The Codebreakers: The True Story of the Secret Intelligence Team That Changed the Course of the First World War (36 page)

So too did the Russians call for his release, and on 3 May Trotsky was sent on his way to join the revolution. Later that year, after helping to overthrow the provisional government, and with the Bolsheviks now in power, he became People’s Commissar for Foreign Affairs and began negotiating a separate peace with Germany.

As the Russian will to fight crumbled, both sides on the Western Front were pushed close to breaking point during 1917. Though the Germans stood firm against another series of titanic offensives, the morale of their battle-weary troops began to dip dangerously low. The French army was gripped by a serious mutiny after the cataclysmic failure of yet another onslaught that promised victory but delivered only massive casualties. Order was restored, but the feeling remained that its soldiers could no longer be relied upon. For the British, many months of grinding slaughter lay ahead. By the end of the year, even the Tommies were nearing their wits’ end.

All this misery was accompanied by frenetic technological innovation: anything that might provide even the most marginal tactical advantage was seized upon and hurried into action. The wireless finally came into its own, with the Germans taking the lead. The relative security of the German telephone system could not protect it from the realities of combat: the cables and wires it relied on were extremely vulnerable to the destructive force of artillery, and were constantly severed or mangled beyond use.

Passchendaele, 1917

As a means of battlefield communication, the telephone’s limits were clear. The brave men who ran frantically from one position to another clutching messages were a poor substitute. Seeking a better method, the Germans designed a wireless that could be operated at the front. Known as the ‘trench set’, it was much less cumbersome than the standard wireless sets, which needed a horse and cart to transport them around. The Allies were quick to follow suit with their own version that had a range of 2,000–3,000 yards. Soon the air was buzzing with wireless signals.

Both sides were fully aware that any messages they sent could be intercepted, and set about encoding their wireless comunications. However, if wireless was to make any meaningful tactical contribution to the ebb and flow of combat, transmission and reception had to be as instantaneous as possible. Speed was essential if a message was to have any impact at all. Having to encode then decode the signals inevitably slowed things down. In the heat of battle, and under intense pressure, it’s not surprising that operators made mistakes.

Many found the process extremely frustrating. As the Royal Engineeers’ account of the British Signal service put it, ‘the chief obstacle to the free use of this method of signalling was the stranglehold exercised upon it by the need for … the use of cipher’. A senior wireless officer agreed: ‘ciphers have always been the bugbear of wireless. People don’t like, or they have not the time, to do the enciphering.’

As a consequence, both sides introduced codes that were relatively easy to use. The British relied mostly on the Playfair Cipher. Created in 1854 by Sir Charles Wheatstone, a pioneer of the telegraph, and popularised by his friend Lord Playfair, a fellow scientist with political influence, it substituted one pair of letters for another in the text and used a keyword inserted at the beginning of the message. The German army, which had by now established a codebreaking unit, the
Abhorchdienst
, had no problems deciphering it. Though the British looked for an alternative and tried four different versions of another cipher, none of them was foolproof.

Equally, the Allies were rarely troubled for very long by the German codes. They were contained in two books: the
Befehlstafel
, designed for trench sets and made up of bigrams of common words or expressions; and the regimental-level
Satzbüch
for whole sentences, which eventually included 4,000 mixed-letter code words. To compensate for their simplicity, the German code books were changed with increasing frequency.

At first, a new code book was issued every month, then every 15 days. MI1(b) in London dealt with some of these and managed to crack more than 30 trench codes. According to Tuohy, the ‘toughest code the Germans ever evolved … puzzled our experts for precisely three days and nights back in Cork Street’.

To try and avoid, or at least delay, the inevitable penetration of their codes, both sides tried to confuse their opponents by inserting nonsense into their messages – false or misleading information – as well as dummy groups, a random assortment of material such as quotes from popular songs, poems and proverbs mixed in with irrelevant code book entries. Though these techniques were not sophisticated enough to prevent decryption, they were often too sophisticated for the hapless wireless operators who were supposed to use them. Whether through inexperience, incomprehension or plain incompetence, errors in application persistently undermined efforts to improve cipher security.

The main challenge facing the codebreakers was the sheer volume of messages that had to be processed. In France, the numbers employed by the British for deciphering duties, though small, continued to grow, effectively trebling between 1916 and 1918. The qualities needed were outlined in a memo put together by the intelligence staff. Suitable candidates should possess ‘a lively intelligence … imagination tempered by a highly developed critical faculty’, combined with ‘natural flair’ and ‘untiring patience’.

The reflections of a British officer attached to a codebreaking unit give a picture of the men chosen to work round the clock to unlock the enemy’s messages. There was a schoolmaster, a stockbroker, a solicitor’s clerk and a designer of ladies’ hats – ‘a very rum bird’ – who together occupied a ‘dirty little rabbit hutch’ filled with pipe smoke. They hadn’t a ‘scrap of discipline’, and neglected to wash or shave. When a new code appeared, ‘they pounced upon it like vultures on their prey’ and ‘would wrestle with that new problem until they had made it as clear as day’. If a code was too easy, it angered them; if it was a ‘real hard nut to crack’, they were in seventh heaven. Overall, there was not a single code they were not able to solve within 36 hours.

Perhaps the most talented of these codebreakers was Oswald Thomas Hitchings, who ended the war in command of the Code and Cipher Solution Section at GHQ. Before volunteering in 1914, he was a teacher. A gifted organist, he taught music at two preparatory schools before becoming a modern languages master at Bridlington Grammar School: he learnt French and German via a correspondence course offered by London University. As a musician and linguist, cryptanalysis came naturally to him. However, due to his humble background, at least relative to the social elite poring over intercepts in London, he was attached to the field censor’s office in France. By chance, his commander approached him one day and asked him to take a look at some German messages. He unravelled them with ease. More followed. Hitchings was put in contact with MI1(b) and a steady stream of letters flowed back and forth as he swapped ideas and notes with one of Malcolm Hay’s staff, Duncan Macgregor, a professor at Balliol College, Oxford. Their exchanges bore fruit and Macgregor was sent over to France to assist him. Hay had great respect for Hitchings, and they became firm friends.

The British interception infrastructure grew rapidly during 1917. Wireless observation groups were formed. Each one had around 75 personnel overseeing six interception and two direction-finding stations, dealing with 150–200 messages a week. All the energy and manpower invested in the operation of these new technologies produced a steady stream of knowledge. Its value, however, in terms of delivering materially different results was negligible. The appalling truth about the campaigns of 1917 was that nobody seemed to have learned anything from the horrors of 1916.

During the Third Battle of Ypres, which began in early summer and ended at Passchendaele in November, the British were supposed to break out of the salient and reach the Belgian coast, cutting deep into German-held territory. Within a few weeks, the offensive was hopelessly bogged down, yet Haig persisted in his belief that victory was within his grasp: if not, then at least the Germans were being worn down by the incessant attacks. The trouble was, so were the British.

However much historians argue about the extent to which new tactical thinking was being introduced to break the stalemate, it’s hard to escape the feeling that nothing had changed. The same relentless carnage. The same stubborn adherence to the belief that one more big push would do the trick. The same indifference to the appalling suffering of the troops, sacrificed on the altar of attrition.

Had Haig, at any time from mid August, bothered to actually visit the front lines – if the flimsy, porous, mud-soaked trenches inhabited by the drenched, shivering Tommies, carved into a poisonous bog laced with shell craters filled with fetid water and rotting corpses, can even be called a front line – surely he would have seen that continuing the offensive when any realistic hope of obtaining its targets was gone was not only suicidal but criminal.

The one clear-cut strategic success of 1917 was pulled off by the Germans. Without alerting the Allies, they were able to mount a major withdrawal on the Somme front to a newly prepared defensive bulwark, dubbed the Hindenburg Line by the British, some way back from where fighting had ground to a halt at the end of 1916.

This secret move was achieved through wireless and telephone silence, misdirection, and fake preparations for an offensive at Ypres. Tuohy penned a snapshot account of the moment British interceptors, listening in on the German short-wave trench set, realised they’d been fooled. At around 10 p.m., a ‘bored and jaded NCO’ picked up a signal that indicated that several battalions had retired. Using direction-finding, he then tried to get a better fix on the signal, which showed the German troops were ‘five miles behind where they ought to have been’, leading him to conclude that ‘the whole bloody German army’s gone back’.

What paltry gains the British made during the Somme were now worthless and the Germans were hunkered down in a far superior position. Worse was to come. A year later, they pulled off an even greater feat of deception when they concealed the timing and location of the huge spring offensive that, having taken the Allies by surprise, almost won them the war.

On 4 July 1917, the first contingent of the American army made a triumphal entry into the European war. After a perilous journey across the Atlantic that saw the US navy repel U-boat attacks without losing a single US ship or serviceman, and sinking at least one German submarine, a battalion of the First Army of the American Expeditionary Force survived a rainstorm of flowers and adulation as they marched through the star-spangled streets of Paris, with their commander General John J. Pershing at the helm, to return a martial favour.

‘
Lafayette, nous sommes ici!
’ proclaimed Colonel Charles Stanton, an aide to Pershing and a fluent French speaker, as the Americans paid homage at the tomb of the Marquis de Lafayette, whose French forces had sailed to America in 1781 to help the rebels win their independence from the British.

Though the Americans were welcomed in France with a tumultuous cocktail of hope and relief, their mere presence would not be enough to declare the war an Allied victory: the collapse of Russia had eventually freed up 50 German divisions of battle-hardened Eastern Front troops to head west for one big push towards victory. Despite their muscular ambition, the Americans would not win the war by themselves.

A
New York Times
reporter, one of many covering the American Expeditionary Force’s (AEF) arrival in France, met up with a French drillmaster, who put the task into war-weary perspective, admiring the American troops as the very finest of ‘human beings and raw material’. He issued a caution, however, one born of three and a half years of seeing soldiers march to their doom. ‘But they need a deal of training. The hardest thing to teach them is not to be too brave. They must first learn to hide … Methods in this war are largely those of stealth.’

One of Pershing’s soldiers was largely invisible back in the United States, but he not only became the defining face of the AEF – he and his fellow Choctaw troops would contribute to US military intelligence in a way that neither General Pershing nor Private Otis W. Leader could imagine in July of 1917. Leader had been picked out of General Pershing’s 4 July parade by French artist Raymond de Warreux, who had a commission from his government to paint the ideal US soldier. The artist saw in the handsome 35-year-old Leader ‘a half-blood Choctaw Indian from Oklahoma, straight as an arrow and standing over six feet tall; keen, alert, yet with calmness that betokens strength and his naturally bronzed face reflecting the spirit that they took across with them, the spirit that eventually turned the tide’.

Indeed, the unique contribution of the Choctaws would help the American army begin to turn the tide of battle against the Germans, but Pershing had many other things on his mind that summer. Pershing had come to Europe as commander of the AEF bearing the weight of a great tragedy, as well as great and unusual advancement. In 1913, he had been appointed commander of the 8th Brigade, based at the Presidio military base in San Francisco. The brigade was deployed to Fort Bliss, New Mexico, when the Mexican revolution threatened to boil over into the US. In 1915, Pershing summoned his wife and four children to join him in New Mexico, but on 27 August 1915 he received a telegram that would have destroyed most people: there had been a fire at the Presidio, and his wife and three young daughters were dead. Only his six-year-old son had survived.