THE CODEBREAKERS

by DAVID KAHN

  The danger to the Allies did not come from any possible future solutions, since new sets of rotors were issued almost immediately. Rather it came from the past. Eisenhower and his high subordinates had been directing the greatest campaign in all history by streams of ABA-sheathed messages. These were all based upon the well-matured plans of high strategy. The past traffic dealing with supplies alone would tell the Germans a great deal about Allied potentialities, since modern war is, to a very considerable degree, a conflict of logistics. If the Germans could translate their back files of intercepts with the missing ABA, they could obtain a profound insight into the broad guidelines on which the Allies were conducting the war in Western Europe. Nor could the Allies easily reshape these plans, for mountains of supplies and millions of men had been moved to conform with them. Thus, given intelligence of this high order, and the massive irreversible momentum of modern war, the Germans might well counter Allied moves so effectively as to add months to the war and thousands of lives to its toll.

  None of this was lost on Eisenhower. He personally pressed the commander of his 6th Army Group, General Jacob L. Devers, to find the missing safes at all costs, and Devers assigned the task to his group’s chief counterintelligence officer, Colonel David G. Erskine.

  Erskine began by sending out feelers to anti-Nazi German spies in Switzerland to find out if the Nazis had been congratulating themselves on some extraordinary feat recently. Then he spread discreet queries through the 6th Army Group’s area to determine if anyone knew anything about a missing truck bearing three safes containing “highly classified documents.” Perhaps a French civilian or an American soldier had appropriated the truck without knowing of its precious cargo. Any American finding the truck, or the safes, or both, Erskine announced, would get that coveted reward: home leave. No one claimed it.

  Erskine sent L-5 liaison planes skimming low over Alsace, but their pilots spotted no abandoned trucks. So every unit commander in the 6th Army Group was ordered to personally check the serial numbers of every one of his vehicles against that of the missing truck. Nothing. The search was extended over most of the front. Military policemen checked vehicles at roadblocks; canals were drained; informants were checked. The mystery just deepened. Repeatedly, Eisenhower asked Devers, and Devers daily asked Erskine, whether the missing ABA had been found.

  After three weeks of intensive but fruitless search, a special squad of American and French counterintelligence agents was formed to concentrate solely on the loss. In charge was Lieutenant Grant Heilman, a tall, blond Pennsylvanian. His operation got off to an embarrassing start when two jeeps parked outside his headquarters disappeared as mysteriously as had the truck. But it picked up when Eisenhower sent a two-star general, Fay B. Prickett, to Colmar to lend authority to the search. Heilman checked everything, including shelled trucks abandoned at the bridge over the Rhine. Erskine’s Swiss spies returned negative reports, and his hunch that French intelligence might have taken the ABA to improve their own cryptology—checked with no less a personage than General Charles de Gaulle, head of the provisional government—did not pan out.

  Suddenly, when no more clues could be discerned, Erskine got a tip from a French source. Rushing to a sizable creek called the Giessen River near the town of Sélèstat, not far from Colmar, he saw, lying in the mud, two of the missing 300-pound safes. It seemed likely that they had been dumped into the Giessen from a masonry bridge about a hundred yards upstream from where they had been found and had been rolled downstream by the strong current. Erskine immediately ordered a search of the banks for the third safe. They were barren.

  Divers were brought in from Cherbourg to examine the stream bed. They found nothing. Erskine decided to dam the stream and dredge the bottom with a bulldozer. In three days the dam was built and the bottom scoured—with no luck. Heilman, feeling hopeless, began to search the muddy portion of the bed that the falling waters had exposed. Suddenly something metallic glinted in the sun. He rushed over—and found his own buried treasure. It was the missing safe. Both its handles had been knocked off by rocks, but otherwise it appeared, on checking by Signal Corps officers, to be intact.

  Thus, on March 20, the search for the missing SIGABA ended, six frantic weeks after it had begun. Erskine, checking again with the French, this time on an I-don’t-want-anyone-punished basis, discovered that a French military chauffeur who had lost his truck in Colmar “borrowed” the American one while the sergeants were in the brothel, and, afraid that he might be accused of stealing the safes, pushed them off the bridge into the Giessen. This ruled out the possibility that the secret mechanism had ever been in the hands of the enemy.

  Heilman was promoted to captain. Both he and Erskine were awarded the Bronze Star. Uncounted man-hours had been squandered in the search and an unknown toll of nervous energy taken. But the precious messages were safe, and with them the plans that within a few more weeks directed the Allies to victory.

  * The British also read Spanish diplomatic traffic between Washington and Madrid from early 1942 to the end of the war, thanks to B.S.C.’s photographing of Spain’s diplomatic code. This it accomplished with the help of a Basque leader who had exiled himself after the Falangist victory, and a Basque janitor and an anti-Franco typist at the Spanish embassy in Washington. B.S.C. also photographed Spanish codebooks in Caracas in October, 1942.

  16

  CENSORS, SCRAMBLERS, AND SPIES

  CIPHER IS THE LANGUAGE OF SPIES—and usually they must talk in whispers. A spy’s success, his very existence, depends on his not being seen or heard. Sending messages in obviously cryptographic form would alert counterespionage to him as effectively as wearing a cloak and dagger. Yet he must transmit, else he is useless. So he eschews the overt methods of secret communications for the covert. He resorts to open codes, hollow heels, invisible inks, microscopically small missives—the steganographic methods that conceal the very fact that a message is being sent. He seeks to communicate unnoticed.

  And to block this very attempt and root out the enemy within, governments erect great filters at their mail and cable ports of entry to prevent and detect these clandestine communications. These sieves, which let innocent messages flow through, are the censorship organizations.

  Descended in a sense from the black chambers of the 1700s, they are creatures of war in democracies and of tyranny in dictatorships. Censorship first sprang up on a major scale in World War I, and the lessons that Britain learned then she put to good use twenty years later when she again filtered communications. Even before the United States entered the war, British censorship had caught two major German spies in the United States and its protectorate of Cuba.

  In December, 1940, one of the 1,200 examiners that British censorship had installed in the commodious Princess Hotel in Bermuda stopped a letter addressed to Berlin from New York. He suspected it because it described a list of Allied shipping and used several expressions—such as “cannon” for “guns” in describing the vessels’ armament—that suggested the writer might be German and a possible Nazi agent. The letter was signed “Joe K.” A watch set up for more letters with his handwriting soon picked out quite a few more, mostly to Spain and Portugal. Their language seemed slightly forced, and a team began studying the letters to see whether this indicated an open code and, if so, what the real meaning was.

  One member of the team was a persistent young woman named Nadya Gardner, who became convinced that the letters contained invisible writing. The usual strip tests with chemicals that bring out the ordinary secret inks gave negative results, but Miss Gardner persisted. Finally the chemists, under Dr. Enrique Dent, applied the iodine-vapor test invented back in World War I—and to their surprise secret writing did appear on the back of the typed sheets. The letter of April 15, 1941, addressed to Mr. Manuel Alonso, Apartado 718, Madrid, carried on the back of its two pages a list of ships then docked at New York: “On April 14 was at pier 97 (Manhattan) the Norwegian M. S. Tain Shan—6601 tons—gray superstr # at pier 90
was a Dutch freighter ….” A letter of six days later, addressed to a Miss Isabel Machado Santos in Lisbon, reported in invisible ink that “British have about 70,000 men on Iceland # The S.S. Ville de Liege was sunk about April 14—many thanks # Types of airplanes flown to England (continued from letter 69)-3. Boeing B-17C (model 299T) twenty were released by the U.S. Army to Britain on Nov 20 ….” These little billets-doux were written in a solution of pyramidon, a powder often used as a headache cure and readily obtainable at most pharmacies.

  But there was still no clue as to the sender. The letters bore no return address, and it was rather unlikely that “Joe K” was the spy’s real first name and last initial. Finally, British censorship picked out another Joe K letter that reported that “Phil” had been fatally injured in a New York traffic accident on March 18 and had died at St. Vincent’s Hospital. F.B.I. agents found that the man in the accident was known as Julio Lopez Lido, and that witnesses had seen that a man with Lido had grabbed his briefcase after the accident and hurried away. Eventually, the agents learned that Lido’s true name was Ulrich von der Osten and that the writer of the Joe K letters was Kurt Frederick Ludwig. Ludwig, born in Ohio but raised in Germany, had come to the United States in March of 1940 to organize a spy ring, which he had done with moderate success.

  When captured, he had several bottles of pyramidon in his possession. The odd tone of the open text of his letters was accounted for by its double meanings. “Your order 5 is rather large—and I with my limited facilities and funds shall never be able to fill such an immense order completely,” he wrote to one of his addressees—all of them, incidentally, cover addresses for Himmler. This message really meant that he would have difficulty fulfilling the instructions sent him in communication No. 5 because of too few agents and too little money. Ludwig was convicted in the U.S. District Court at Brooklyn.

  The second spy trapped by the alert Bermuda station went to his death. On a November day in 1941, an alert censor detected a rather Germanic cast to the handwriting in a Spanish-language letter from Havana to Lisbon and sent it over for a routine test for secret ink. His intuition was confirmed when a long missive appeared, listing ships being loaded in Havana harbor and discussing an airfield being constructed. The examiners were alerted to watch for similar handwriting. The next letter turned up a few days later. Censorship continued picking out these letters, which recited details of merchant shipping in Cuban waters and of the enlargement of the U.S. Navy’s base at Guantánamo Bay, until the writer’s real Havana address showed up in secret ink. Letters posted to this address were watched, and on September 5, 1942, after sufficient evidence had been amassed, police arrested “R. Castillo,” who proved to be Heinz August Luning. He had been sent to Havana from Germany in September, 1941, and of the 48 letters he had sent to Europe, the Bermuda censors had intercepted all but five. On November 9, 1942, he went before a firing squad at Principe Fortress, the first man in Cuba to be executed as a spy.

  Soon after Pearl Harbor, the United States built up a censorship service that began in the borrowed office in which Byron Price went to work as Chief Censor and grew to an organization whose 14,462 examiners occupied 90 buildings throughout the country, opened a million pieces of overseas mail a day, listened to innumerable telephone conversations, and scanned movies, magazines, and radio scripts. Millions became familiar with the “Opened by Censor” sticker and the scissored letter.

  To plug up as many steganographic channels of communication as possible, the Office of Censorship banned in advance the sending of whole classes of objects or kinds of messages. International chess games by mail were stopped. Crossword puzzles were extracted from letters, for the examiners did not have time to solve them to see if they concealed a secret message, and so were newspaper clippings, which might have spelled out messages by dotting successive letters with secret ink—a modern version of a system described more than 2,000 years earlier by Aeneas the Tactician. Listing of students’ grades was tabooed. One letter containing knitting instructions was held up long enough for an examiner to knit a sweater to see if the given sequence of knit two and cast off contained a hidden message like that of Madame Defarge, who knitted into her “shrouds” the names of further enemies of the French Republic, “whose lives the guillotine then surely swallowed up.” A stamp bank was maintained at each censorship station; examiners removed loose stamps, which might spell out a code message, and replaced them with others of equal value, but of different number and denomination. Blank paper, often sent from the United States to relatives in paper-short countries, was similarly replaced from a paper bank to obviate secret-ink transmissions. Childish scrawls, sent from proud parents to proud grandparents, were removed because of the possibility of their covering a map. Even lovers’ X’s, meant as kisses, were heartlessly deleted if censors thought they might be a code.

  Censorship cable regulations prohibited sending any text that was unclear to the censor, including numbers unrelated to the text or a personal note in a business communication, and that was not in English, French, Spanish, or Portuguese plain language. To kill any possible sub rosa message, censors sometimes paraphrased messages. This practice gave rise to Censorship’s classic tale, which dates back to World War I. Onto the desk of a censor was placed the cablegram Father is dead. The censor considered it briefly, changed it to Father is deceased, and forwarded it. Soon thereafter the reply appeared on his desk: Is Father dead or deceased?

  Cables ordering flowers—“Deliver three white orchids to my wife Saturday”—offered so blatant an invitation to clandestine communication that the censors forbade naming the kind of flower and the date of delivery, leaving both up to the individual florist. Later in the war, all international flower messages were prohibited by the United States and Great Britain because of the danger of their masking signals. Only those between the U.S. and her territories and between the U.S., Canada, and Mexico were permitted. The censorship permitted only nine of the most widely used commercial codes, and every coded message had to include an indicating abbreviation in its preamble. A firm could not use its private code without a special license from the director of censorship, who required that fifteen copies of the code-book be furnished for use by the censors.*

  Precautions were taken with the mass media, too. Newspapers were warned to be careful in taking want ads. Prevention was directed mainly at commercial radio, which could instantaneously deliver open-code secret messages to listening submarines or enemy agents with the greatest of ease. Such possibilities had been driven home forcefully to the broadcasting industry a year before Pearl Harbor in a test conducted by a military intelligence officer. By having an announcer mention England’s Queen Elizabeth, the officer wove into an interview with former heavyweight champion Max Baer the hidden message: S-112: Queen Elizabeth sails tonight with hundreds of airplanes for Halifax. What was disturbing was that neither the announcer, the station manager, Baer, nor any of the thousands of listeners on the nationwide hook-up except those who had been initiated into the secret were aware that the message had been broadcast. With this in mind, the Office of Censorship ruled that telephone or telegraph requests for phonograph records were not to be honored, and that mail requests must be held for an irregular, unspecified time before playing. This would defeat any attempts to have “Jersey Bounce” tell a waiting U-boat that Convoy sails today. The same situation applied to the personal ads, such as for lost dogs, that local stations broadcast. Halted completely were man-in-the-street interviews and Santa Claus lists of toys that children wanted.

  Preventive censorship like this was only half the job, however. It could not be expected that spies would limit themselves to such easily confounded methods of communication. The other half of the job was the detection of the other methods that they might use. To sharpen Censorship’s spy-catching tools by coordinating and assisting the field stations that spotted the hidden messages and by improving liaison with counterespionage agencies like the F.B.I., Price in May of 1943 establi
shed the Technical Operations Division at headquarters, appointing Lieutenant Colonel Harold R. Shaw as its chief and an assistant director in the Office of Censorship. Shaw, 39, son of a Regular Army officer, had been commissioned in the Army Reserve upon his graduation from the University of Hawaii. He maintained a strong interest in military intelligence while working in soil physics and chemistry and hydraulics as irrigation superintendent of a large sugar plantation on Oahu. In the fall of 1941, after being called to active duty, he had taken an intensive two-month course with 14 other reservists who would serve as the nucleus of a postal censorship in case of war. The training was conducted by Major W. P. (Red) Corderman in a three-story brick office building in Clarendon, Virginia, a sleepy suburb of Washington; one of the most frequent lecturers was William F. Friedman. Across the street a group of Navy Reserve officers under Captain Herbert K. Fenn was similarly planning the details for cable and radio censorship. Fenn, a World War I base censor and a Navy communications expert, later became Chief Cable Censor. One of Shaw’s classmates, Norman V. Carlson, president of a San Francisco movie-camera firm, early in the war replaced Corderman as Chief Postal Censor. With the outbreak of war, Shaw rushed back to Hawaii to become District Postal Censor and Chief Military Censor. Price recalled him from there to head the Technical Operations Division.

  T.O.D. was quartered in the Federal Trade Commission Building, the three-sided structure that housed the Office of Censorship at Pennsylvania and Constitution avenues in Washington. Shaw administered it from Room 509 with three assistants and a secretarial staff. Two technical sections operated under maximum security in a windowless, guarded area on the seventh, or top, floor. The laboratory was headed by Dr. Elwood C. Pierce, a biochemist at the University of Indiana who had joined Censorship at the start of the war. He and his assistant, Dr. Willard Breon of the University of Maryland chemistry faculty, had prepared a manual on detection of secret inks, trained key personnel of the censorship field stations in laboratory operation, and handled some of the more active and difficult cases themselves. From Hawaii Shaw imported his trusted cryptanalytic expert to form a unit “capable,” he said, “not only of cracking codes and ciphers but also of building the intricate dossiers of personal history, contacts, handwriting peculiarities, and correspondence habits of each actual and suspected espionage agent.” The man who could do it was Armen Abdian, a former New Englander who had come to Hawaii in the prewar Army, had taught a cram course for prospective West Pointers, and had gone into business in Honolulu.