Successive prime ministers needed to know the Soviet Union’s capabilities and intentions, including its nuclear arsenals and technological developments – and, crucially, whether it would use them. A great deal was at stake. Intelligence also had a more active, and potentially explosive, role to play. It became crucial in fighting a large-scale underground struggle. With open warfare now too dangerous to contemplate, conflict was forced into a lower key. Subversion, espionage, insurgency and propaganda became the weapons of choice. Clement Attlee was the first prime minister to be forced to adjust to this ‘hot peace’, and to recognise its implications for the active use of intelligence in peacetime. He was well aware of the difficulties. Spoilt by the Ultra material during the war, the new government had to adapt to a lack of high-grade intelligence, since it was not reading many Soviet communications. GCHQ, as GC&CS had become in 1946, could not provide direct insights into the mind of the enemy. Attlee himself privately acknowledged that ‘The difficulties in dealing with Communist activities are far greater than anything which we have had to face before, for the iron curtain is very hard to penetrate.’2
Attlee’s premiership was sandwiched between two governments led by Winston Churchill, an enthusiastic – even flamboyant – advocate of secret service. By contrast, Attlee is remembered neither as a natural Cold Warrior nor as an avid consumer of intelligence. He was a modest and sensible man; the last ever prime minister to be challenged to a duel – which he declined, telling the accuser not to be so silly.3 Yet, unlike prime ministers who had served during the interwar period, Attlee and his colleagues did not arrive in office ignorant of the workings of the secret world. As an integral part of the wartime coalition he had been aware of MI5 and MI6 long before being elected prime minister.4 As Winston Churchill’s deputy prime minister, he had been discussing reform of the secret services as early as 1940, and also experienced the vital contribution made by ‘most secret sources’, especially signals intelligence, first hand.5 During the war, Stewart Menzies had picked out Bletchley Park decrypts not only for Churchill, but also for Attlee.6
Churchill had asked his deputy to preside personally over some of the most sensitive wartime issues. In December 1943, Attlee had chaired a staff conference that looked at the ‘highly disturbing’ issue of German penetration of SOE in Holland.7 And he was not alone. His own deputy prime minister, Herbert Morrison, had been wartime home secretary, while his chancellor of the exchequer, Hugh Dalton, had run SOE. Attlee was therefore quite right to assert that he ‘had had full experience of high and responsible office’, and ‘understood the machinery of government’.8 As a consummate committee man, machinery was his strength. Churchill may have boosted Britain’s intelligence community, but it was Attlee who refined the secret structures that ensured its smooth running over the next half-century.
Clement Attlee had endeared himself to Churchill personally as Labour’s most vocal enemy of appeasement in the late 1930s. Indeed, it was his refusal to join a coalition government led by Chamberlain that had ushered in Churchill as premier in May 1940. Thereafter, Attlee, together with Anthony Eden and Harold Macmillan, completed the Churchillian intelligence revolution. Schooled in the importance of secret service during the long years of conflict with Nazi Germany, the need to integrate intelligence into the core business of government was second nature to them. The amazing achievements of MI5, MI6, SOE and especially Bletchley Park resonated with Britain’s rulers over the next two decades, a period during which 10 Downing Street was consistently run by ministerial figures from Churchill’s wartime coalition. Already well-versed in the clandestine workings of intelligence, as prime minister Attlee oversaw the growth of an intricate secret state prosecuting the Cold War both domestically and overseas.9 As Britain faced severe economic decline, intelligence was an area in which it could perhaps still lead the world, while secret service provided opportunities for fancy footwork that dodged imperial retreat.10
The new prime minister was no stranger to domestic counter-subversion. Churchill had inducted Attlee into this sensitive area almost as soon as he joined the coalition government in May 1940.11 Owing to his intense fear of fifth columnists, Churchill had wished to progress with the internment of enemy aliens, and he instructed Attlee to liaise with MI5 on the matter. Attlee agreed with its senior counter-espionage officer, Guy Liddell, that ‘the liberty of the subject, freedom of speech etc were all very well in peace-time but were no use in fighting the Nazis’.12
As prime minister, Attlee continued to value MI5, not least to ‘detect attempts to penetrate our defence organisation’. He also believed that MI5 should be free from political control, separate from government and police machinery.13 Yet upon his election in July 1945, he was cautious in his dealings with Britain’s security agencies. They were not natural bedfellows.14 Aside from Philby, Burgess and Maclean, senior British intelligence officers were hardly renowned for their love of socialism. According to one barbed remark in Liddell’s diary, the state socialism pursued by Attlee’s government ‘differed little if at all from Communism by evolutionary means’.15 Conversely, the Labour Party’s opinions of MI5 were framed by historic antagonism dating back to the Zinoviev affair. More recently, memories of internment, censorship and other infringements of civil liberties perturbed the new Members of Parliament who filled the government benches following Labour’s landslide victory – a victory which took MI5 by surprise.
Attlee was being watched carefully by both left and right. During an election broadcast in July 1945, Churchill had rather cruelly suggested that if Labour was elected, his former wartime colleagues would create ‘some form of Gestapo’.16 Where would ordinary people be, he asked, ‘once this mighty organism had got them in their grip?’17 Attlee feared accusations from the Labour left that he was mounting a witch-hunt if he took obvious measures to keep British communists away from sensitive material.18 His understandable caution over domestic security during the early years of his premiership frustrated senior figures in MI5. Within just months of the election, they began moaning about government prevarication.19
Towards the end of his first year in office, Attlee expressed strong concerns about MI5’s files on individuals, and demanded that they be kept clean of anything that did not come under the service’s terms of ‘defence of the realm’. In his usual brusque manner, he made it abundantly clear to all concerned that MI5 was not to have the names of anybody on its index cards who was not considered a threat to national security. The issue played heavily on Attlee’s mind over the early summer of 1946. After some weeks he summoned MI5’s director-general to his office to check if the records had indeed been cleared of irrelevant material. Despite the fullest assurances, Attlee remained concerned. Churchill’s pointed comment had clearly stung, and the prime minister ‘was still afraid that the Opposition might accuse him of running a Gestapo’.20
Everyone expected the talented Guy Liddell to be next in line for the top job at MI5. When David Petrie retired as director-general in spring 1946, however, Attlee controversially appointed an external candidate. After an impressive career in the police, Percy Sillitoe had hoped for a gentle retirement running a sweetshop in Eastbourne. He clearly did not expect to be catapulted into the murky world of international espionage, but Eastbourne’s loss was Britain’s gain. Sillitoe accepted the position, and the relationship between Downing Street and MI5 swiftly improved.21
Attlee