Several additional factors cast shadows over the proposed special relationship between Britain and the United States. The British harboured a justified fear of the cavalier, indiscreet way in which the Americans treated the fragile nature of cryptographic security. For example, at the height of the Great Depression and in desperate need of money, Herbert Yardley, the former head of the American cryptographic bureau who had worked with the British and the French during the last years of the First World War and into the interwar period, published The American Black Chamber.51 The book was based on his personal experiences and exposed the work not only of the U.S. bureau but also of his allies, particularly the reading of Japanese envoy messages during the Washington Naval Conference in 1920–21. As expected, the book was an instant bestseller on three continents. It succeeded in pulling the bon vivant and rumoured serial womanizer out of his financial bind but left him a pariah. Immediately, it set off a firestorm of controversy and bitterness, with the British in particular feeling betrayed.
In British eyes, Yardley exemplified a careless American brashness that should be avoided at all costs in an industry where discretion and security were paramount. Eventually, he resurrected his career, offering his talents in mercenary fashion first to Chiang Kai-shek’s Nationalist party in China in the late thirties and then to the Canadian government, which in 1940 seemed bent on joining the exclusive signals intelligence club. His tenure was short-lived: once the British got wind of his employment, the Government Code and Cypher School refused to continue its support for the novice Canadian signals intelligence community as long as Yardley remained on staff. And so he was fired—the day before the Japanese attack on Pearl Harbor—and replaced by Oliver Strachey, a legendary Bletchley Park cryptanalyst, whose work on breaking German agent traffic led to the ISOS process being named after him: Intelligence Service Oliver Strachey.
This British fear was entirely genuine and legitimate. The Americans had not experienced the same level of cryptographic success that the British had already enjoyed for decades—first during the Blinker Hall days in the Great War and later in the early years of the new war. As such, cryptography, at least at first, did not maintain the same pedestal position as it did with the British, who viewed the Americans as essentially loose cannons when it came to security. The British knew that American codes and ciphers were notoriously porous and that even the State Department cipher had been penetrated by friend and foe alike. In England, Bletchley Park and cryptographic work in general came under the control of the Foreign Office and the Secret Intelligence Service, while in the United States the navy, the army, the FBI and the State Department all delved into signals intelligence and cryptography independently for their own, at times competing, purposes. Protecting their fiefdoms became their main focus, and the lack of a central coordinating body left the British fearful that one jealous, ignorant or otherwise malicious dispute could jeopardize their whole mission.
Despite this mistrust, when events in the Atlantic seriously heated up, the British were forced to approach the Americans about becoming active participants and intelligence partners in the war at sea—even if, ideally, they would keep them as limited intelligence partners. That meant that the issues surrounding Germany’s Enigma machine became the major points for discussion in most of their intelligence dealings.
Neither side at first rushed into the other’s arms, but despite British promises of full disclosure, it was the Americans who extended the first hand in late 1940, when they gave Bletchley Park a reproduction of the “Purple” machine that the Japanese used to encipher diplomatic messages. That allowed Britain’s Far East Combined Bureau in Singapore to attack Japanese ciphers.52 Following on the heels of this historic exchange, Churchill permitted representatives from the Government Code and Cypher School to discuss Bletchley’s breakthroughs into all forms of the Enigma, but then, despite earlier promises, he pulled up short of authorizing a full exchange of technologies. Although the Americans demanded a physical specimen of a captured Enigma for their cryptanalysts to work with, the mission team they sent to Bletchley Park for two months late in 1940 came away with only a paper copy of the inner workings of the machine. Citing security concerns and a potential redundancy of work, the British guarded their precious commodity tightly. In addition, the Americans were not permitted to take notes about anything related to the Enigma, nor could they view documents or other material about its solution.53
The sudden change in the British approach to sharing intelligence with the Americans was a curious development that warrants clarification. On February 13, 1996, a little over two years before he passed away, I met with the recently knighted Sir Harry Hinsley, who, fresh from his valuable analytical work in Hut 8 in the early years of the war, had gone on to be the GC&CS representative for naval cryptographic negotiations with the Americans for the remainder of the war and for some time after. He then returned to St. John’s College, Cambridge, where he enjoyed a stellar academic career as an international relations historian and, in particular, as the author of the voluminous official history of British intelligence in the Second World War.
And so it happened that, five decades later, when I arrived in Cambridge after an overnight flight from Montreal for our scheduled meeting, I was told at the college that both Sir Harry and Lady Hinsley were at home ill, but that I should phone him at once. In his legendary enthusiastic way, Hinsley refused my offer to come back on another day. “My dear boy,” he said, “you have come a long way across the ocean to see me—and you shall.” For Sir Harry, “all the way across the ocean” conjured up a two-week journey on an ocean liner that had to ply U-boat-infested waters. He insisted that I come to his flat near the university. By this time in his late seventies and rather gnomish in stature, he greeted me with a wide smile and an outstretched hand, withered and malformed by rheumatoid arthritis. For the next few hours we sat and discussed signals intelligence, Ultra and intelligence-sharing with the Americans. On that point he confided, “control of the technological know-how was the overriding theory in guiding GC&CS relations with the U.S.”54
Harry Hinsley made it clear to me that, from the start, the British were adamant about agreeing to a partnership only after “it became obvious that another power was on its way to create the technology necessary to discontinue reliance on GC&CS.”55 If confronted with this scenario, they would “provide … any information they required from this type of technology, partially to protect the source, but primarily to protect their monopoly.”56 In other words, it was one thing to open the taps to the pipeline and allow the Americans as much of the product as they required, but under no circumstances should they help the Americans find and develop their own deposits, let alone gain the knowledge to create their own refinery and pipeline system. They were adamant that control must remain in British hands, and only if met with an inevitable takeover or duplication would they move quickly to establish a full working partnership.
When the British achieved the first breaks into the three-rotor naval Enigma in early 1941, they were more than happy to offer the products of their findings to OP-20-G, the acronym used to denote the “Office of Chief of Naval Operations (OPNAV), 20th Division of the Office of Naval Communications, G Section / Communications Security”—the Washington-based version of the Operational Intelligence Centre. The British needed material co-operation from the U.S. Navy to protect their shipping in American waters, and the provision of Special Intelligence seemed a small price to pay for American assistance during this period of neutrality.
By June, a regular delivery of Special Intelligence passed from England to the United States, either through an Ultra Secret radio relay link known as Hydra (at a specially built facility known as Camp X located just outside Toronto on the shores of Lake Ontario) or via cable and diplomatic pouch direct to the offices of the British Security Coordination in the Rockefeller Center in New York.57 In August, the Government Code and Cypher School posted a liaison officer to OP-20-G to handle Special I
ntelligence. By the time Pearl Harbor was bombed on December 7, the United States and Great Britain had been limited partners for almost a year.
But the relationship was tense that December and, according to Godfrey, quickly developed into a “very prickly subject.”58 Less than a week before Pearl Harbor, complaints from the United States Navy put a strain on the special relationship. Having waited for more than a year for a reciprocal delivery of the naval Enigma machine they had requested earlier, the U.S. Navy now accused the British of holding back on Enigma-related material. It threatened to withhold further information on the Pacific unless it received full reciprocal information on European work. In response, the GC&CS representative in Washington warned: “There is a grave unrest and dissatisfaction in free exchange of Special Intelligence … You will appreciate the importance of this matter as United States are developing rapidly. The question should be faced and settled with the least delay or our relations will deteriorate and lost ground will be hard to recover.”59
Up to this point, the Operational Intelligence Centre had been providing the Americans with daily reports listing U-boat dispositions as known through Special Intelligence. However, when the wolf packs shifted to American shores and, soon after, the four-rotor Enigma appeared, that service was quickly snuffed out; an already tense relationship was left near the breaking point.60
Faced with legitimate demands from the Americans for help in curbing the German U-boat feeding frenzy off the American coast inflamed by the blackout, the British found themselves in an awkward situation. At first, not realizing that the Americans were planning to embark on their own design for a Bombe, they explained that they had neither the time nor the machines to solve the issue—an honest response but, nonetheless, a grave miscalculation. The Americans, who had been content at first to take a back seat and play a supporting role in the signals intelligence effort in the Atlantic, were no longer prepared to sit idly by, given their own skyrocketing shipping losses and the failure of the British to produce the cryptographic goods promised. The United States had genuine operational concerns. By June 1942 the head of the U.S. Army, General George C. Marshall, told Admiral Ernest King, the head of the United States Navy, that “losses by submarines off our Atlantic seaboard and in the Caribbean now threaten our entire war effort … I am fearful that another month or two of this will so cripple our means of transport that we will be unable to bring sufficient men and planes to bear against the enemy.”61
If the losses continued, operational issues would turn into political issues as well. Soon enough the press would begin to ask even more difficult questions about the mounting number of sinkings and the loss of life, and the lack of offensive action would lead to public demands for answers. The congressional or Senate investigation that would inevitably follow would force President Roosevelt to pressure the Navy to adopt corrective measures. And those measures in turn could well mean that the Americans, with their deep coffers, would press ahead on the naval Enigma issue, leaving the British behind if necessary.
In the early spring of 1942, the British learned that the Americans were indeed taking the first of several huge steps in that direction. Tucked away in an obscure structure innocuously named Building 26 on the grounds of the National Cash Register Company in Dayton, Ohio, the Americans had assembled an impressive array of intellectual talent and embarked on their own Bombe-building scheme, which was given equal priority and funding with the Manhattan Project—the attempt to build the world’s first atomic bomb.62 How long it would take to achieve results was anyone’s guess, but it was clear that the Americans were embarking on a parallel approach to the problem. This overt industrialization of the American cryptographic mission, backed by millions of dollars (trillions by today’s standards), meant that the clock was indeed ticking on British efforts at Bletchley Park.
In response, the Government Code and Cypher School sent a team of cryptographic liaison officers across the Atlantic to exercise damage control. It was led by Lieutenant Colonel John Tiltman, or “the Brig” as he was later affectionately known in intelligence circles (he became a brigadier in 1944), one of Bletchley Park’s finest cryptanalysts on non-machine systems. Tiltman had been an early and eager advocate for British co-operation with the Americans in cryptology, and his task now was to buy time for the British to solve the four-rotor riddle by direct or indirect methods. His précis on Enigma policy, written in 1942, confirms what Hinsley referred to during my interview with him. Operating under clear instructions from both Stewart Menzies, the head of the Secret Intelligence Service, and the “gruff, rough and burly” Edward Travis, the loved and respected successor to Alastair Denniston at GC&CS, Tiltman was asked to “point out that we did not wish to hide from the services in Washington the details of our successes, but that we wished to discourage them from attempting any exploitation until it became essential.”63 Failing that, he was to channel or quarantine American angst and determination so as to minimize any damage to Britain’s own programme either through competition or security leaks.
When Tiltman arrived in the United States, tension was running high, and tempers among American cryptanalysts were shattered and thin. Greeted at his first meeting with open derision by some American cryptanalysts, the thoroughly professional Tiltman kept his equilibrium, recording only that it was “clear that the [U.S.] Navy Department were extremely disturbed over the German U-Boats situation.”64
Despite the rough beginning, the British mission produced encouraging results. First, Tiltman smoothed ruffled feathers by candidly revealing the problems Bletchley Park faced with the Germans’ recent introduction of a four-rotor machine—a move that apparently thawed the tense atmosphere after the Americans, who had received no previous confirmation of the existence of this new machine, realized that the value of their initial work on the three-rotor Enigma was now moot.65 Despite the current critical situation, he downplayed the need for the United States to develop its own Bombe, assuring the Americans that the British had one in the works that would crack the machine in the near future. Finally, he promised to open up the stingy lines of communication and share more information on naval Enigma. He even invited the U.S. Navy to send a team of experts to Bletchley Park to see everything they were doing to solve the crisis.66 The Americans now realized that “thefts, German errors, and cryptanalytic craftsmanship had been, and would be, the only ways into naval Enigma.”67
Before long, Tiltman won the Americans over, essentially through his honesty and in part thanks to his disarming nature, which they viewed as the embodiment of British eccentric brilliance and quite unlike the intellectual and cultural condescension they had expected. They warmed to his relaxed style, devoid of deference for uniform or tradition, along with his paternalistic but never patronizing use of “old boy” with everyone he encountered.
Reporting back to Commander Travis, Tiltman explained that he had reached agreement with the United States Navy that the solution and exploitation of Enigma could best be carried out by Bletchley Park.68 He warned, however, that certain considerations must be taken into account. “In view of the fact that they [the Americans] are now at War and have a vital interest in Submarine traffic,” he wrote, “they are entitled to results or a detailed statement as to why this traffic cannot be read at present and what are the prospects for the future.” The fact that this compromise was only a band-aid solution was not lost on Tiltman. He warned Travis that “unless a rapid and satisfactory solution is found[,] the High Command will insist on their naval Cryptanalysts attempting to duplicate our work on E.”69
It was clear that Tiltman’s visit had achieved the desired effect of calming the Americans, at least in the short term, but it was equally certain that the clock was ticking. At some point, likely in the near future, the U.S. Navy was bound to become an undeniable force with an insatiable appetite in the world of British-dominated cryptography. In realpolitik terms, this realization meant that the British could either attempt to solve the issue immediately
or, in the face of futility, admit as much to the American Navy and bring them on board as full rather than limited partners. Full co-operation with the Americans on the four-rotor Bombe could be viewed as an “acceptable” loss—in fact, as the cost of retaining the rest of their slowly collapsing cryptographic monopoly.
With all these complexities in mind, the best course of action for the British was to hedge their bets by acting on both fronts simultaneously: they would move ahead full throttle on their own development but, when necessary, co-operate with the United States. Either way, even if both sides could develop an operational four-rotor Bombe in 1942, they would still require pinched material for it to work efficiently. Another successful pinch was therefore of the utmost urgency.
SEVEN
KICK AT THE DARKNESS
We must not lose our faculty to dare, particularly in dark days.
—WINSTON CHURCHILL, MARCH 24, 1942
One Day in August Page 17