War of Shadows

by Gershom Gorenberg

  Then a navy friend asked Reinhard Heydrich to help Rauff out. Heydrich, the unofficial deputy to SS chief Heinrich Himmler, was head of both the Gestapo and the Nazi Party’s intelligence service, known as the SD (for Sicherheitsdienst, “security service”). Both organizations were part of the SS, and they competed in fanaticism in pursuing the Third Reich’s political and “racial” enemies. Heydrich had something in common with Rauff. He, too, had been cashiered from the navy after getting engaged to one woman while having an affair with another. The Nazi Party had given him a new career.16

  In January 1938, Rauff joined the SD. He took off in his new position. He was put in charge of the SD’s mobilization plan for war. He received special dispensation from Himmler to remarry, even though his new wife’s first marriage had been to a Jew. He’d vaguely sympathized with National Socialism, but his first loyalty had been to the navy till it threw him out. Now he gave his everything to the Führer and the discipline of the SD.

  A later US intelligence report describes Rauff as “medium height, clear white skin, blue eyes.”17 It might as well say “generic SS officer.”18 A purported “Aryan body” was a prerequisite for the job. In a photograph from his early SD days, he has been given back his navy uniform. He has a wide face, a cleft chin, and a straight, expressionless mouth.19

  Heydrich’s deputy, Werner Best, presided over the early-September meeting with Rauff and five other division heads at SS Main Office, and laid out the plans for the subjugation of Poland. Germany would annex much of the western part of the country and put the rest under its direct rule. The goal was to expel Jews and Poles from the annexed areas to the Polish reserve further east.20

  Werner Best didn’t need to go into the plans for settling Germans in the Lebensraum of the East. The job of the SS was to clear the space. But Nazi bureaucrats did have a model in mind that they had closely studied: Italy’s colonization of Libya and Ethiopia. Nazis were impressed that their Fascist ally was turning its African empire into “white man’s country.” The colonial effort built the “warrior spirit,” and by mixing Italians from all parts of the country in its settlements, it created a new and better “racial type.” Germany would subjugate the Poles as Italy did Arabs and Ethiopians. To the Italian blueprint, the Nazis added an innovation: eliminating the Jews.21

  The SS forum met the next week with Heydrich, and the week after. Hitler had approved more detailed plans. In the short term, Jews would be consigned to ghettos until they could be expelled. There would be three categories of Poles in the annexed territories—political leaders, to be put in concentration camps; mid-level Poles, to be deported immediately; and all the rest, who would first be exploited as laborers, then pushed eastward. If mass murder was not yet the main theme, it was a very clear motif.22

  Until now, Rauff might have been a Nazi bureaucrat as a solution to his career problems. From this point, “his participation in the inner circle of decision makers… marked a break, in which Rauff transformed himself from a possible follower to a perpetrator.”23

  THE ORDER TO leave Warsaw came on September 5. By the next day, Marian Rejewski and his colleagues closed down the German Section of the Polish military’s Cipher Office, and were listening to the rhythmic click of train wheels on their way to Brest in eastern Poland. From there they zigzagged southward, seeking sanctuary, to the small town of Wlodzimierz Wolynski.24 They got out of the capital with very little time to spare. Germany had plunged its armies into Poland like swords from the north, west, and south. By September 8, German tanks were on the outskirts of Warsaw, the heart of Poland.25

  Rejewski was carrying a secret weapon. Indeed, it would be better to say that he was Poland’s secret weapon.

  Photos of Rejewski show a man with thick hair combed back from his round face. He wears small circular glasses over smiling eyes.26 On the train, he surely wasn’t smiling. Besides being in danger himself, he had been forced to leave his wife, his three-year-old son, and his infant daughter in Warsaw.

  Ten years before, when Rejewski was writing his master’s thesis in mathematics at Poznań University, another student had come up to him and said that the department head had put him down on a list for a meeting. The students, it turned out, had been selected by the Intelligence Section of the Polish General Staff. They were invited to a course in codebreaking, held in a fort in the city. Poznań had been under German rule until the Great War, so it was a good place to recruit German-speaking Poles. By 1931, Rejewski was working for the Cipher Office, at first part-time in Poznań, then full-time in Warsaw. He was assigned the bureau’s greatest challenge. Two even younger mathematicians, Jerzy Rozycki and Henryk Zygalski, soon joined him.27 They, too, were on the train out of Warsaw.

  The test of the codebreaker begins with the problem facing the code maker: how to send a message that can only be read by the person it’s intended for. One solution is to replace each word with something else—for instance, a random group of five letters or numbers. “Warsaw” could be 36504 or YKRBI; “tomorrow” could be 85327 or MQMYT. The sender finds each word in the codebook and writes down the group; the receiver uses the opposite side of the book, which lists code groups and their plain-language meaning.

  One risk is that your rival might get a copy of the codebook—delivered by a spy, or stolen from a diplomat’s hotel room, or captured in the headquarters of an enemy unit. The professional term for this is “physical compromise,” which sounds like an entirely different kind of espionage. Nearly as good is to get hold of a message both in its plain-language and coded form. Line them up, and you have a piece of the codebook.

  Even without such glitches, if you send many messages in the same code, especially about a known subject, a skilled codebreaker can look for repetitions, think of possible meanings, see if they fit together into sentences, and begin to piece together the codebook. One of Rejewski’s first assignments was cracking a German naval code. “You just… keep manipulating the material over and over again, you see, and you look [at it] and make guesses—it’s a little like… crossword puzzles, like riddles, you have to figure out what this [code] group could mean,” Rejewski would later explain.28 Solving a code requires marathon patience. It requires holding a huge amount of information in your head, and extraordinary reasoning ability, and something beyond reason—sudden flashes of intuition, sparks leaping between two charged points in the clouds of half-consciousness.

  A standard way to protect a code was to make the groups look different each time. For a code that gave groups of numbers, you could provide another long table of random numbers. The sender’s code clerk added the first random number to the code group for the first word, the second random number to the second group, and so forth. The receiving clerk took the same list and subtracted the numbers. For the next message, they could start at a different, mutually agreed point on the list.

  Like the codebook itself, the subtraction table—the list of random numbers—lost its value the moment it fell into enemy hands. Besides that, the method was cumbersome, slow, and prone to mistakes, especially in messages sent by soldiers on the battlefield while shells were falling. (June Watkins of the Women’s Auxiliary Air Force would learn this about subtraction tables in her code officers’ course in Cairo, and use them in the basement of the Metropole Hotel—and she would complain in code-room slang that the “gremlins have certainly been at work” when messages arrived garbled from units in the desert.29)

  The alternative to a code is a cipher—replacing each letter of the original text with another letter. To hide the original words and create what looks like code groups, you take out all the spaces, spell out punctuation, and divide the text into groups of five.

  A simple cipher, though, can be broken in minutes if the codebreaker has a long enough message. The most common letter in English is e. If replaced by z, then z will be the most common letter in the enciphered message. Code writers came up with methods to overcome this. But those techniques slowed up the process of enciphering and
deciphering. Sometimes they did little but increase the number of messages that a codebreaker needed in order to break in.

  But what if the code clerk sending a message could use a different cipher for every letter? What if you typed “EEEEE,” and it came out “YBNWQ,” and so on, an apparently unconnected stream of letters, ad infinitum? A would-be codebreaker looking for the most common letter in this message would be lost. To have any value, of course, the receiving clerk would need to have the same cipher for each letter. Yet the method would have to be quick and easy to use.

  The new era of telegraph and radio made the need for a convenient but unbreakable code much more pressing, for businesses as for governments. Messages sent by Morse code in electrical pulses could too easily be read by the wrong people. Who knew who might be working at the cable company, or who might listen in, uninvited, to wireless transmissions? Say, for instance, you were at the Marconi Radiotelegraph Company office on El Madabegh Street in central Cairo, sending your partner in Buenos Aires a particularly attractive offer you’d gotten for a consignment of cotton. Would you want the message to fall into the hands of a competitor?

  “If you have no good coding system, you are always running a considerable risk. Transmitted by cable or without wire, your correspondence will always be exposed to every spy… your intended or settled contracts, your offers and important news to every inquisitive eye,” read a mid-1920s sales brochure from the Chiffriermaschinen (Cipher Machines) company of Berlin, advertising its new business device, the Enigma.30

  The pamphlet showed something that looked like a close relative of the typewriter, sitting in a wooden box. The keyboard had twenty-six keys, for letters only. Behind the keyboard was a lamp board showing the letters of the alphabet, arranged in the same pattern as on the keyboard, each with a tiny electric light under it. At the back, instead of a place for paper, three toothed wheels stuck out of a lid. With the oak box and the battery, the whole thing weighed under fifteen pounds.31

  Hidden inside each wheel was a web of wiring. The Enigma’s German inventor, Arthur Scherbius, designed his machine so that each time you typed a letter, a pulse of electricity followed a tangled path through all three wheels and lit up one of the letters on the lamp board. A second clerk would watch and write down the letters as they lit up, creating the enciphered message. To write a number or punctuation mark, you spelled it out.

  Hitting a key also made one of the wheels in back move a notch. Twenty-six keystrokes made it come full circle—and move the next wheel one notch. When the first wheel did another full circle, it moved the second wheel one more notch. When the second wheel went all the way around, it moved the third wheel once. It took over seventeen thousand keystrokes to bring all three wheels back to their original positions.

  Since the wheels kept moving, the path changed each time you hit a key. Every position created a different cipher. If you typed “ZZZ,” it might come out as “WMY” or “UGB.” The one certainty on an Enigma was that Z would never come out as Z.

  The elegant thing about Scherbius’s code-department-in-a-box was that it worked both ways. If the clerk at the receiving end set the machine to the exact same starting position and typed in the meaningless string of letters she’d received, the original message appeared, one letter at a time, flashing from the little lights. At any other setting, the message remained a mystery. In the original design, there were close to two billion possible settings.32

  In 1926, the navy of the Weimar Republic began using Enigma machines for its communications, followed by the German army in 1928. Nazi Germany’s air force, the Luftwaffe, adopted the machine in 1935.33 Other inventors created cipher machines in those years, but they were big and bulky—fine for embassies or stationary military headquarters. Enigma was perfectly suited for the new, fast-moving warfare that Germany was developing.

  The German military upgraded Enigma in a way that upped the possible settings into the quintillions. This was actually a small number compared to the total possible ways to wire three different wheels. Rejewski would calculate that this came out to a number written as five, followed by ninety-two zeroes, a quantity beyond imagination.34 The wires were the riddle wrapped inside the Enigma.

  Obviously, no codebreaker was ever going to look at messages and figure out the wiring—not in a trillion years.

  Rejewski did it in less than three months. No one else ever matched the feat.

  He started working on the equations in the autumn of 1932, and solved the puzzle of the wiring by January 1933. Rozycki and Zygalski joined him to work on discovering the daily settings. By the time Hitler came to power in 1933, they could read every German military message that a Polish radio man at an interception station, straining to listen for Morse dots and dashes on the right frequency, could write down.35

  The Warsaw office in which Rejewski and his two colleagues worked was on the third floor of an eighteenth-century Polish castle that had become the Polish General Staff building. From their window, they could look out at the Tomb of the Unknown Soldier. Diplomatic protocol required foreign dignitaries on official visits to pay respects at the tomb. The codebreakers could watch German foreign minister Joachim von Ribbentrop or Hitler’s personal emissary Hermann Göring lay their wreaths without ever suspecting that three young mathematicians had found a back door to the Third Reich’s military secrets.36

  As Germany prepared for war, it kept adding twists to how it used Enigma to make it even more secure. Rejewski and his two coworkers kept breaking in. The job got more time-consuming, and there were only three of them.37 The information they gleaned could not make up for Poland’s military weakness. And the radio messages did not include the final betrayal—the secret provisions of the Molotov-Ribbentrop Pact between the Soviet Union and Germany, signed a week before Germany invaded Poland.

  On September 17, under those provisions, the Soviet Union invaded eastern Poland. Rejewski and the rest of the German Section fled again, this time southward by truck to the Romanian border. Evading an internment camp, Rejewski, Rozycki, and Zygalski reached Bucharest and came to the British legation for help. A diplomat told them he’d have to check with London first.

  The three Poles didn’t want to take the chance of waiting in a city where they weren’t supposed to be. They headed for the French embassy. French intelligence knew them. The embassy gave them passports, visas, and tickets, and they boarded yet another train—this time across the southern rim of Europe, through Yugoslavia and Italy to France.38

  Poland was doomed, but its secret weapon had escaped with his life.

  2

  THE SEDUCTIVE CURVES OF THE DUNES

  September 1939. London–Cairo–Gilf Kebir.

  THE TROOPSHIP HAD been a luxury liner till war broke out. Ralph Bagnold had been a civilian. Now Bagnold was back in the Royal Engineers uniform he’d worn nearly half his life, with the major’s insignia on his shoulders, heading out yet again for a corner of the British Empire.

  By the imperturbable unreason of the military, though, his destination was East Africa, rather than Egypt.1 Bagnold knew the empty stretches of Egypt as well as any man alive, with the possible competition of Laszlo Almasy, the ambiguous Hungarian explorer.

  Bagnold had followed his father into the Royal Engineers. He made officer by age nineteen, sped along by the voracious hunger of the Great War. After surviving the trenches, he completed a three-year degree in engineering at Cambridge in two years and returned to the military.2 In 1926 he arrived in Cairo with his two-seater Morris automobile—Bagnold liked cars—to join the signal corps of the BTE, the British Troops in Egypt.3

  The BTE was a minor military appendage of the empire, with little to do unless a rebellion broke out against the Egyptian government or against Britain’s role in ruling the country. If you wanted no more than to play polo at the Gezira Sporting Club on its island in the Nile, Cairo was a fine posting.

  Bagnold was bored. No one ever left the Nile Valley for the desert on either side. A
fellow lieutenant bought a Model T, and Bagnold bought one like it, since his Morris wasn’t built for roadless rock and sand. They started with several forays eastward. On a map of Transjordan, Bagnold saw the name Petra, the legendary ruins of a city that the ancient Nabateans had carved, not built, out of the walls of a red rock canyon. So he and his friend drove there on an untried route through the Sinai, with four other young officers to help push the cars out of sand when they got stuck. Bagnold was falling in love—with taking off with five other fellows and three cars to drive a thousand miles across land no one had ever driven, with the absolute silence of the desert night, with the “secret joy” of crawling beneath the car in mid-desert to change a broken spring with his own grease-covered hands.4

  On the other side of the Nile lay terrain far harsher. Bagnold wanted to go there. The part of the Sahara known as the Libyan Desert stretched a thousand miles westward from the river, and a thousand miles from the Mediterranean southward. Herodotus wrote of the Persian army of fifty thousand men, sent by Cambyses, son of Cyrus the Great, which marched into the desert and was swallowed entirely by a sandstorm.5 In the 1920s much of the desert was blank space on maps, calling seductively to explorers.

  Kemal el Din, a millionaire Egyptian prince and cousin to the future King Farouk, ventured into the desert with cars riding half on wheels, half on caterpillar tracks. At the southwest corner of Egypt, near the border with Libya, he discovered a sandstone tableland the size of Switzerland rising out of the desert. He named it the Great Plateau, Gilf Kebir. The Great Sand Sea, a region of dunes hundreds of miles wide, ran from Gilf Kebir nearly to the Mediterranean. Together they created a barrier between Libya and Egypt much more substantive than the border that European diplomats had drawn on a map with a ruler. The waves of the Sand Sea were slow-moving sand dunes, as high as three hundred feet. The nineteenth-century explorer who named it concluded that his camels would never make it across the dunes. Kemal el Din reached the same conclusion about his half-tracks.6