"That's all right, Peter, old chap, I don't need to know about Ohm's law. I read Greats."
"Good God," I exploded, "every schoolboy learns about Ohm's law!"
The head of D Branch, Graham Mitchell, was a clever man, but he was weak. His policy was to cravenly copy the wartime Double Cross techniques, recruiting as many double agents as possible, and operating extensive networks of agents in the large Russian, Polish, and Czechoslovakian emigre communities. Every time MI5 were notified of or discovered a Russian approach to a student, businessman, or scientist, the recipient was encouraged to accept the approach, so that MI5 could monitor the case. He was convinced that eventually one of these double agents would be accepted by the Russians and taken into the heart of the illegal network.
The double-agent cases were a time-consuming charade. A favorite KGB trick was to give the double agent a parcel of money or hollow object (which at that stage we could inspect), and ask him to place it in a dead letter drop. D Branch was consumed every time this happened. Teams of Watchers were sent to stake out the drop for days on end, believing that the illegal would himself come to clear it. Often no one came to collect the packages at all or, if it was money, the KGB officer who originally handed it to the double agent would himself clear the drop. When I raised doubts about the double-agent policy, I was told solemnly that these were KGB training procedures, used to check if the agent was trustworthy. Patience would yield results.
The truth was that the Russians used double-agent cases to play with MI5, identify our case officers, disperse our effort, and decoy us from their real operations. The standard of MI5 tradecraft was appalling. KGB monitoring of our Watcher radios certainly gave away our presence on a large number of the double-agent cases. But the D Branch case officers were just as bad, rarely employing anything other than the most rudimentary countersurveillance before meeting their agents. An entire department in the Foreign Office provided MI5 with "chicken feed," secret material given to double agents to pass on to the Russians as proof of their bona fides. The chicken feed consisted of wholly unbelievable faked secret documents about weapons we did not have, and policies we had no intention of pursuing. I raised the whole question of the chicken feed with D Branch, and pointed out that the material was bound to be spotted as suspect, and that only real secrets would convince the Russians. That, I was told, was quite out of the question.
The other main area of D Branch activity was in the Emigre communities. The agent running sections of D Branch ran extensive networks, and used agents in London to recruit others inside their host countries. This was a particularly attractive option for MI5. Emigres were easy to recruit, and enabled MI5 to compete directly with MI6 in the production of Iron Curtain intelligence, much to their irritation. But in reality, by the early 1950s, these emigre rings were utterly penetrated by the KGB, or their allied Eastern European services, and as with the double-agent cases, served only to soak up our effort, and identify our agent runners.
MI5 were living in the past, copying the techniques of Double Cross, in an intelligence world which had changed enormously since the war. They lacked not only case officers with the requisite skills but, much more important, the codebreaking advantages MI5 had enjoyed over the Germans.
Throughout the 1950s, MI5 avoided confronting the most obvious counterespionage problem facing Britain at that time - the results of the 1930s Soviet infiltrations of the British Establishment. The extent of the recruitment of "Stalin's Englishmen" became apparent with the convictions of Alan Nunn May and Klaus Fuchs for nuclear espionage in the late 1940s, closely followed by the defection of Burgess and Maclean in 1951. It was obvious to anyone with access to the papers that the Russian Intelligence Services had capitalized on the widespread intellectual disillusionment among well-born British intellectuals of the 1930s, and succeeded in recruiting important agents, some of whom, at least, remained loyal to the Soviet cause after the war.
The defections of Burgess and Maclean traumatized MI5. Philby and Blunt also fell under suspicion, but faced with their adamant denials, the cases ran quickly into sand. The only remaining way forward was to launch a major, intensive program of research and investigation among the network of people who had been friendly with the two diplomats at Oxford and Cambridge. Such a policy entailed enormous difficulties. Most of those friendly with Burgess and Maclean were now rising to positions of considerable eminence, not just in the Intelligence Services but in the Civil Service as well. There was potential political embarrassment if such inquiries leaked at a time when all concerned were doing everything to suppress any information about the defections. Moreover, there was always the ghastly possibility that vigorous investigations might provoke further departures to Moscow, with incalculable consequences. No one was prepared to grasp the nettle and from 1954 onward all work virtually ceased, MI5 apparently believing that the new vetting procedures then being implemented were enough to protect the national security. It was like locking the chicken house door with the fox inside.
One man stood out against this policy of neglect. He was Arthur Martin, a former Army signals officer who joined MI5 soon after the war. Martin quickly proved himself a brilliant and intuitive case officer, handling in quick succession the Fuchs and Maclean investigations, ably assisted by Evelyn McBarnet, a young woman research officer, whose contribution to these cases has never been adequately acknowledged. Martin had one huge advantage in his approach to counterespionage work: he never attended a public school. Once it was known that a serious leakage of secrets had occurred at the British Embassy in Washington, the conventional view was to search for the culprit among the clerks, cleaners, and secretaries. But Martin realized at an early stage that the culprit was a senior diplomat. He doggedly pursued the investigation, and was only foiled when Maclean defected.
After the defections, Martin pressed the management of MI5 to sanction urgent inquiries into the whole complex network of Communist infiltrations of Cambridge in the 1930s. But his requests for permission to interview the numerous members of the Philby, Burgess, and Maclean social circles were mostly refused. For two years he struggled against this woeful policy, until finally he went to see the Director-General, Dick White, and told him that he intended to resign and take a job with the new Australian Security Intelligence Organization, ASIO.
White, who had a high regard for Martin's abilities, persuaded him to go to Malaya instead, as MI5's Security Liaison Officer, until the climate in D Branch was better. It was, at the time, a vital job, and Martin played a leading role in the successful counterinsurgency campaign in Malaya, but the consequences for counterespionage were disastrous. For most of the decade MI5's most talented, if temperamental, officer was missing.