Joseph E. Persico (18 page)

FDR retained his penchant for the melodramatic, for spies over electronic espionage. At roughly the same time that Rowlett and his crew were breaking Purple, Captain James Roosevelt, the President's eldest son, who had entered the Marine Corps in 1940, was called to the White House. As he later described the occasion, “[F]ather summoned me for a secret mission.” Jimmy was to accompany an Army major, Gerald Thomas, on a trip through the Philippines, China, Burma, India, Iraq, Egypt, Crete, Palestine, and Africa. As far as Major Thomas knew, their mission was to report any military buildup and gauge the adequacy of U.S. supply lines to these places. But FDR had another assignment for Jimmy. Behind closed doors in his private study he told his son, “This must be completely confidential. The Congress, the press and the public would never approve my message, but I consider it critical to the morale of countries we must support.” Jimmy was to give ceremonial gifts to the leaders of the nations he visited, then take these people aside and deliver a confidential message from the President. They were to be told that while the United States was still officially neutral, Roosevelt “would do everything he could to help those who were at war” fighting the fascists. Jimmy was also to convey a pledge that would certainly have rattled isolationist Americans. He was to confide to his hosts FDR's belief “that we might well be at war before long and that we then would pitch in with both hands to help them.” In effect, Jimmy was to tell these leaders, “Hang on until we get in.”

The President had a final warning before his son's departure: “If you speak publicly of it, I'll deny it and disown you. If you get in any trouble, you'll have to get out of it on your own. There will be times when you will leave Major Thomas and go off on your own to see who I want you to see. I can't provide you government planes or anything like that . . . you'll have to make your own arrangements as you go along. We can't take the chance of having you communicate with me formally while you're gone, but report to me the moment you return.” Codes snatched from the air were all well and good; but this was what FDR enjoyed masterminding, with Vincent Astor, John Franklin Carter, and now his son, secret capers sidestepping government channels.

Secretary of War Stimson, now a convert to codebreaking, worried that the President failed to appreciate Magic adequately. On January 2, 1941, he asked Pa Watson for an appointment with FDR. He found Roosevelt still in bed at 10:30
A.M
., working his way through a basket of pending business. He wanted the President to understand, he said, that Magic offered a window not only on what the Japanese were up to, but also on what was happening inside Germany. The Japanese ambassador to Berlin, General Hiroshi Oshima, was close to Hitler, and proudly and thoroughly reported his conversations with the Führer to his superiors in the Tokyo foreign office through the Purple code. Of this conversation with FDR, Stimson later wrote: “First, I told him that he should read certain of the important reports which had come in from Berlin giving the summary which the Japanese ambassador there had made of the situation and others like it. He hadn't read them.”

FDR began giving greater attention to the Magic intercepts, and through them glimpsed the gulf between what Japan said publicly and what it was doing secretly. Five months after Purple had been broken, on February 14, 1941, Roosevelt welcomed the new Japanese ambassador to Washington, Admiral Kichisaburo Nomura, whom he had known since World War I. As old friends, the two men agreed that they should speak candidly to avert a collision between their nations. But when FDR read the intercepted instructions sent to Nomura by the Japanese foreign minister, Yosuke Matsuoka, he wondered how any honest exchange was possible. He described Matsuoka's messages as “the product of a mind which is deeply disturbed. . . .”

The Japanese had reason to believe that their code had been broken. Dr. Hans Thomsen, the German chargé d'affaires in Washington who had tried to fix the 1940 election, had a line into the State Department's code room. According to the Magic rules, only the secretary, Cordell Hull, was to receive intercepts at State. Hull, however, shared this intelligence with at least six of his top subordinates. One of them, in turn, allowed four more officials in the Far Eastern Division to see the intercepts. With so many recipients, multiple copies had to be run off on a mimeograph machine in the code room. The room's chief was Joseph P. Dugan, an isolationist. What Dugan saw of the Magic intercepts he discussed, even showed, to a like-minded friend. This friend, unknown to Dugan, was in Thomsen's pay. Thus the German diplomat was able to cable Berlin, “As communicated to me by an absolutely reliable source, the State Department is in possession of the key to the Japanese coding system and is, therefore, able to decipher telegrams from Tokyo to Ambassador Nomura. . . .”

On May 6 the Magic codebreakers decrypted a message from Oshima in Berlin relaying what Thomsen had discovered. Thomsen had also alerted Nomura in Washington, and on May 20 the Japanese ambassador reported to Tokyo, “I have discovered that the United States is reading some of our codes though I do not know which ones.” Astonishingly, after a perfunctory investigation, the Japanese concluded that their top ciphers were still unbreakable. Only some of their less important and less secure systems, they concluded, had been penetrated. They continued to send their top-secret diplomatic traffic via Purple, and the President continued to read it via Magic. After the Japanese invaded Indochina in mid-July, FDR slapped an oil and cotton embargo on the country. And because the Japanese continued to use the compromised Purple, he knew almost immediately how far he had pushed Japan. In another intercepted cable to Ambassador Nomura, dated July 31, Tokyo warned, “There is more reason than ever before for us to arm ourselves to the teeth for all-out war.”

Relations between the United States and Japan continued to deteriorate. On October 16 the Konoye government was displaced by the even more bellicose regime of General Hideki Tojo. That October, a Navy month, the Magic decrypts continued to arrive at the President's desk. But in November, an Army month, the traffic stopped, except for Captain Beardall's secondhand summaries. FDR, a man dismissive of bureaucratic channels, particularly foolish contortions generated by interservice rivalries, had had enough. He now demanded to see the full text of Magic intercepts, a seemingly reasonable request by the commander in chief of the nation's armed forces. Beardall uneasily pointed out that November was an Army month in which he was only to give the President summaries. An exasperated FDR told him to bring him all the Magic traffic. After hurried consultations between the Army and Navy, General Miles reluctantly agreed that his service, during its delivery months, would allow the President to see the decrypts. But by now, Roosevelt had tired of the internecine nonsense of Army months and Navy months. Henceforth, he ordered all Magic traffic, in the original, to be delivered to him by Captain Beardall, his naval aide.

While FDR was just beginning to appreciate the value of signals intelligence, Winston Churchill had displayed an absolute hunger for it from the start. The Prime Minister grabbed the red lacquered boxes from his courier's hand and devoured the decrypts inside which were stamped across the top in bold red letters,
ULTRA.
While American cryptographers at Arlington Hall had been wrestling with Purple, eccentrics and a smattering of geniuses at Bletchley Park, Sir Herbert Leon's sprawling estate, had succeeded in breaking the traffic in a cipher system that the Germans considered impenetrable. The radio transmissions of the German military and government ministries were encrypted on a machine called the Enigma. Superficially, the Enigma resembled a portable typewriter with a standard keyboard. The machine had been invented in the 1920s by two German engineers, Arthur Scherbius and Boris Hagelin, for use by business firms wanting to conceal their trade secrets. The name reportedly derived from the convoluted
Enigma
Variations by the English composer Sir Edward Elgar. The machine was first used by German banks and the national railway system; but by 1928, the German army and navy were employing the Enigma to encode classified messages. The Luftwaffe adopted the system in 1935.

The Enigma machine had a space where three or more removable rotors could be placed. In addition, movable wire plugs ran from the machine to an electrical plugboard. Thus, as each letter of a plain language message was being typed, the rotors and the settings of the plugboards caused a different letter to emerge. These settings could be changed, even several times a day, which meant that the possible permutations for each letter became astronomical. With five rotors they reached six sextillion. The Germans calculated that it would take 1,000 codebreakers 900 million years to figure out all the potential key combinations.

The Poles, ever distrustful of their German neighbor, had been attacking the system for years, and in 1932 broke their first Enigma message. However, the ability of the Germans to keep changing rotors and plugboard settings made cracking the Enigma an endless challenge. After Poland was defeated in the fall of 1939, a few Polish cryptanalysts managed to flee to Britain, where they shared their knowledge of Enigma with the Government Code and Cypher School at Bletchley Park. The British quickly took the lead, and by 1940 the park's stately lawns and croquet course had sprouted utilitarian Nissen huts, where mathematicians, physicists, linguists, novelists, chess champions, and Oxford and Cambridge dons labored over Enigma. Among them was Alan Turing, King's College mathematician, whose attack on the system planted the seed for the modern-day computer. One of Turing's colleagues offered a striking definition of the man's genius. Upon hearing an idea hatched by one of his other colleagues, he would say to himself, why hadn't he thought of that? But upon hearing one of Turing's ideas, he concluded that he could never have thought of it. Among Turing's associates were Leonard Palmer, decoder of ancient Minoan and Mycenaean inscriptions, and the offbeat novelist Angus Wilson, once sighted frolicking about the Bletchley swan pool at midnight stark naked.

Ultra was the designation chosen for Enigma messages intercepted and decrypted at Bletchley, the arrival of which so stirred Churchill's anticipation. Wrens, members of the Women's Royal Naval Service, performed most of the work. Eventually, over a thousand of these young women labored among the “bombes,” huge (eight- by eight-foot) electronic contraptions of lights, plugs, wires, and whirring wheels that could solve the Enigma rotor and plugboard settings, and thus enable the cryptanalysts to break the messages. It was a convent-like life for these young women and almost equally monastic for the Bletchley men. The staff, which by war's end, numbered over ten thousand, were quartered in two adjacent RAF bases or crowded into nearby village boardinghouses. So paramount was secrecy that once assigned to Bletchley one could virtually abandon all hope of being reassigned elsewhere. At its peak, the Bletchley staff was decrypting over eighty-four thousand messages every month that the Germans regarded as unbreakable. Churchill demanded to see so much of this traffic that a Mrs. Owens of the Women's Auxiliary Air Force, was assigned full time to do nothing but oversee the PM's Ultra deliveries.

The British were prepared to go to extraordinary lengths to safeguard the secrecy of Ultra. The ultimate example, claimed by writers after the war, supposedly occurred when Churchill, knowing through Ultra that Coventry had been targeted by Luftwaffe bombers, declined to warn the city. Coventry's air defenses, by being ready for an attack, might tip off the Germans that their codes were being broken. Better to sacrifice a city than to compromise Ultra, the reasoning went. Coventry was indeed raided on November 14, 1940, during which the city's center was leveled, its magnificent cathedral destroyed, and over five hundred civilians killed. But the story of Churchill's alleged coldhearted calculus in leaving the city unprepared was untrue. Three days before the raid, Ultra had indeed identified a major Luftwaffe strike, code-named Moonlight Sonata. But the decryption yielded neither the date nor the target. Churchill's intelligence analysts first led him to think that London was to be attacked, and in this mistaken belief, he canceled a trip to the country and ordered his staff to take shelter in a nearby underground station. “You are too young to die,” he told them. Coventry was discovered to be the target just four hours before the Germans struck, but not through Ultra. The RAF had learned how to intercept the Luftwaffe's system for guiding bombers to their destination via radio beams. What doomed Coventry was that the RAF's countermeasure—jamming the beams, thus misleading the German bombers—had used the wrong frequency. Nevertheless, secrecy was a fanatic obsession at Bletchley Park, and the Churchill/Coventry story provided an apocryphal example.

The Americans were eager to share in Britain's codebreaking feats. The British, in the sphere of cryptanalysis, however, believed it better to receive than give. In February 1941 a team of four American cryptographers, led by William Friedman, the dean of U.S. codebreakers, was driven through blacked-out London accompanied by four crates in the back of a truck. The crates contained the components to construct a copy of the machine on which the Japanese enciphered messages in the Purple code. It was a gift for the Government Code and Cypher School. In exchange, their Bletchley counterparts provided the Americans with a few secrets, but revealed nothing of the bombes that enabled them to break into Enigma.

Two reasons account for Britain's unwillingness to be more forthcoming. First, “C,” Stewart Menzies, head of MI6, told Churchill that the Americans “were not as security minded as one would wish.” Thus, while Roosevelt was putting U.S. neutrality on the line by having American ships patrol for British convoys, Menzies was advising the PM against “divulging to the President the information regarding U.S. Naval Units being chased by U Boats.” If the Americans were told which U-boats were pursuing them, they might well deduce that the source of this intelligence was British penetration of German naval codes. It was impossible, Menzies claimed, to “devise any safe means of wrapping up the information in a manner which would not imperil this source [Ultra]. . . .” The second reason the British were reluctant to make the Americans full cryptanalytic partners was more cunning. Among the decrypts delivered daily by Mrs. Owens to Prime Minister Churchill were not only German secrets, but also broken American codes. Britain's eavesdropping on a friend had been going on since the First World War, and it was not something that Churchill could comfortably risk having Roosevelt discover.