Records and Memory

 

One of the more interesting questions I had to answer as GCHQ historian was why a large collection of intercepted message logs encrypted in the JAGUAR key (used by the Luftwaffe) from the period after D-Day had been retained. These logs once analysed have no value (because any value they have has been realised through the analysis), and were normally kept for a few months ‘just in case’ before being disposed of.

This batch, however had been kept so that a serious TA (traffic analysis) study could be made of Luftwaffe communications before the Ardennes Offensive. How the pattern of communications activity had changed as the German retreat continued, and how German preparations for an offensive had been misinterpreted, or at least not recognised, was an important piece of retrospective analysis as it would provide an indicator or warning of preparations for an offensive in future conflicts.

More on the results of analysis of Luftwaffe communications another day, but for now I want to focus on the difference between what those involved wrote about German Army intercept during the period before the Offensive in the summer of 1945 in The Sixta History (HW 43/82-94), seven or eight months after the event; what one of the authors wrote 40 years later from memory, though after discussion with former colleagues and reading the first of the works about Second World War Sigint; what Ralph Bennett, who had reported the material which was released by the MOD in the 1970s, and what Hinsley’s Official History says.

This isn’t about intelligence and the Ardennes Offensive except insofar as they provide a hook on which to hang a few thoughts about records and memory, and the perils of relying on either without more context than most writers on British Sigint in the Second World War can access.

I start with the relevant extract from The Sixta History: this is ‘deep analysis’ by the people who had worked this material day in, day out, and typical of much of the intelligence activity of a Sigint organisation; it might be hard to understand to those not steeped in it. Remember that Sigint analysts can’t ask their targets why they have changed the way they work, and have to look at information they are able to get about their targets’ operational activity to map back to the way they communicated, and thus identify potential indicators and warnings.  For example, a day’s radio silence in the German Army was identified on two occasions in October and November 1944 as being related to the move of a formation to a new location.

(In this extract ‘star’ refers to a communications network consisting of a ‘control’ and two or more ‘outstations’ which may or may not be allowed to work ‘laterally’ to one another. This was on the whole the most common communications structure as it corresponded most closely to the shape of order-of-battle subordination.)

‘German Army

Activity before and during the Ardennes Offensive.

It will be of interest to compare the W/T activity shortly after D day (described in Section 5) with activity before and during the Ardennes offensive, which was launched on Dec 16, 1944. Activity in the west generally had been very low in October and November, 1944, and it was obviously the policy of O.B. West at the time to restrict W/T communication to a minimum. A wireless silence had been ordered for the area of H.Gr.G on Oct. 13 for the transfer of Pz. A.O.K.5. and for certain static units of O.B.West on Nov. 9. The latter order may in fact have applied to all forward W/T links in the west for activity on the L/F Netz was extremely low from Nov. 6 (only one message was passed on 9th) and continued low throughout November and December. Similarly, two of the main stars of H.Gr.B (Beta 4S – operational and Beta 5S - supply) ceased activity about this time. 5S was active until Nov.7 and 4S until Nov.10.

A reference to Diagram 3 (Supplement 10), however, shows that from about Nov. 15. one of the operational stars of H.Gr.B (Beta 4S-) resumed activity and that by the end of the month the supply star (Beta 5S) and two other operational stars (Beta 7S and 8S) were also active. Beta 7S was in fact first identified on Dec.1.  In addition a new star of Panzer A.O.K. 6 (G2S) appeared on Nov. 28. In view of later events it can only he assumed that H.Gr.B was then trying out its new W/T links, based on a new Funkplan in preparation for the coming offensive. Thus although the forward L/F Netz was almost inactive prior to the offensive, links back from army were rather more active than usual. From a long-term point of view, however, the low activity generally in October and November and the wireless silences ordered were to some extent an indication that the Germans wished to conceal their future plans.

It is worth noting here that, owing to the low volume of traffic in November, Bantam, the main Enigma key in the west, was broken on only 3 occasions, and there was thus no indication from Army decodes of the coming offensive. It is clear that the intelligence staffs finally responsible for advising commands in the light of decode information should be aware of any gaps in W/T activity or cryptographic success, which might affect the completeness of their information.’

To summarise, those involved in network analysis recognised that something significant was going on, and recognised that the wireless ‘silence’ (more accurately a ‘communications minimise’) was indicative of a least a relocation of units. They also realised that intelligence staff should have made the Commands aware that something was happening with the Germans’ comms. There’s an element of ‘Not me, guv’ to this: traffic analysts were at the bottom of the pile and information flowed upwards. ‘someone’

Forty years after the event, Neil Webster, one of the authors of The Sixta History who had worked in the Fusion Centre, the point at which decrypted messages and TA were brought together before being sent to Hut 3 intelligence analysts for reporting (and with no access to the surviving records of) wrote (in Cribs for Victory, published in 2011 but written by 1984:

‘It was December 1944 and the German armies appeared to be in full retreat, when Rushworth and I read a message setting up a new 'star' on which were all the armoured divisions, including some transferred from the Russian front. They were given orders to maintain wireless silence apart from occasional calling and keying to keep in touch, keying that should never go on long enough for a bearing on the station to be taken. They did just that. The intercept stations were told to listen on the announced frequency and they picked up the announced call signs and a little keying at intervals but nothing else. At a meeting of officers of our unit, we considered whether to tell Hut 3 that this looked rather like preparation for a counter offensive. I was all for telling but the meeting decided not to for the rather poor reason that it would make a big fuss and we would look silly if we were wrong. A few days later came the Ardennes offensive for which the Allies were unprepared.

I talked about this later with Peter Calvocoressi, the head of Air Intelligence section in Hut 3, and he told me not to feel too badly about it, as Hut 3 already suspected from increases in railway traffic and other indications. Then why did not Supreme Headquarters Allied Expeditionary Force know? I asked, Peter explained that Hut 3 was shy of going beyond its job of amending and explaining German messages. Drawing broad conclusions was for the intelligence staff at SHAEF, who had information from all sources. So Hut 3 did not tell SHAEF of the conclusions they were beginning to draw and SHAEF did not draw any conclusions, as is clear from Winterbotham's book The Ultra Secret, where he states there was no evidence of the enemy offensive from Bletchley or anywhere else.

Peter Calvocoressi, in his book Top Secret Ultra, gives a different account, quoting the story of the announcement of the new network as an example of valuable radio intelligence, as if I had actually told him in time. I'm sure I should have, even though it was not my job. I knew him and I should have told him the facts and asked his opinion. But at the time I didn't. Nor, I think, can Bax or Malabre [Rodney Bax and Basil Malabre were fellow army officers in Sixta] have commented on the message announcement as this would have been enough to put Winterbotham's staff on their guard. I still feel badly about it. It was so unlike Bletchley. And it cost lives.’

Each of these messages has a very different tone. The first is very matter of fact: it tells a story of low levels of activity (and therefore of cryptanalytic breaks) and an understanding that radio silence could be evidence of the relocation of a unit. (Later on, the fact that the closer they were to the German border, the more the German Army could take advantage of a landline network, which meant they didn’t need to use their radios as much.) The extract focuses on the need to ensure that levels of activity, and levels of cryptanalytic success are part of the Sigint story that should be sent to intelligence officers to give necessary context to the information they are giving to Commands about enemy activity.

Webster’s description is more dramatic: a meeting that interpreted the minimal intercept as probably part of the preparation for a counter-offensive, and the decision not to tell Hut 3 because it was the absence of activity that was the evidence for such an interpretation; Hut 3 having drawn similar conclusions from other indicators but not telling SHAEF, because it was SHAEF’s job to do the all-source analysis, not Bletchley’s. Webster also makes a value judgement – ‘It was so unlike Bletchley. And it cost lives’ – that is difficult to accept at face value. Interpretation of the intelligence it produced was not particularly welcome either in the Intelligence Divisions of the Service Ministries or those of the Commands.

Ralph Bennett sets out his stall as a commentator when, in Ultra in the West, he writes:

‘It is unusual to have the opportunity, when young, of sharing in the creation of an archive and then to be able to use it in later life for the purpose of historical research. I am conscious of my good fortune, but also of the hazards it brings. Writing 'from the inside', I have the advantage of knowing exactly how Ultra was handled. Re-reading the 1944-5 signals, although after so long an interval, has even brought back surprisingly vivid recollections of the particular circumstances in which some of the thousands which bear my initials were drafted. But this advantage has demanded the counterbalance of a deliberate will to write objectively; I have tried, for instance, to be as quick to point out what Ultra did not or could not do as to draw attention to its triumphs. It has also enlarged the historian's familiar problem, the avoidance of hindsight, not least because in this instance it has an unfamiliar twist.

Hut 3's job was to process with meticulous care a stream of intelligence items as they came in, and to publish them, under appropriate safeguards, to those who could use them. Our function was to elucidate each item, not to access the broad significance of them all or to issue periodical commentaries upon the intelligence as a whole. It was not for us to write position papers or propose action, scarcely even to suggest that a certain interpretation might be placed upon a number of apparently unrelated items if they were viewed together in a particular light, unless the reason for doing so derived from our specialized technical knowledge. These things were the province of command staffs and service ministries; we were neither an operational headquarters nor an aloof body of strategists. But since we did not issue appreciations or forecasts, we could hardly make mistakes on the grand scale, although we might err in translating or interpreting single items. There is nothing, for instance, to record what Hut 3 thought at the time about the evidence for an offensive in the Ardennes assembled in chapter 7, or even that it had a collective opinion at all. Awareness of this immunity from past error has made me very cautious before expressing my conviction that the field commanders more than once seriously mistook the true meaning of the Ultra intelligence with which we supplied them.’

I don’t think this will do. For a start, Bennett was working solely on the Hut 3 material released to TNA in DEFE 3 and had no access to other intelligence sources (either in 1944 or in 1978-79 when he was writing his book), and, anyway, had no experience of all-source of multi-source analysis assessment. Furthermore, as he notes in a 1983 letter to Webster reproduced in Cribs for Victory, he had forgotten that TA’s two primary tasks lay in driving collection resources to produce the cribs which would allow cryptanalysts to discover that day’s keys, and in providing the information about comms usage which would mean that stations could be tasked as productively as possible. Bennett has written a partial account, one which in this context is designed to show that Hut 3 produced valuable and relevant intelligence that the Allied Commands should have interpreted as preparations for a large-scale German offensive in the Ardennes.

Hinsley’s account is more nuanced than Bennett’s. It shows that the all-source analysts in the Commands were working with limited amounts of material from sources other than Ultra, that some of the messages were only decrypted days after they had been sent and intercepted, and cites one report which BP didn’t circulate as having been important, but decides, if far less trenchantly than Bennett, that the Allies should have done better.

These four examples show how easy it is even for people who were at Bletchley during the Second World War not to interpret BP’s records authoritatively. Neither Bennett nor Hinsley were traffic analysts (and even if Hinsley and his researchers had had access to The Sixta History it is very likely that they would have concluded that what it described was ‘in the noise’ rather than a clear contribution to intelligence). Without understanding the context in which intelligence was created and disseminated, it is hard to write something that doesn’t look like special pleading.

Underlying this are two aspects of BP that I have talked about before: first, that thoughtlessly applied ‘need-to-know’ can be a pernicious drag on any intelligence organisation as it stops analysts from understanding completely exactly what the link in the chain prior to theirs actually means; and second, that the various snobberies in the organisation (for example that cryptanalyst were somehow ‘better’ than any other analysts, or that graduates – especially Oxbridge graduates – were intellectually superior to non-graduates) hampered intelligence production: perhaps as much as need-to-know.

Each of these four works is valuable but were for different audiences. The Sixta History is a detailed account of how first information, and subsequently intelligence came to be derived from study of the way in which the German Army and Air Force used wireless telegraphy for their communications. It is dense and demands at least a basic understanding of radio communications network: it was written by traffic analysts as a guide for future traffic analysts. Cribs for Victory tells the story of how the people who developed this analytical technique did so, but focuses on the people. Bennett is the first person to show exactly how Ultra illuminated enemy operations and intentions. Hinsley (and his people) looked beyond Ultra to the whole of British Intelligence, and addressed the big picture rather than trying to analyse tens – perhaps hundreds – of thousands of individual reports.

I have an extra level of interest in the issues arising from this: This story interests me for several reasons: I managed the release processes for both Cribs for Victory and The Sixta History; I am an advocate for TA’s being recognised as a discipline as important as cryptanalysis in Sigint; I want to see better informed works recounting British Sigint history; and I like dispelling myths. Now that practically all of the relevant Sigint material surviving from the Second World War has been released, it is time to look again at the way that the material from GC&CS was prepared, disseminated and used. There is a long way to go!