GCHQ. Richard Aldrich
the autumn of 1943 the security situation looked much worse. The Italians had now capitulated, and captured Italian code-breakers revealed their successes against British codes. Captain Edmund Wilson, who helped to look after cypher security at Bletchley Park, held prolonged ‘conversations’ with Commander Cianchi, head of the Italian Cryptographic Bureau in Rome, and his staff during late 1943. Wilson explained that he could hardly call them ‘interrogations’, since Cianchi had given all of Italy’s secret information so happily and freely. Wilson said that ‘very valuable information’ on the breaking of British naval cyphers had been obtained, and that Britain was ‘extremely fortunate’ to have the cooperation of its former opponents. He pressed his colleagues to be ‘very careful indeed in the use they made of the information’ from these sources.[25]
The TICOM raids into Germany later confirmed that British naval cypher security had been especially weak. B-Dienst, the German naval sigint service, had been reading British naval codes and cyphers easily at the start of the war. In early 1940 this had allowed it to read British plans for the Narvik raid in Norway, contributing to Germany’s success in repulsing that action. In 1942, the Dieppe raid had also been given away to the enemy before it took place due to poor cypher security. Incredibly, the Germans had been given a full five days to prepare for this ‘surprise attack’. Allied troops – mostly Canadians – paid for this dearly in the slaughter that followed. B-Dienst achieved the height of its success against Atlantic convoy traffic in 1943, allowing alterations of convoy routes to be radioed to U-boat commanders within a few hours.[26]
The autumn of 1943 saw a long-overdue inquiry into the security of British cyphers, carried out by Brigadier Chitty, who began by visiting Bletchley Park. His findings did not make for comfortable reading. ‘It is true,’ he reported, ‘that of the fourteen sections working at B.P. [Bletchley Park] one is named Security of Allied Communications. From a total staff of some six thousand, however, the part-time services of only one man (Dudley-Smith) plus two or three girls, are spared to equip this section.’ At a higher level there was a supervising body called the Cypher Security Committee, supposedly chaired by Sir Stewart Menzies, but this had not attracted Menzies’ interest. Moreover, it lacked the power to compel Whitehall departments to change any practices that they thought lax. Chitty had done a spot check of twelve departments around Whitehall, and found that few were taking cypher security seriously. Britain needed a decent operational security section at Bletchley Park, and a proper supervisory board with teeth.[27]
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