The Codebreakers: The True Story of the Secret Intelligence Team That Changed the Course of the First World War (37 page)

Choctaw soldiers

True to his training and persona, Pershing, his hair gone grey and his face lined with grief, soldiered on, drawing on his vast reserve of experience and support. Indeed, President Teddy Roosevelt had thought so highly of Pershing’s military skills in the Spanish—American War that he wanted him promoted from lieutenant to colonel in 1903. Since the US army only promoted by seniority, Pershing was out of luck until Roosevelt pulled rank of his own in 1905. The President couldn’t promote a captain to colonel, but he could make any man a general, and so he promoted then Captain Pershing to brigadier general, leapfrogging him three ranks, and past 832 senior officers.

Pershing had learned the value of stealth and secrecy in his hunt for Pancho Villa, and while that mission had ended in failure to achieve its objective, he brought with him in the first AEF wave many of the men who had fought in that campaign, and a profound belief in the need for a vast and deep intelligence network.

Pershing knew that the American military intelligence was at best at the back of a very sophisticated class, and at worst scorned by the Allies as yet another liability brought to the war by the still undertrained, undersupplied United States army, whose commander stubbornly insisted on keeping them together as a unit rather than loaning them to the French and British as replacement troops.

The First World War proved to be a revolutionary event for American intelligence, with the exigencies of an army in the field creating the dynamic and necessary conditions for the Americans to fully commit to the world of military intelligence. The man Pershing picked to create his field intelligence programme had served as his adjutant general in the Philippine—American War, and was twice cited for gallantry in the Spanish—American War, but at heart, Dennis E. Nolan was a football coach.

Born in 1872, the eldest of six children of Irish immigrants, Nolan grew up with the classic American trifecta of hard work, faith in God, and love of country as the keys to success. He graduated from the United States Military Academy at West Point in 1896, where his talents on both offence and defence at football earned him the coveted All-American award of excellence, and those with the bat and glove won him his varsity letter playing baseball. After serving in the field with Pershing, Nolan married the niece of American Civil War Union General Ulysses S. Grant, then returned to West Point to coach the 1902 football team to a 6-1-1 record (they beat Navy but lost to Harvard) and to teach history until being called to Washington to become part of the US army’s first General Staff.

Dennis Nolan, now a Colonel, in May 1918

By July 1917, Pershing had followed the French model and organised the AEF staff into four equal units: G1 was Personnel, G2 Intelligence, G3 Operations and G4 Supply. The intelligence service took its prefix ‘G’ from the British and ‘2’ from the French intelligence Deuxième Bureau. In the summer of 1917, Major Nolan borrowed more from the British, particularly their system for tactical support. Pershing directed that intelligence units should exist at all levels of the AEF, so Nolan created an intelligence presence from the top of the army, which at its largest in August 1918 had 1.3 million troops, down to the AEF’s smallest unit, the squad, which consisted of between four and ten soldiers. At field grade, the intelligence units were known as S2.

Nolan also realised that he needed another kind of intelligence, which came down to the reality of fighting a foreign war: he needed French speakers to protect his soldiers from enemy espionage and subversion. In July, 1917, he requested ‘fifty secret service men, who have had training in police work [and] who speak French fluently, be enlisted as sergeants of infantry in service in intelligence work and sent to France at an early date. As these men will be in intimate relation with the French people, it is a matter of great importance that they not only speak the language but are men of high character.’

A French-speaking officer with experience in police work was dispatched to New Orleans and New York City to find 50 French speakers who were willing to do intelligence work in France. He put advertisements in local newspapers and accepted those who could pass the army’s physical examination and answer a few simple questions in French.

The first wave of men aiming to be Intelligence Police, as might be expected, were a diverse lot, and not always of ‘high character’. They included a French Foreign Legion deserter (and murderer), a Russian train robber, a deposed Belgian nobleman, as well as a few French army deserters. By the end of the war, the Intelligence Police were 418 strong, and one of their group, Sergeant Peter Pasqua, a Portuguese immigrant to the USA and master of languages, became the first Intelligence Police agent to win the newly created Citation for Meritorious Service after successfully infiltrating and disrupting a group of Spanish subversives working for a German agent.

At field level, intelligence-gathering involved everything from interrogating prisoners, to interpreting aerial reconnaissance, to watching the movement of enemy units on trains – in order to parse their upcoming order of battle – to espionage, to anything else that would help command to understand what the enemy was doing on the ground. Of course, there was also all the information that passed through the air: Nolan appointed Major Frank Moorman to head G2-A6, the Radio Intelligence Section, whose job was to intercept German messages and decode them, as well as to send American communiqués as securely as possible.

Moorman was a 40-year-old blunt-speaking career army man from Michigan who had risen from private to major, and had graduated from the Army Signals School in 1915. In September 1917, Pershing moved his GHQ to Chaumont, a hilltop city in the valley of the Marne, about 150 miles south-east of Paris. It was there that the AEF created its own Room 40, though theirs was called, perhaps with irony, the Glass House, and was housed in a single-storey concrete and glass shack hidden behind one of the main barracks buildings, near the sheds that contained the commissary stores.

Inside was the eclectic brainpower of the codebreakers of G2-A6, who were divided into four sections: traffic analysis, cryptanalysis, telephone intercept of enemy air artillery spotters, and the Security Service. Enlisted men were selected not because they knew codes and how to break them, but because they knew German and had potential, displayed by their application of logic and rigour to other disciplines. One officer was a lawyer who had become an expert in archaeology; another a chess master; another was an architect who had spent years learning Hebrew, Farsi and other Oriental languages.

The codebreakers were isolated from the other men by choice and, after one or two indiscretions, by necessity. Indeed, Major Moorman had established the Security Service with four stations to monitor American radio and telephone transmissions and to report any offending breaches to prevent disaster. ‘There certainly never existed on the Western Front a force more negligent in the use of their own code than was the American army,’ Moorman later recalled, but then, the American army codes were often the problem. It was something that Herbert Yardley, the original MI-8 codesmith, was about to find out the hard way.

When Captain Herbert Yardley, America’s leading codebreaker, arrived in London in August 1918 on the orders of General Pershing, he came with the swagger of having seen the USA’s cryptographic unit, MI-8, grow from a staff of himself and two civilian employees to nearly 200 men and women working to save America from her encoded enemies. He also had his own natural swagger, one born of naiveté and robust self-belief, so he was nonplussed when the British didn’t immediately open their code vault and share everything with him. ‘For days I made no progress,’ he recalled, but ‘I consumed a great deal of tea and drank quantities of whisky and soda with various officers in the War Office. They were affable enough, and invited me to their clubs. But I received no information.’ Doubly frustrating was the fact that Yardley – or the US taxpayer – was often footing the bill for this British hospitality. Yardley’s dinner for himself and five British officers at the Ritz Hotel cost £5 14s 6d – or about £250 in today’s currency.

Pershing had ordered Yardley to London to learn as much as he could from the British codemasters, but Blinker Hall didn’t like the American, pegging him as a talkative braggart, and wouldn’t let him anywhere near Room 40. Part of Yardley’s problem was his need to convince the Allies that America could pull her weight in the codebreaking war, and that meant doing a sales job. So he auditioned by cracking a new British cipher destined for the front lines, and won admission to the War Office’s cryptanalytic bureau, where he studied their methods, describing the experience as ‘finishing my education’.

The British wanted Yardley to fly to their GHQ in France to meet the musician-linguist Captain Oswald Hitchings, whose cryptanalytic skills were said by his superiors to be worth four divisions to the British army. Colonel Ralph Van Deman, head of US military intelligence, also then in London, dissuaded him, suggesting that Yardley would have more to learn from the
Bureau de Chiffre
in France. So he went to Paris.

The French Chambre Noire was just as shuttered to Yardley as was Room 40, but his letter of introduction was good enough to get him an audience with Captain Georges Painvin, ‘just recovered from a long and serious illness (the fate of most cryptographers)’. The tall, dark, 32-year-old Painvin cast his black eyes on Yardley without any interest, though Yardley would eventually win him over with his code skills and the two would become lifelong friends.

Painvin, who had graduated near the top of his class from the fabled École Polytechnique, had taught paleontology at the École Nationale Superieure des Mines in Paris, and had won first prize as a cellist at the Nantes Conservatory of Music. He had come to cryptanalysis from the trenches after the Battle of the Marne, and was doubtless certain that this visiting American had nothing to teach him. After all, he had just saved the Allies from astonishing defeat.

Captain Georges Painvin, the French cryptologist who broke Germany’s most difficult code

In March 1918, the war was nearing its fourth anniversary. A generation of young men had been slaughtered, wounded or traumatised, Russia was in revolt, Germany was starving and restive, and her unrestricted submarine warfare had solved nothing. Now that spring was near, with the Americans massing troops in France, the Germans knew that they had to do something huge to win the war before the Americans could make a difference to the Allied cause.

The Allies expected a massive German offensive, but the problem lay in determining from where. Not only did the Germans bring up artillery in stealth; they introduced a new code, one of the most difficult in the history of cryptology. Called the five-letter AFDGX cipher (the V would come later), it was created by Colonel Fritz Nebel and his team of cryptologists, who chose the letters because they sound very different from each other when tapped out in Morse code. And they were certain it was unbreakable.

Nebel’s code used the Polybius square – an ancient Greek invention consisting of a 5 by 5 grid, numbered 1–5 both horizontally and vertically, with each square of the grid filled by a single letter. Nebel’s ingenious twist on this standard of cryptography was to swap out the numbers and replace them with letters. Each German letter was enciphered by two AFDGX letters, so the coded message would be twice as long as the original. The Germans then separated these pairs of letters, and scrambled them according to a key, one that changed every day. The cipher was thus in three parts: substitution, division and transposition.