities of the staff of Hut 6 (who performed the cryptanalytic part of the enterprise) are hopelessly wrong. It is difficult to understand how the author who had considerable responsibilities for the organisation and distribution of Enigma intelligence could have been so completely ignorant of the technical side of the operation. He doesn't know the difference between the Enigma (a rotor machine), other German ciphers, the Japanese high-grade diplomatic machine (the "Purple," a totally different kind of machine), and the Japanese Fleet general cipher (a codebook and additive hand system). His remarks about the "Bronze Goddess" appear to be a complete invention.

Some people gather the impression when they read the book that the author greatly magnifies his own part in the winning of the war. I give an example from my own experience. To quote some passages, "It was at this point that Menzies told me he had decided to hand over my shadow OKW in Hut 3 to the General Administration at Bletchley. One never knew where one stood with Menzies. He softened the pill by confirming me as his deputy ... " (p. 87). "Despite the loss of my personal control of Hut 3 and the shadow OKW, I still had direct access to it when required. I was never told by Menzies the real reasons for the takeover ... "(p. 92). The facts are that I reported to the Director of Military Intelligence at the War Office, that Curtis, the War Office representative in Hut 3, in conjunction with Humphries, the corresponding Air Force representative, had on two separate occasions gone behind my back to recommend reorganisation of Hut 3 under their own more direct control. In consequence, a SIGINT Board meeting was called with General Menzies in the chair and consisting of the three Service Directors of Intelligence and Director GCHQ. At this meeting it was decided to withdraw Humphries, Curtis, and the naval representative.

I knew Winterbotham slightly and flew with him to Paris on the occasion of one of my official visits to France in 1940. His outstanding achievement was the establishment of SLUs (special liaison units) for the dissemination of ULTRA to commanders in the field. I have no reason to doubt that he records this faithfully. He gives rise to feelings of dscomfort, however, when he describes his relations with the more high-ranking recipients of his wares. It appears that Montgomery must have treated him with less courtesy than others and consequently he feels sure he himself could have fought Montgomery's battles far more efficiently!

In view of its general inaccuracy, especially when touching on technical matters, I believe the book, taken by itself, does no harm. This cannot be said for the side effects it touched off. The first review I read was in the Washington Post by Al Friendly, who himself served in Hut 3. He headlines his review "Confessions of a Codebreaker." He gives the impression that for a great part of the war every telegraphic order issued by Hitler was currently on the desk of the Prime Minister and concerned Allied commanders. This is simply not true. Such a picture takes no account of the many difficulties of the operation, the decisions to be taken on insufficient evidence as to priorities of attack on some keys to the exclusion of others, the many failures and delays, the early misunderstanding as to the real meaning of messages, etc. The general success of the project was as much a triumph of organisation of the large-scale attack as of the ingenuity and persistence of the cryptanalysts, especially the mathematicians.

Perhaps the most objectionable of the reviews was a long article in one of the London Sunday newspapers by Peter Calvocoressi. He was an important figure in Hut 3, presumably recruited by Winterbotham. He is now, I believe, managing director of Penguin Books and was the joint author of a distinguished history of World War II. His article is an extremely well-written description of life in Hut 3, but he has gone further than anyone else in including a photograph of the German Service Enigma and in mentioning the Bombe. I believe this was the first time a picture of the service Enigma appeared in public print. Not even Bertrand in his book Enigma gives a photograph of the machine. I am quite unable to understand Calvocoressi's arrogant assumption that he can say what he likes in public now that Winterbotham's book has appeared. I hold the view that everyone who worked in Bletchley Park is still under a moral obligation not to disclose secrets not previously published without official permission and, I would have thought, is aware of this obligation.

Many of us were nervous of what David Kahn would have to say when his turn came to review the book. When his review did appear in the New York Review of Books, it was surprisingly mild and harmless. He, of course, is in a different category. Not ever having been a part of

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any Government agency, he cannot be regarded as subject to the same restrictions.

Other reviewers have been influential journalists who have taken the tone that the book has revealed the operations of World War II in a new light, that history will have to be rewritten, that the British have told only part of the story and that they will have to tell the rest. I do not know whether we have heard the last of this attitude.

Something has to be said about the paragraphs on page 14 of the book dealing with personalities. Winterbotham mentions the mathematicians Alexander, Babbage, Welchman, and Milner Barry, but doesn't seem to have heard of Turing, who is generally regarded as the leading genius of the methods of solution of the Enigma in its various forms. He says that "it was generally accepted that of our own backroom boys 'Dilly' Knox was the mastermind behind the Enigma affair." I do not agree with this at all, though I am aware that he was in general charge of the analysis of the machine before the war and long before the British had any success in solution. Incidentally, Winterbotham seems to confuse Knox with Foss, who fits much better into the physical description in the book and who had some influence mbes became available. In his casual remarks about me, Winterbotham is somewhere near the truth: he says I had been borrowed from the Army. So I was -- 20 years earlier! Of Josh Cooper he says he was "another brilliant mathematician." Josh wasn't a mathematician at all -- he was a very fine linguist. For no known reason, Winterbotham mentions Dick Pritchard. He was a regular Army officer who had been with me for 8 or 9 years, before the war, but he had nothing whatever to do with the solution of the Enigma.

I think it quite likely that all this does no harm at all, but we cannot by any means be certain of this. Therefore, we have to continue to try to withhold further disclosures, particularly on technical methods of solution.


Briigadier Tiltman was Deputy Director and Chief Cryptographer, GCHQ, from 1941 to 1946. Since 1964 he has been working at NSA, Fort Meade. He is a Commander, Order of St. Michael and St. George; Commander, Order of the British Empire; and Distinguished Member, CMI.





By P. W. Filby

Shortly after the outbreak of World War II, the British Government acquired a stately home in a small town called Bletchley, a town renowned only for its railway junction and nearby brickyards. For the next few months civilians and servicemen and women arrived in ever increasing numbers, and hardly a house in Bletchley escaped billeting. The citizens wondered at the motley crowd, raffishly dressed for the most part, often absent-minded and all having a studious air about them.

High iron fences were erected round the home known as Bletchley Park and armed Army guards were on duty at all times. The locals had to get used to comings and goings of their lodgers at all hours, and having taken in civilians they would suddenly see them emerge in full regalia as officers of the three services, especially when they made trips to London.

Many guesses were hazarded but the only thing that could be said was that it was a secret department -- and the secret was well kept, so well that it is not until now, thirty years later, that the Bletchley people and the world will know that the many thousands of people at the "Park" were working in enemy codes and ciphers.

Group Captain Winterbotham has taken advantage of the "30-year rule" to describe the success of one group, "Hut 3." It is an absorbing story, and although the chief defect is that Winterbotham was not a codebreaker and therefore makes several wrong assertions, the book is one of outstanding interest, and readers will marvel at the war's greatest secret and how it was kept until now.

Just before the outbreak of World War II the British had obtained by various means a complex machine known as "Enigma" which was being used for the encoding of the most secret and important German armed forces communications . After a prodigious effort the British cryptographers of "Hut 3" managed to break this machine and later built what might well have been the first computer, so that the communications could be read immediately upon receipt.

To everyone's surprise, the Germans continued to use this machine throughout the war and thus most plans made by Hitler and his High Command were known to the British (and later, the Americans also) at the same time as the German recipients.

Radio operators in remote, lonely locations intercepted the messages, which were rushed to

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Bletchley, often by motorcycle until more sophisticated methods were evolved, and were promptly decoded and passed to the appropriate commands. The intelligence was code-named "Ultra."

Astonishingly, there is nothing in captured German documents to suggest that anyone sus pected that the most secret cypher code was being read throughout the war. Much of the credit for this were the rules laid down by Winterbotham for the "need to know."

For instance, the Russians were never told of it, and the many free forces (French, Dutch, etc.) were not let in on the secret. Winterbotham toured British and American commands, lecturing users on this intelligence and warning them care had to be taken on how the information could be used.

For instance, although the presence of an enemy force might be given in detail by Ultra, to bomb it immediately would cause the Germans to wonder how the enemy knew of this force, so reconnaissance planes had to be used so that the Germans would suspect that they had been spotted from the air.

Unhappily, it was not unusual for holders of the German plans to have to forgo using them for fear of compromising the cypher break. One such occasion was the bombing of poor Coventry; enemy plans were known beforehand, but to defend the city would have aroused German suspicions. Although attempts to defend were made, the populace was not warned in advance. At that time it was not known whether German spies were working among the British.

But the information was used with telling effect in the Battle of Britain, when the Air Force knew exactly the direction and the force to be employed in each attack. It is probable that Ultra did much to save Britain in those dark days. Everyone knew the Air Force could not withstand these onslaughts for long, but Ultra allowed them breathing space by parceling out the slender defense forces where needed most.

Ultra played a particularly distinguished part in the North African campaign, where Montgomery was informed of Rommel's disposition of his forces and the extent of his supplies. Ultra also enabled supplies across the Mediterranean Sea to be sunk en route. Montgomery's face should be red, since he claimed verbally and in his books that he planned his battle order, but he acquired the record of invincibility only through his use of the information given by Ultra.

With the British losing thousands of tons of shipping weekly, the decoding of the German Navy's messages provided a welcome respite, and from 1943 the losses were significantly reduced since the disposition of the U-boats was known.

One wonders now just how the Normandy landing would have worked out without Ultra. Since decoded messages told of the German belief that the attack would come from the narrow Pas de Calais, General Patton arrived with a phantom army to give the impression the landing would indeed be tried there. Consequently Rundstedt and a vast army were kept there, reducing the defenses in Normandy.

Ultra's strength was also shown when, in the Battle of the Bulge, the Germans relied on telephone rather than radio communications, and many lives were lost because the Allies could 1earn nothing of the German plans and intentions.

These and other exciting stories are related in this absorbing book. It suffers perhaps because Winterbotham was a "go-between" rather than one of the codebreakers, and thus credit is not given to the mathematicians and linguists who worked long hours in stuffy rooms where, because of blackout precautions, fresh air seldom penetrated the smoke-filled atmosphere.

Tribute, must also have been paid to those radio operators, straining their ears when static and other conditions meant a missed group and maybe an important one at that, when the operator could not ask for a repeat -- these were the real heroes of one of the outstanding accomplishments of the war .

One amusing tailpiece to the whole affair is the effect it will have on those whose memoirs have already been written. Many should now be rewritten; if Ultra did not actually win the war it will cause historians to revise what has been written thus far. Books such as "D-Day" are exciting reading, but the present work must be included in all war hiptory collections from now on, since it will affect all war histories in varying ways.

Winterbotham is rightly proud of Bletchley's achievement, but he tends to forget that information, needs acting upon; it needs good generals and above all a great Air Force, Army, and Navy. Fortunately the Allies had these too, and though Ultra was one of the most important contributions to the victory, Winterbotham perhaps overrates it a little.

Sir John Masterman's book, "The Double-Cross System in the War of 1939-1945" (reviewed in these columns February 12, 1972) describes how captured spies were "turned around" and also contributed to the downfall of Germany. There were other great coups but UItra and Double Cross must rank very high in the defeat of the Nazis.

P. W. Filby, in addition to his SIGINT experience at Bletchley Park and GCHQ, is an "honorary NSA-er by marriage" (his wife is CLA President and CRYPTOLOG's SRA Editor Vera R. Filby). Mr. Filby is the current Director of the Maryland Historial Society, Baltimore, Maryland. The preceding review is reprinted in entirety from the Baltimore Evening Sun, June 10, 1975. FOUO

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Many people make their work and the organization they work for an extension of their own egos, especially when the organization is performing a vital service to society. For most people, one of the most compelling motivations on the job is the quest for approval by their peers and supervisors. But we NSAers are not like "most people." True, we have always been able to rely on peer and supervisory approval, but we have never been able to derive ego gratification from identifying with NSA -- historically, both the Agency itself and our specific jobs here have been obscured from public notice. Lately, however, the curtain cloaking our activities has been lifted slightly. Winterbotham's book The Ultra Secret and the follow-on revelations in the CBS television program, "Sixty Minutes, " have provided the public with glimpses of the vital role that cryptology plays in protecting our nation's security. Certainly, all of us must feel a sense of pride, and perhaps indulge our egos a bit, to see our Agency's vital function finally made known to the public. It's a very seductive thing. We plug along for years without public recognition. We strive constantly to overcome the natural urge to discuss our work with non-NSA friends, particularly when that work involves events taking place on the world stage. Then, suddenly, there's our organization, our work -- us! --on the television screen, the front page of the newspaper, the public bookshelf. How easy it is to feel proud about finally getting public recognition. But that initial feeling of pride and personal gratification is soon outweighed by the disquieting realization that someone has talked, someone has betrayed our tradition of keeping our mouths shut.

The fact that such revelations do not always compromise sensitive information, as in the case of The Ultra Secret and the TV follow-on, does not diminish our feelings of dismay. That precious shell of anonymity -- so carefully maintained over the years -- has been cracked. One can only expect that others will rush forth to give their versions of past events and open that crack still wider.

That our cryptologic operations are discussed at all in the public media, no matter how many decades have elapsed, is the primary concern here. Journalistic appetite begets appetite and, once titillated by the morsels served up by disclosures such as those in Winterbotham's book, it tends to become ravenous for the whole pot. Those who were associated with the cryptologic effort in the past -- and the numbers are prodigious -- as well as those currently involved, are presented with a psychological cop-out to indulge thelr ego [redacted] talk about their work. After all, everyone else is doing it. Thus, revelation begets revelation.

The publication of The Ultra Secret, however innocuous its specific revelations, can only be viewed with foreboding. It can only hasten the dropping of the next shoe. And when that shoe drops, we NSAers should remember, "Mum's still the word!"

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