GCHQ

No cypher system, Chitty warned, was unbreakable. Britain’s most sensitive material was sent by one-time pads, which were, in his opinion, ‘unassailable’ if used correctly. Yet he reminded his superiors that Bletchley was making a ‘most successful daily attack’ on the one-time pads of other countries, ‘which reach us in a steady stream by Photography, Theft, and the sifting of Embassy waste-paper baskets’. The majority of London government traffic went by Typex machine, the British equivalent of Enigma. This was much better than Enigma, but Chitty asserted that its security had never really been tested. Again, much depended on the diligence of the operators:

One of the most instructive lessons I learnt from the [Government Code and Cypher] School was the fact that the Hagelin machine used by several nations including the Americans, affords in practice a widely different degree of security in different hands. Whereas this machine, as used by the Swedes and the Finns, has so far been virtually unbreakable, in the hands of the Italians who are normally very good cryptographers, we have for a long time been able to read it with ease. This was entirely due to the increasing idleness of the Italian operators and their persistent disregard of the numerous security rules which have been laid down for them.

For routine traffic the Foreign Office used more elderly hand cyphers, and the services made use of field cyphers in their lower formations. Quite rightly, these were thought to be even less secure.[28]

By March 1944, no less a figure than Winston Churchill himself was calling for a shake-up. A new supervisory outfit was created, called the Cypher Policy Board. Although Menzies was in the chair, Edward Travis from GC&CS, together with the Secretary of the War Cabinet and a representative of the Chiefs of Staff were also there to keep a stern eye on him. This top-level representation underlined a deep anxiety about cypher security. A new Deputy Director of GC&CS, known as the Communications Security Adviser, was also to be appointed, who would serve as the Secretary of the Cypher Policy Board. In reality, this person, Captain Edmund Wilson, was the new broom.[29] After the war, Wilson was replaced by Commander T.R.W. Burton-Miller, who operated from a new headquarters at 10 Chesterfield Street W1, conveniently close to both MI5 and SIS.[30] Soon they had extended their authority over the design and production of all British cypher machines, with Gordon Welchman their chief technical adviser.[31]

During 1944, Bletchley Park offered an impressive technical solution to worries about cypher security. It fielded a new and rather superior cypher machine called ‘Rockex I’ that produced what was effectively automated one-time pad traffic. Instead of using tiresome tear-off sheets from a one-time pad that had to be processed by hand, it used code tape, which carried the same information. This was initially used for messages between Bletchley Park and its sigint collaborators in Washington and Ottawa, together with the SIS wartime office in New York. A new version called ‘Rockex II’ was already being developed by the British. The machine was originally intended for the Special Communications Units that disseminated Ultra to Allied commanders in the field, but after the war it became a mainstream British cypher machine, and was still being used by smaller embassies in the 1970s.[32]

The super-secret Rockex cypher machine also had another purpose. From 1944, it provided extra security for the communications network of Britain’s SIS agents around the world. With assistance from Bletchley Park, wartime SIS had been able to develop an effective long-range wireless network to support its overseas stations and agents in the field. Known as SIS Section VIII, this was run by Brigadier Richard Gambier-Parry from two country houses not far from Bletchley, at Whaddon Hall and Hanslope Park. These locations not only provided a wireless network for SIS, they also built covert radio sets hidden in suitcases used by British agents and fitted out vehicles for the Special Liaison Units that supplied sigint to overseas commands such as Montgomery’s Eighth Army. In addition, Hanslope Park had provided a base for a unit called the Radio Security Service, under Ted Maltby, that had used mobile detection vans to track the radio transmissions of enemy agents hiding in wartime Britain. SIS was a small organisation with small volumes of radio traffic, and up until 1944 it had been comfortable sending its traffic by slow but highly secure one-time pads. The Rockex machine allowed it to take a leap forward.[33]

By 1944, SIS’s Section VIII had expanded considerably and was taking on new customers. With its new Rockex machines, it was carrying some traffic for Bletchley Park, typically from Canada, together with secret messages for the Special Operations Executive which conducted sabotage. The Foreign Office was now looking at this efficient radio network with growing interest, and at the end of the war SIS Section VIII was simply coopted to form the backbone of a new Foreign Office communications system called the Diplomatic Wireless Service. Gambier-Parry became the first Foreign Office Director of Communications. As early as 1943 some embassies, such as that in Cairo, had been switching over to ‘experimental use of official wireless’ by making use of local SIS facilities.[34] Although diplomatic wireless was technically banned by international diplomatic convention, in practice cable communications had frequently been disrupted during the war, and wireless had crept into widespread use as an alternative.[35]

The gradual development of the Diplomatic Wireless Service at Hanslope Park during 1944 and 1945 was another critical building block in the creation of the modern British sigint community. Alongside the military sigint collection stations in locations such as Ceylon, the Diplomatic Wireless Service, or ‘DWS’, doubled as a secret monitoring service working from within British Embassies and High Commissions. The first permanent undercover sigint station was set up at Ankara in 1943. DWS staff numbered close to a thousand, and about half its time was devoted to secret collection on behalf of the British code-breakers. Over the years it produced important results from locations as far afield as Moscow and Luanda because of its ability to collect short-range transmissions.

In August 1945 the Second World War finally drew to a close. Winston Churchill was of the view that Bletchley Park was the deciding factor in the defeat of the Fascist powers: in 1945 he apparently told King George VI that Ultra had effectively won the war.[36] Robert Harris, author of the novel Enigma (1995), rightly points out that most of the major combatants had military forces that were superior to those of Britain, not least in their weapons technology. Bletchley Park was the one place where we enjoyed a crucial world lead.[37] Harry Hinsley, a junior figure at Bletchley Park, but later the official historian who produced a magisterial study of intelligence during the Second World War, has famously asserted that Ultra shortened the war by several years, saving countless lives on all sides. Without Ultra, he states, ‘Overlord would have had to be delayed until 1946’.[38] Andreas Hillgruber, the distinguished German historian of Hitler’s strategy agrees, adding that as a result the Soviets might well have advanced much further west.[39]

Yet others, including the British historian Paul Kennedy, have argued that the Second World War was largely a battle of material production, and that once America and Russia were both pitted against the Axis, their industrial might made the outcome only a matter of time – epitomised by the use of the atomic bomb in August 1945. In reality, the debate about the overall value of Bletchley Park has a troubling ‘What if?’ quality. Inevitably, we are encouraged to ponder the alternative universe of ‘no Ultra’. Ralph Bennett, like Harry Hinsley a Bletchley Park veteran turned historian, has expressed impatience with such counter-factual speculations, regarding them as a parlour game. He has argued that the absence of Ultra would have forced the faster development of other forms of intelligence, such as aerial reconnaissance.[40] Peter Calvocoressi, another distinguished historian who spent the war at Bletchley Park, has dismissed Hinsley’s assertions as ‘silly’.[41]

Some propositions can however be advanced with confidence. Ultra and other kinds of sigint contributed hugely to the outcome of the Battle of Britain. The breaking of naval Enigma changed the course of the Battle of the Atlantic, allowing the Admiralty to direct convoys away from concentrations of U-boats and bringing the level of ship losses down to a bearable, although still frightening, level. This in turn allowed a breathing space for more successful anti-submarine warfare techniques to be developed which would finally turn the tide in the battle against the U-boat in 1943. Ultra also contributed greatly to the British naval victories at the Battle of Cape Matapan (March 1941) and the Battle of North Cape (December 1943). Parallel code-breaking work by the Americans in the Pacific allowed the dramatic interception of the aircraft carrying the brilliant Admiral Yamamoto, architect of Pearl Harbor, which sounded the death knell for Japanese naval forces in the Pacific. It is impossible to understand the war at sea without comprehending the contribution of Ultra in the west and the breaking of a range of Japanese cypher systems in the east. Appropriately, it fell to a naval officer, Commander Edward Travis, to pilot Bletchley Park as it sailed forward into the post-war era.

Even in the spring of 1945, final victory in Europe had loomed like the end of an interminable school year – with the distant summer holidays already beckoning. Bletchley Park, with its nearby dormitories and improvised tennis courts, had looked rather like a vast boarding school waiting for the end of term. Post-war worries were not troubling many of the brilliant minds there. Instead, for the most part they were yearning for an end to war and a return to peacetime activities. The majority of Bletchley’s wartime residents were exhausted from years of gruelling hard work. The intellectual pressure had been enormous, and some had suffered nervous breakdowns: Jean Thompson, a Wren who worked at one of the outstations, recalls that they routinely referred to Bletchley Park as the ‘Nut House’.[42] Most code-breakers greeted the end of the war with relief, returning to their former activities in ivy-covered colleges, libraries and museums. However, a minority had been bitten by the intelligence bug. They understood the fundamental importance of what they had been doing for the future of international affairs, and would stay on.

Those who remained at Bletchley Park were also thinking of ‘escape’ – but in a different sense. For them, the end of the war did not so much offer an opportunity of personal freedom, but more the possibility of liberation for the GC&CS. Their remarkable achievements over the last five years suggested that GC&CS might cease to exist under the cloying direction of Britain’s traditional overseas secret service, SIS, where the senior staff were often failed cavalry officers recruited in White’s or Boodle’s. Instead, GC&CS might hope to become an intelligence agency in its own right, perhaps one of a new and different kind. Indeed, its rising status was already signalled by a gradual change in everyday usage from terms like ‘GC&CS’ and ‘BP’ to the rather grander cover name of ‘Government Communications Headquarters’, or ‘GCHQ’, which had been in intermittent use since early 1940.[43]

Bletchley Park had already taken some important strides towards becoming a fully-fledged intelligence service. Peter Calvocoressi, one of its distinguished wartime denizens, recalls that in its pre-war incarnation the Government Code and Cypher School was exactly what its name implied, ‘and no more’. It made up codes for use by the British government, and broke the codes of other nations. But at Bletchley Park, and especially under Gordon Welchman in Hut Six, code-breaking was gradually married to an intelligence process to provide a sophisticated system for sigint exploitation. No less importantly, Bletchley also designed a means for the secure and rapid distribution of sigint to essential customers, even in distant theatres such as South-East Asia. The sheer pressure of wartime exigency forced rapid and logical developments that might otherwise have taken decades.[44]

Another massive achievement was that Bletchley Park and its diplomatic equivalent at Berkeley Street in London were properly ‘integrated’, mixing up staff from the three armed services and civilians. This was immediately obvious to any visitor from the curious blend of uniform and civilian dress, often in exotic combinations. Occasionally a visiting Admiral or General would fulminate to see members of his service dressed in colourful pullovers, and demand that they return to full uniform. However, the top brass on day trips from Whitehall were little more than a temporary nuisance. During the 1940s a sigint service which mixed up civilians and personnel from the armed services was quite remarkable. It would take the Americans until the early 1950s to achieve an integrated organisation that mirrored Bletchley. In Nazi Germany as Calvocoressi recalls, the situation had been even worse, for there ‘six or seven different cryptographic establishments fought each other almost as venomously as they fought the enemy’.[45]

In the social anthropology of intelligence, sigint was emerging as the dominant tribe. ‘The Ultra community at BP saw itself as – perhaps was – an elite within an elite,’ recalled one code-breaker. Material gathered by other kinds of intelligence agencies was merely ‘Top Secret’, but sigint material was compartmentalised as ‘Top Secret-Ultra’. The ability to impose draconian security on its product would be a hallmark of a fully-fledged sigint organisation, and dominated its relations with its friends and allies in the code-breaking world. This security obsession also extended to people. The security rule at Bletchley Park was ‘Once in, never out.’ In other words, once people had worked in sigint, there was a reluctance to allow them to move to other areas of war work, and they were effectively ‘captive’ for the duration of the war.

Dominance was partly about size. By the end of the war, over ten thousand people were labouring under Bletchley’s direction. The expanded bombe effort alone led to the creation of five further outstations as far away as Stanmore and Eastcote on the outskirts of London. Working alongside GC&CS were the listening units of the armed forces, known as the Y services. Although these fed high-grade material to Bletchley Park, they also worked on low-grade material for their own purposes. Often considered ‘poor relations’, they derived their intelligence either from listening in to low-level tactical communications that were not encrypted, including clear voice traffic, or by simply analysing the flow of traffic. Analysing the patterns of radio traffic, including volume and direction, even without breaking the codes, could reveal a great deal of information about the enemy, and GC&CS worked closely with the armed services to develop what were known as the ‘Y stations’. Bill Millward, who continued to serve long after the war, recalls that Bletchley Park’s relationship to the Y services was to become ‘a sort of university of signals intelligence, developing techniques which all might share’.[46] The Y services had been largely responsible for deducing the enemy ‘order of battle’, the structure, strength and location of the units of the German armed forces. The Navy ran intercept sites at Scarborough and Winchester. The Army ran a site at Fort Bridgewoods near Chatham, and later opened a station at Beaumanor Hall near Loughborough in Leicestershire. The RAF were located at Cheadle in Cheshire, and developed a large new site at Chicksands near Baldock in Bedfordshire. Many of these locations would continue as sigint sites after August 1945.[47] All of them were symptomatic of an industrial revolution in secret intelligence: both Bletchley Park and the outstations operated like factories, with three gruelling shifts each day.

At a deeper level, there had also been a social revolution in British intelligence. Brilliant individuals who only a year before had been members of international chess teams or wrestling with obscure mathematical problems in Cambridge colleges, were now focused on intelligence. Remorselessly logical, they could see that Bletchley Park was the intelligence machine of the future. Moreover, they were outsiders, with no sense of bureaucratic anxiety and no fear of the ‘Establishment’. They fearlessly articulated what to them was self-evident. GC&CS, once a small school of code-breakers working in the service of SIS, had now vastly outgrown its parent organisation. Gladwyn Jebb, one of a number of rising British diplomats who were temporarily attached to intelligence duties during the war, noticed this dramatic change. The organisations like Bletchley Park had been forced to recruit widely from industry and the universities to fill their ranks, so they had forward-looking staff who brought with them modern organisational techniques.[48] Jebb complained that SIS had ‘too much of what I would call the “false beard” mentality … more especially amongst those who have been in the show for a very long time’. The world had moved on, he argued: ‘The idea of a deeply mysterious “Master Spy”, sitting in some unknown office and directing an army of anonymous agents, is as outdated as it is romantic.’[49]

The Americans had also opened the eyes of GC&CS to what was technologically possible. Although hobbled by the bitter Army–Navy divide, Washington nevertheless threw vast scientific resources at sigint. On their visits across the Atlantic, a core of determined individuals from Bletchley were able to glimpse what the future might hold. In 1944 a small group of talented British code-breakers began the long-range planning that would turn wartime Bletchley Park – with its chess players and crossword puzzlers – into Britain’s premier post-war secret service, with a strong sense of identity, a large budget and predatory designs on other agencies. Three key figures were instrumental in this: Gordon Welchman, the man behind Bletchley Park’s intelligence processing centre; Harry Hinsley, who would serve as the ‘sherpa’ for the Anglo–American–Commonwealth sigint summits after 1945; and Edward Crankshaw, who had handled wartime sigint discussions with the Soviets. Hugh Foss joined them on his return from a posting in Washington.[50]

On 15 September 1944, only weeks after the liberation of Paris, this planning group began to consider GC&CS’s post-war future. It was led by Gordon Welchman, who was Assistant Director for Mechanisation, and had also been responsible for Hut Six, where Enigma was broken. Some of the exciting ideas the group advanced for the future of GC&CS grew largely out of the Hut Six experience. It called for a more centralised ‘Foreign Intelligence Office’ as part of a coherent national intelligence organisation, and for a comprehensive body dealing with all forms of sigint, together with a modern signals security organisation with the latest communications engineering. This, the group believed, could become a truly modern ‘Intelligence Centre’ governing all types of interception activities.[51]

Welchman’s group was tough-minded. There were, it argued, few people in GC&CS with real ability in general planning and strategic coordination. They observed, ‘it would be difficult to count as many as a dozen’. This talent should not be wasted on the final year of the war against Japan. Instead, as soon as the war in Europe was over, ‘as many as possible of the few potential planners should be set to work in the direction of our three immediate objectives, instead of devoting more of their time to Japanese problems’. GC&CS should not lose touch with developments in the field of Japanese sigint problems, since there were interesting things to learn in this sphere. However, it should merely extract technical benefits from the Japanese War, rather than expend resources upon it. British commanders in Burma, like Field Marshal Bill Slim, realised that they were now a low priority for the intelligence services, and complained bitterly about it.[52]

GC&CS realised that speed was of the essence. It was ‘imperative to make an approach to the present Prime Minister at the earliest possible moment’. Any successor to Churchill, it reasoned, however sympathetic, could not have a real appreciation of ‘the fruits of intelligence in this war’, or Churchill’s keen appreciation of the importance of tight security. In Churchill it had a heavyweight advocate, and it feared a return to the pre-war situation of under-recognition of what sigint could achieve; even now, the true scale of its wartime output was known to only a very few in high places. Moreover, the really talented sigint planners were newcomers, and would soon be recalled to their pre-war occupations unless some positive action was taken to retain them. Quite simply, this came down to cash. GC&CS had to have the status to secure ‘a sufficiently liberal supply of money to enable it to attract men of first rate ability’, particularly engineers and electronics experts. It was also aware that it would have to give equal weight to all types of intelligence about foreign countries, ‘including scientific, commercial and economic matters’. This was a tacit reference to the targeting of friendly states.[53]

In January 1945, the torch of post-war planning passed to William F. Clarke. Clarke, who had served continuously in code-breaking from 1916, warned that the ‘enormous power wielded by the Treasury’ might soon be brought to bear on GC&CS. As had happened in 1919, work on military cyphers might cease in favour of concentration on diplomatic material only. This, he insisted, could be ‘disastrous’, because the resulting damage to ongoing cryptographic research might mean that in the event of a sudden future conflict, enemy military traffic would prove inaccessible. Even more problematic was the challenge of building up the prestige of GC&CS. Its very secrecy was its worst enemy, ensuring that many in elevated government circles did not know its true value. There was also the ‘potential danger’ of a Labour government coming to power, since the interwar Labour government had found many aspects of the secret state to be repellent.

Clarke also paused to consider the emerging United Nations. Allowing himself some momentary Utopian thoughts, he observed that if the new organisation took the step of abolishing all code and cypher communications, this action ‘would contribute more to a permanent peace than any other’. However, he conceded that this ‘is probably the counsel of perfection’, and was highly improbable. Instead, he predicted that energetic code-making and code-breaking would persist into the post-war world. On the matter of who would control the British code-breakers, he felt that in the past neither the Admiralty nor the Foreign Office had been satisfactory. The current system of control by SIS also brought with it ‘certain disadvantages’. Clarke vigorously asserted that GC&CS should break free, not only of SIS but also of the Foreign Office. Instead it should be a separate organisation under either the Chiefs of Staff or the Cabinet Office, and should be regarded as a wholly separate third secret service.[54]

As late as October 1944, some senior figures at Bletchley were still arguing for reabsorption by SIS. John Tiltman, the Soviet specialist, argued that the code-breakers should be ‘closely fused with S.I.S. under the Director General [Sir Stewart Menzies] as the one and only Intelligence producing service’.[55] However, the stock of Menzies was continuing to fall among senior figures in Whitehall. In January 1945, the Chairman of the JIC, Victor Cavendish Bentinck, concocted his own influential vision of ‘the intelligence machine’. He suggested that GC&CS should remain under the overall direction of ‘C’, but at the same time it would be a separate organisation and ‘not a part of SIS’. It would boast its own budget alongside the other secret services as part of the Secret Vote, Britain’s quaintly titled intelligence budget.[56] It was thus Commander Edward Travis, not Menzies, who determined the final shape of GC&CS shortly after VJ-Day. Although peace had arrived, Travis’s mind was already focused on possible future conflict with the Soviets. Recalling the earliest days of the last war, he observed, ‘When information was most urgently required, very little was forthcoming.’ The next war was likely to be of shorter duration, with little time for mobilisation. In such a conflict the British would have to fight with what they had. It was essential that continuity be maintained, and that rapid expansion was possible on the eve of war.

Exactly when the post-war term ‘GCHQ’ came into common usage is a matter of dispute. It was first used as a cover name to confuse workmen dropping off furniture at the Bletchley Park site as early as the end of 1939.[57] By 1946, although technically still merely a cover name, it was used more and more widely to denote Britain’s code-breakers. Travis decided that the new post-war GCHQ would be divided into five groups run by his key subordinates.[58] To cover its multifarious tasks, he hoped to have a thousand civilians plus a hundred military staff at a new sigint centre located somewhere near to the policy-makers in London. By contrast, the outlying Y stations would be manned by about five thousand additional personnel, of whom only a few would be civilians. GCHQ’s own core staff fell rapidly from an end-of-war strength of 8,902 to a projected 1,010 for 1946.[59] Despite the dramatic drop in numbers, Travis concluded that the post-war deal he had struck with the Treasury was ‘on the whole most satisfactory’. For him it was about quality rather than quantity. A few days before Christmas 1945 he explained: ‘The war proved beyond doubt that the more difficult aspects of our work call for staff of the highest calibre, the successes by the Professors and Dons among our temporary staff, especially perhaps the high grade mathematicians, put that beyond doubt.’ He wanted suitable conditions with which to attract these sorts of people, although he knew this would be difficult.[60] Captain Edmund Wilson, Travis’s Principal Establishment Officer, echoed this view, arguing that of the 260 officers to be kept on in their post-war establishment, some two hundred of them must have not only initiative but also ‘first class brains’.[61]

Where would GCHQ’s new centre be? What it craved was a site in central London, next to the policy-makers, but even with the post-war demobilisation of many government departments, nothing suitable could be found. The solution was what John Betjeman would immortalise as ‘Metroland’. GCHQ moved to the outer fringes of north-west London, close to Harrow and Pinner. The precise location was Eastcote, which had been used as a wartime outstation of Bletchley Park. It was also close to Dollis Hill, where the laboratories of the Post Office Research Department had built the remarkable ‘Colossus’ computer. Together with Stanmore, Eastcote was one of two large outstations built in 1943 to accommodate the ever-expanding number of bombes that were being used to cope with the flood of Enigma traffic. However, while it provided reasonable single-storey buildings that were superior to the huts of Bletchley, the overall site was regarded as cramped and unattractive. In June 1946, William Bodsworth, a British code-breaker, returned from a period in America to the cold and rain of an English summer to take over GCHQ’s Soviet section. He found his first sight of Eastcote ‘frankly shattering’. Expecting ‘a nice old country house’, instead he found it to be ‘more cheerless than any of the temporary buildings I have seen in this racket either here or abroad’.[62]

Those who were leaving Bletchley for good and returning to civilian occupations were given the security warning of their lives. Edward Travis issued a ‘Special Order’ to everyone in GCHQ. He began by thanking them all for their admirable achievements and the substantial contribution they had made to the winning of the war. He then moved quickly on to the matter of maintaining secrecy, even after the end of hostilities. ‘At some future time we may be called upon again to use the same methods. It is therefore as vital as ever not to relax from the high standards of security that we have hitherto maintained. The temptation to “own up” to our friends and families as to what our war work has been is a very real and natural one. It must be resisted absolutely.’[63] However, in the Far East, the secret of ‘Magic’, the breaking of Japanese diplomatic codes, was already out. When Bruce Keith, commander of the vast British sigint station located at HMS Anderson in Ceylon, tried to outline Travis’s tight security measures, some of his subordinates openly laughed at him and observed that ‘the Americans had spilled the beans in the paper the other day’.[64]

The move from Bletchley to Eastcote was undertaken during early 1946 in four main parties. The first was the priority group, and included the Soviet and East European Division; the last arrived in April 1946.[65] Staff turning up in leafy Pinner in search of lodgings were allowed to refer to their place of work as ‘GCHQ’, but they were told firmly that any reference to ‘signals intelligence’ was forbidden.[66] Between 1945 and 1948 the term ‘GCHQ’ was used interchangeably with both ‘London Signals Intelligence Centre’ and ‘Station X’.[67]