CHAPTER ONE
NO WAR can be conducted successfully without early and good intelligence,” wrote the great Duke of Marlborough. George Washington agreed: “The necessity of procuring good intelligence is apparent and need not be further argued.” No sensible soldier or sailor or airman does argue. From the earliest times, military leaders have always sought information of the enemy, his strengths, his weaknesses, his intentions, his dispositions. Alexander the Great, presiding at the Macedonian court as a boy while his father, Philip, was absent on campaign, was remembered by visitors from the lands he would later conquer for his persistence in questioning them about the size of the population of their territory, the productiveness of the soil, the course of the routes and rivers that crossed it, the location of its towns, harbours and strong places, the identity of the important men. The young Alexander was assembling what today would be called economic, regional or strategic intelligence, and the knowledge he accumulated served him well when he began his invasion of the Persian empire, enormous in extent and widely diverse in composition. Alexander triumphed because he brought to his battlefields a ferocious fighting force of tribal warriors personally devoted to the Macedonian monarchy; but he also picked the Persian empire to pieces, attacking at its weak points and exploiting its internal divisions.
The strategy of divide and conquer, usually based on regional intelligence, underlay many of the greatest exploits of empire building. Not all; the Mongols preferred terror, counting on the word of their approach to dissolve resistance. If duplicity enhanced their terrible reputation, so much the better. In 1258, appearing out of the desert, Hulagu promised the Caliph, spiritual leader of Islam, ruler of the Muslim empire, his life if he would surrender Baghdad. As soon as he submitted, he was strangled and the horde moved on. The Mongols, however, as a wide-ranging nomad people, also knew a great deal and, like all nomads, when not on campaign, were always ready to trade. Markets are principal centres for the exchange of information as well as goods, and it was often a demand of marauders—by the Huns of the Romans, frequently by the Vikings—that they should be allowed to set up markets on the borders of settled lands. Commerce was commonly the prelude to predation. Trade may follow the flag, as the Victorians comfortably affirmed, but it was quite as often the other way about.
Empires in the ascendant, to whom nomads were an irritation rather than a threat, adopted a different attitude. They gave and withheld permission to trade and hold markets on their borders as a deliberate means of local control.1 They also pursued active “forward” policies. The pharaohs of the Twelfth Dynasty not only constructed a deep belt of forts on the border between settled Egypt and Nubia but also created a frontier force and issued it with standing orders. Its duty was to prevent Nubian incursions into the Nile Valley but also to patrol into the desert and report. One report, preserved on papyrus at Thebes, reads, “We have found the track of 32 men and 3 donkeys”; nearly 4,000 years old, it might have been written yesterday.
Ancient Egypt’s border problem was perfectly manageable. The narrowness of the Nile Valley, amid the surrounding desert, necessitated the minimum of protective measures. The Roman empire, by contrast, was encircled on all sides by enemies, who might come by sea as well as land, and needed to be defended by elaborate fixed fortifications as well as mobile armies. At the height of their power, Rome’s rulers preferred active to passive defence and maintained strong striking forces at strategic points generally behind rather than on the frontiers. It was only as their power declined and that of the outsiders grew that the border defences were thickened.
Whether on the decline or in the ascendant, Rome devoted great care to the gathering of intelligence. Caesar’s conquest of Gaul was as much the result of his superior use of intelligence as the legions’ superior fighting power. He took great trouble to assemble economic and regional intelligence, just as Alexander had done, and he was a coldly cynical assessor of the Gauls’ ethnic defects, their boastfulness, volatility, unreliability, lack of resilience; he was equally cold in exploiting the advantage his knowledge of their weaknesses afforded. He accumulated a detailed ethnographic knowledge of their tribal characteristics and divisions, which he used ruthlessly to defeat them. Quite apart from this strategic intelligence, however, he also had a highly developed system of tactical intelligence, using short- and medium-range units of scouts to reconnoitre up to thirty kilometres in advance of his main body, to spy out the land and the enemy’s dispositions when he proceeded on campaign. It was an important principle that the leaders of these units had immediate and direct access to his person.
Caesar did not invent the Roman system of intelligence. It was the product of several hundred years of military experience. Evidence for that is already given, by the time of the Gallic wars (first century B.C.), by the existence of established terms for the different categories of reconnaissance troops: procursatores, who performed close reconnaissance immediately ahead of the army; exploratores, longer-range scouts; and speculatores, who spied deeper within enemy territory. The Roman army also made use of local informers (indices), prisoners of war, deserters and kidnapped civilians.2 If not the inventor of the system, Caesar may, nevertheless, be credited with professionalising it and institutionalising some of its most important features, notably the right of direct access by scouts to the commander in person. He also, when necessary, went to see for himself, a dangerous but sometimes essential intervention. Ultimately, the crisis of the empire in the fourth century required the almost continuous presence of one of the emperors (there were latterly two, sometimes more) with the army, a contingency that, at Adrianople in 378, led to his death on the field, progressive disaster and the empire’s collapse. The emperor Valens had been in close touch with his exploratores on the morning of the catastrophe, and they had correctly reported the enemy’s strength and dispositions. What ensued substantiates a profound and enduring truth, that “military and political survival does not depend solely on good intelligence.”3
Systems do not, however, much change, unless circumstances change, and there was little circumstantial change throughout the five centuries of the Roman empire’s greatness (first century B.C.–fourth century A.D.). Reconnaissance throughout the period was by hearing and sight, communication by word of mouth or written despatch, speed of transmission at fastest by that of a fleet-footed horse. What was true of Rome remained true of the world for another 1,500 years.
The collapse of imperial government in the West in the fifth century A.D. entailed also the collapse of organised intelligence services and such ancillary services as the publication of guidebooks and cartography (though Roman maps are strange to us, since they usually took the form of route-charts rather than two-dimensional displays of territorial features, their disappearance was a serious loss to campaigning commanders). Worse by far were the progressive degradation and eventual and complete decay of the road system. The Roman roads were built primarily for the purpose of rapid all-weather military movement and were maintained by the legions, which were as much engineering as fighting units. The dissolution of the Roman army led rapidly to the cessation of engineering work on such key elements of the Roman transport system as bridges and fords. The road network, of course, had not existed during the period of Roman conquest; Caesar had made his way through Gaul by interrogating merchants and locals and impressing guides. It was the roads, however, that had allowed Rome to defend its empire for five centuries and the break-up of their solid surfaces made long-range campaigning at speed impossible.
That was not important to the barbarian rulers who succeeded the Romans, since they sought no more than to maintain local authority. When, however, the attempt began again, under the Carolingian emperors, to reestablish wide imperial domains in the eighth and ninth centuries, the absence of roads was a serious impediment to reconquest. Things got even worse with the attempt to penetrate the Germanic regions which lay beyond the old Roman borders. In those wildernesses there were neither roads nor easily obtainable intelligence.
Some picture of the difficulties confronting medieval campaigners is conveyed by the experience of the Teutonic Knights in their effort to conquer and Christianise the Baltic shore in the fourteenth century. The Teutonic Knights, a crusading order dedicated to the conversion of the Prussians and Lithuanians, were wealthy and highly organised. They operated from a chain of strong castles built on the Baltic coast, in which they were secure from attack and could organise crusading expeditions into the hinterland. One of their principal campaigning grounds was a belt of unsettled land a hundred miles wide between East Prussia and Lithuania proper, a maze of marsh, lakes, small rivers, thickets and forest through which it was almost impossible to find a way. Local scouts were recruited by the Knights to blaze trails and report. Their intelligence was collected in a military guidebook, Die Lithauischen Wegeberichte (The Lithuanian Route Guide), compiled between 1384 and 1402. It explains, for example, that Knights wishing to get to Vandziogala from Samogitia, both near modern Kaunas in Lithuania, a distance of about thirty-five miles by today’s roads, had first to cross a patch of scrub, by a track, then a large wood through which they would have to clear their way, then a heath, then another heath, then a second wood, “the length of a crossbow shot and there you have to clear your way too,” then a third heath and a third wood. Beyond lay the true Wiltnisse (wilderness). A Prussian scout’s letter describing it was copied into theWegeberichte. It reads: “Take notice in your wisdom that by God’s grace Gedutte and his company have got back in safety and have completed everything you sent us to carry out and have marked the way so far as 4H miles this side of the Niemen, along a route that crosses the Niemen and leads straight into the country.” The tone of the report recalls that of the Egyptian border patrol from Nubia 3,000 years earlier; the terrain described is that over which the German Army Group North advanced to Leningrad in 1941, encountering obstacles the Teutonic Knights would have found familiar.4
Curiously, the Holy Land Crusaders faced much less difficulty in getting to Jerusalem in the eleventh century. In 1394, the Grand Master of the Teutonic Knights had answered Duke Philip of Burgundy’s enquiry as to whether there would be a Baltic crusade the following year: “It is impossible to provide a forecast of future contingencies, especially because on our expeditions we are obliged to go across great waters and vast solitudes by dangerous ways . . . on account of which they frequently depend on God’s will and disposition, and also on the weather.” In different words, a modern intelligence officer might respond almost exactly similarly. The Holy Land Crusaders, by contrast, had found a much easier way forward, travelling either by sea or along the surviving Roman roads in Italy or inside the dominions of the Eastern Roman (Byzantine) emperor in southern Europe, where the imperial administration kept communications in repair and furnished supplies. Once arrived at Constantinople, they were provided with guides and escorts and were able to travel on the great Roman military roads that led towards the Taurus Mountains. In what is today eastern Turkey, however, already invaded by Seljuk Turkish migrants from central Asia, they found the roads in disrepair and likewise the other conveniences of travel—cisterns destroyed, wells dry, bridges fallen, villages abandoned. It was a foretaste of how a nomadic, horse-riding people ruined a civilised countryside by rapine and neglect. The final stages of the march to Jerusalem were far harder than the departure from Europe.5
Campaigning inside Western Europe itself throughout the Middle Ages, the leaders of armies found conditions consistently inimical to conducting effective operations. The main problem was a chronic shortage of money in an effectively cashless society, which made the recruitment of armies difficult and their provision with food and supplies often almost impossible. Movement was laborious, because of the absence of an all-weather road system, but the lack of intelligence also impeded the efforts of rulers to deploy such forces as they could raise to the places where they were needed. That difficulty became particularly acute during the crisis of the Viking invasions in the ninth century. The Vikings, who had achieved a revolution in mobility by the development of their superbly fast and seaworthy longships, appeared without warning, overwhelmed local defenders by the ferocity of their assaults and, in the second stage of their terrorisation of the Christian lands, carried violence and pillage deep inland by learning to capture horses in large numbers at their points of debarkation. The antidote to Viking raiding would have been to create navies, but that was beyond medieval kings; another recourse would have been to maintain an intelligence system, to provide early warning, inside Scandinavia. Such sophistication lay even further outside the capabilities of ninth-century kingdoms; moreover, the Viking lands were no place for inquisitive strangers, even with money to loosen tongues. There was much more money to be made by raiding than by selling information, and the Vikings took pleasure in cutting throats.6
By the fourteenth century, the conditions of warfare in post-Roman Europe had altered greatly to the local rulers’ advantage. The overriding need to suppress the aggression of nomadic despoilers—Vikings in the west, Saracens in the south, horse peoples in the east—had stimulated the building of fixed defences, including continuous barriers and chains of castles, which had solidified frontiers, pacified borderlands and restored the possibilities of trade, with beneficial effects on the general prosperity. Kings had money to pay soldiers; they also found the money to buy intelligence and pay agents, who moved with reasonable ease among travelling merchants and, or so at least was suspected by royal governments, under the cloak of international religious orders. It is a mark of how commonplace spying had become during the Hundred Years War between France and England that heralds, the non-partisan arbiters of propriety on the battlefield, went to great lengths to defend their reputation for impartiality; so too did ambassadors, though they were less often believed.
By the middle of the fourteenth century there were extensive networks of English agents in northern France and the Netherlands, usually foreigners working for money, with French counterparts in England, often identified by the royal government as expatriate monks or travelling friars, how accurately is now difficult to establish. What their information was worth is equally mysterious. Even more than would be the case in later ages of improved communications, messages were difficult to transmit quickly in the Middle Ages. The roads were bad, the hire of horses unreliable, the sea a barrier, particularly to the transmission of messages from France to England. The English kings tried to smooth the path. The port of Wissant in northern France, the nearest to Dover, was a usual point of departure, where crossing fees were fixed by law. On the English side of the Channel, post horses were maintained at royal expense for official messages. One piece of evidence suggests that the money was well spent. On Sunday, 15 March 1360, news was brought to the royal council, sitting at Reading, that the French had attacked Winchester, a hundred miles distant, that very day. There is no suggestion, however, that intelligence had brought advance warning.7
Real-time intelligence, except over very short distances, was inherently difficult to acquire in the medieval world. It simply could not be carried quickly enough ahead of the movement of enemy forces. That would remain so for centuries to come. Sometimes critical information did not travel even within the confined space of a battlefield. At Lützen, for example, on 16 November 1632, one of the most important engagements of the Thirty Years War, the Imperial (Austrian) and Swedish armies both made a tactical retreat at the end of the day. The Swedish king, Gustavus Adolphus, had been killed and if Wallenstein, the Imperial commander, had renewed the attack, the Swedes would probably have lost. Neither side, however, was aware of the other’s movements. Next day the Swedes returned, captured the Imperial artillery, which had been abandoned for want of horses to drag it off, and so turned what should have been an Imperial victory into a defeat.8
The European armies of the eighteenth century had become much more professionalised than those of the Thirty Years War. Even so, they found real-time intelligence hard to acquire. Frederick the Great’s campaign of Hohenfriedberg in 1745 was exceptional. The Imperial (Austrian) army was concentrating against him to wrest back the province of Silesia, which the Prussian king had illegally seized in 1740. He got general word of its movement but needed to put himself in a favourable position to resist its attack, by tempting it down into the Silesian plain from the surrounding hills. His first move was to use a double agent he had, an Italian clerk, in Imperial headquarters, to spread the word that the Prussians were retreating. He then concealed his army in broken ground and waited for the Austrians to appear. They made no effort to disguise their movements, and so he was able to make use of rules of observation (indices) which were known to provide rough-and-ready real-time intelligence when the enemy was in view. Dust was an important indicator. “A generalised cloud of dust usually signified that the enemy foragers were about. The same kind of dust, without any sighting of the foraging parties, suggested that the sutlers and baggage were being sent to the rear and that the enemy was about to move. Dense and isolated towers of dust showed that the columns were already on the march.” There were other signs. The gleam of the sun, on a bright day, on swords and bayonets was open to interpretation at distances of up to a mile. Marshal de Saxe, Frederick’s great French contemporary, wrote that “if the rays are perpendicular, it means that the enemy is coming at you; if they are broken and infrequent, he is retreating.”9
Frederick, on 3 June, had positioned himself at a lookout point which commanded the level ground in front of Hohenfriedberg. Towards four o’clock in the afternoon he saw a cloud of dust, through which gradually resolved eight huge Austrian columns advancing towards the Prussian positions, illuminated by bright sunshine. As darkness fell, Frederick ordered a night march. Next morning the Battle of Hohenfriedberg began.
Despite his enjoyment of advantageous intelligence, Frederick did not win an easy victory. His army was outnumbered, and the Austrians and their allies had manoeuvred during the night to outflank him. As so often in war, it was superior fighting power that carried the day; Frederick’s preliminary intelligence success was soon negated. It was his own quick thinking in the heat of action and the fierce reaction of his soldiers which turned the tide of battle.10
The same would most often prove to be true in wars yet to come. In their wars outside Europe, particularly in the North American forests, where Indian allies knew the ground intimately and were masters of the arts of scouting and surprise, European armies were to suffer shocking defeats in the depths of the woods. General Braddock’s disaster at the Monongahela, near modern Pittsburgh, where a large British force was wiped out in a few hours in 1755, was entirely the result of walking blind into an ambush prepared by the French, led by their Native American allies, in uncharted and unscouted woodland. In what both sides came to call “American warfare,” intelligence remained at a premium and usually provided the basis of victory or defeat. In the familiar campaigning grounds of Europe, during the great wars of the French Revolution and Napoleonic empire (1792–1815), intelligence rarely brought victory solely by its own account. That was true even during the British Peninsular War against the French in Spain and Portugal, 1808–14. Intelligence, however good, moved too slowly to bring a real-time advantage. Indeed, Wellington in the Peninsula depended upon exactly the same means of intelligence as Scipio in his campaign against Nova Carthago (New Carthage) in Spain in the third centuryB.C. Wellington, Caesar and Scipio all operated as intelligence-gatherers in exactly the same way. Their earliest concern was to discover the lie of the land (Wellington was a great collector of maps and almanacs) and the characteristics of the enemy. The collection of tactical intelligence—who was where when, what he intended and of what he was capable—was left to the month, the week, the day.11
Wellington had the population on his side, in both Portugal and Spain. France, the invader, was resented, and after the excesses of 1808, hated. Wellington did not have to seek intelligence. It was brought to him by the bucketload. The difficulty was to sort wheat from chaff. Much more illuminating, as an example of intelligence-gathering in the pre-electric age, was the organisation of intelligence during his campaigning days in unconquered India. Wellington (Arthur Wellesley) was in active command of armies in India from 1799 to 1804. Britain, through the East India Company, controlled large enclaves in Bengal, Bombay and Madras but huge areas of the sub-continent were under the rule of local warlords or freebooting hordes. The French, by diplomacy, bribe and direct intervention, sought to bring a majority of anti-British elements to their side. Wellington, operating with small armies of mixed British–Indian composition, was mainly concerned with putting down such independents as Tipu Sultan and Hyder Ali, feudatories of the effete Moghul emperor, who were effectively running their own armies and states.
In order to win, Wellington needed a steady stream of up-to-date information, from both far and near, so as to anticipate the movements of his enemies and gain forewarning of shifts of alliances, the gathering of stores, the recruitment of soldiers and other signs of offensives in the making. The conventional means of securing such a supply of intelligence was to form a reconnaissance corps, of troops either already under command or recruited from the population. The British in India had recourse to another method. They took over a pre-existing intelligence system and made it their own.
The harkara system seems to have been unique to India. Because of the sub-continent’s enormous size, difficult terrain and—until the building of the railways and the trunk roads of the British raj—lack of long-distance routes, power tended to be local. Even when centralised under the Moghul conquerors of the sixteenth century, it remained quite diffuse. The Moghuls in Delhi ruled by devolution, either to mighty provincial officials or by arrangement with local princes, particularly in western and southern India. The system could be made to work only if the court was supplied with regular reports of events at the lesser courts. It came to be supplied by two groups of news-providers: writers, often scholars of high status in the Indian caste system, and runners, who carried verbal or written messages and reports over long distances at high speed.
Over time the system yielded a peculiarly Indian product: the newsletter, usually written in Persian, the language of the Moghul court, in a highly stylised form and on a regular, typically weekly, basis. The letters began as official documents but became, as writers and even runners acquired independence, a sort of private newspaper. Eventually not so private; to whom to distribute the newsletter became a decision of the harkara, who himself acquired a blurred identity, part intelligence-gatherer, part distributor. He also acquired odd rights, to be paid, of course, but also to be accepted as a sort of local correspondent at court, known to be working for other powers at a distant centre.
The harkaras survived because, through their indispensability to those at both ends of the system, they established their independent status. It was an uneasy independence; flogging or even execution could follow the provision of dubious or misleading news. The punishment, however, was personal; it was not intended to undermine the system itself. The system, by the time the British embarked on their progressive supersession of the Moghuls at the end of the eighteenth century, was deeply entrenched in the processes of Indian political and military life. Indian government could not work without it. The British, who were committed to reestablishing Moghul power on an efficient basis, ruling themselves while leaving the Moghuls nominally in charge, simply took it over. They “reconstituted under their [own] control the classic Indian intelligence system which allied the writing skills and knowledge of learned Brahmins with the hard bodies and running skills of tribal and low-caste people.”12
Wellington could not have established himself as the leading sepoy general without the harkaras, whom he both cultivated and tyrannised. His successors continued to do so. Not until the arrival of the telegraph and the establishment of printed newspapers in the middle of the nineteenth century did the harkara system decline; and even so, training in long-distance message-running persisted into the 1920s, sustained by the Indian appetite for news, uncontrolled by official interference, which is such a distinctive feature of sub-continental life. The reason, it has been suggested, why India has become and remains the largest and only real democracy in the Third World is because of its citizens’ insatiable thirst for information.
REAL-TIME INTELLIGENCE: WHAT, HOW, WHERE, WHEN?
Who knows what in sufficient time to make effective use of the news—that is as good a definition of “real-time” intelligence, the gold standard of modern information practice, as is possible—was not often a military consideration in the classical world or even the age of Wellington. Alexander, Caesar and Wellington all operated within the peculiar constraint, to the modern way of thinking, of very slow communication speed over any distance not to be covered by a running man or a galloping horse. The best harkaraswere credited with a speed of a hundred miles in twenty-four hours, but sceptics thought fifty more realistic. The modern marathon, whose runners achieve twenty-six miles in about three hours, gives a better indication of the nature of real-time intelligence before the coming of electricity. The armies and navies of the pre-electricity age operated within an intelligence horizon of considerably less than a hundred miles. Hence the enormous importance attached by the commanders of the past to strategic intelligence: the character of the enemy, the size and capability of his force, its dispositions, the nature of the terrain in his operational area and, more generally, the human and natural resources on which his military organisation depended. It was from guesses based on such factors that generals of the pre-modern world made their plans. Real-time intelligence—where the enemy was yesterday, in which direction his columns were headed, where he might realistically be expected today—was arcane information, rarely to be collected on a real battlefield. As late as 1914, ten divisions of French cavalry, beating the Franco-German-Belgian border for nearly a fortnight, altogether failed to detect the advance of several million German troops. French reconnaissance forces failed again in the same area in 1940. Strategic intelligence is a desirable commodity. It rarely, however, brings advantage in actual time and space. For that, something else is necessary. What exactly is it? How is it possible to assure that the key questions, what, how, where and when, are answered to our advantage, not the enemy’s? That is the theme of this book.
The acquisition of real-time intelligence requires, first of all, that the commander should have access to a means of communication that considerably outstrips in speed that of the enemy’s movement over the ground or water. Until the nineteenth century, the margin of superiority was very small. The marching speed of an army, reckoned at three miles per hour, was exceeded by that of a scout’s horse perhaps six times; but a scout had to make an outward as well as return journey, so the margin was halved. In the interval between scouts making contact with the enemy and returning, moreover, the enemy might advance, reducing the margin still further. Little wonder that surprise was so difficult to achieve in ancient campaigns. When it was, as spectacularly by the Seljuk Turks at Manzikert in 1071, the reason was often treachery or a total failure to reconnoitre, or both. At Manzikert the Byzantine army’s cavalry screen deserted, leaving the commander blind.
Manzikert was an “encounter” battle, with both armies advancing simultaneously. More typical was the situation in which an advancing army ran into the outposts of an army standing on the defence. They automatically raised the alarm and, not having to go out and back, as in encounter operations, but back only, could give early warning. Wellington, for example, during the Waterloo campaign was, though strategically surprised, not so tactically. The French ran into his outposts, allowed him to fight a delaying battle at Quatre Bras on 16 June and to retire to a previously reconnoitred main position at Waterloo two days later.
Surprise was equally as difficult to achieve at sea as it was on land until recent times. Indeed, the traditional problem in naval warfare was for opposing fleets to find each other at all. Hence the tendency for naval battles to occur in narrow waters, or “the shipping lanes,” often in areas where battles had occurred before. In theory, with the invention of the telegraphic flag code at the beginning of the nineteenth century, an admiral, by disposing his ships at the maximum limit of intervisibility—intervals of twelve miles—could, if his chain was long enough, create an early-warning screen which would cover several hundred miles of ocean. In practice admirals never had enough ships; and anyhow, they preferred to keep those they had concentrated, for the danger of being brought to battle dispersed outweighed that of being surprised. An admiral surprised with his ships within range of recall could form a line of battle; an admiral with his ships scattered on reconnaissance beyond quick recall had no such hope. Not until the invention of wireless telegraphy at the beginning of the twentieth century, and its adoption by war fleets, could admirals truly begin to command the far seas. Even then, old habits died hard. Sailors like to see.
Sight is, of course, the principal and most immediate medium of real-time intelligence. It was so in the pre-telegraphic age, and it has become so again in the age of electronic visual display. In the intervening period, which embraces the invention of the electric telegraph in the middle of the nineteenth century and its supersession by radio at the beginning of the twentieth, hearing acquired a superior status. It still enjoys something like parity. Radio in all its forms is an essential tool of military communication. Strategically, it has become less important than the written message electronically communicated, by fax or e-mail. Tactically, it predominates, by immediacy and urgency. In the heat of engagement, voice-to-voice communication between commander and the front line, and in the opposite direction, is what makes battles work, a reality not altered since Caesar took personal, front-line control of the Tenth Legion against the Nervii on the river Sambre in 57 B.C. “Calling to the centurions by name, and shouting encouragement to the rest,” Caesar transformed the tempo of the battle, shifting the psychological advantage to the Roman side and assuring the defeat of the Gauls.
The golden age of heard communication—the dot-dash of Morse telegraphy, the human voice of radio transmission—was comparatively short. It lasted in the military arena from about 1850 until the end of the twentieth century. It was a period punctuated by grave and frustrating blanks, particularly during the First World War, when the intensity of bombardment on the fixed fronts of west and east broke cable communication as soon as mobile operations began, and the signal services had not yet succeeded in acquiring compact radios independent of cumbersome power supplies. Intelligence in real time became an impossibility. Commanders lost voice, indeed any other contact, with their forward troops over the shortest distances, and battles degenerated into directionless turmoil.
Not so at sea. Because of the ready availability of powerful electric current in turbine-propelled warships, radio communication within fleets and between their component units had become standard by 1914. There were difficulties; lack of directionality in contemporary transmitting sets made for interference, so intense in fleet actions that admirals continued to depend upon flag hoists to control their squadrons. Nevertheless, it had become clear by 1918 that the future of naval communications lay with radio.
Not, however, with radio telegraphy (R/T), as voice broadcasts were denoted to differentiate them from wireless telegraphy (W/T) in Morse code. R/T is insecure; the enemy overhearing it is as well informed as the intended recipient. Protection is possible, through very high-frequency (VHF) directional transmission, as in the Talk Between Ships (TBS) system used by anti-submarine escorts to great effect during the Battle of the Atlantic; but it is intrinsically short-range, as a secure means of speech. The only safe way of sending messages over long distance by radio wave is through encryption, effectively a return to W/T. Paradoxically, therefore, the flexibility and immediacy allowed by voice radio was denied both strategically and, except in limited circumstances, tactically, by its insecurity. While the control of naval warfare became, as the twentieth century drew on, increasingly electronic, through the rise of such derivatives of radio as radar, sonar and high-frequency direction-finding (HF/DF), high-level, long-range communication remained stuck at the level of wireless telegraphy, because of the need to encrypt or encode, the resulting message being sent by Morse.
That imposed delay, which was why, though the same imperatives should have applied to army and air force communications, soldiers and airmen, caught up in the dynamics of close-range combat when time was too short to encrypt or encode, broadcast freely by voice radio. Tactical codes were developed—the British army’s Slidex, for example—but even Slidex took time. In the cockpit of a single-seat fighter, any form of encryption was impossible. All armies and air forces therefore set up tactical overhearing services, called “Y” by the British, which listened in to the tactical voice radio transmissions of their opponents.13 Y frequently supplied battlefield intelligence of high value. During the Battle of Britain, for example, the British intercept stations were able to anticipate the warning of air raids supplied by the Home Chain radar stations by overhearing the chatter of Luftwaffe aircrew forming up before take-off on their French airfields.
Y was nevertheless of limited and local military value. Important radio communications were, from the First World War onwards, always encrypted or encoded, and only a combatant equipped to render secret writing into plain text could hope to do battle on equal terms with the enemy. The competence of the major powers varied, between themselves and also over time. In the forty-five-year struggle between the Germans and the British during the twentieth century, for example, the Germans unknowingly lost the security of their naval codes early during the First World War and did not regain it. The British, partly by capture and partly by intellectual effort, were able to reconstruct their enemy’s book codes in 1914 and thereafter to read high-level German communications at will. In the aftermath of the war, hubris—a repetitive influence on secret communication—led the British to believe their own book codes impenetrable, while the Germans during the 1930s both broke the British book codes, an intrinsically insecure means of secret writing, and adopted a machine cipher system, Enigma, which would resist the attack of its enemies’ cryptanalysts—Polish, French and British—until well into the course of the Second World War. The Polish success in breaking Enigma before 1939 was negated before the outbreak of war by German variation of their machine encryption.
There are other means of acquiring intelligence in real time besides seeing and hearing, notably through the indirect sight provided by photographic intelligence and, today, satellite surveillance; human intelligence—humint, or spying—can, in certain circumstances, also convey critically urgent information. Both, however, are prone to delay and defect. Images, however acquired, need interpretation; they are often ambiguous and can cause experts to disagree. Thus, for example, photographic evidence brought back to Britain from the German pilotless weapons development station at Peenemünde during 1943 did show both the V-2 rocket and the V-1 flying bomb. The weapons went unrecognised for some time, however, in the first case because the interpretation officers did not recognise the rocket in its upright, launching position, in the second because the image of the V-1 was so small—less than two millimetres across—that it was missed. Yet the pilotless weapon photographic evidence was comparatively clear and was supported by other intelligence which told the interpreters what it was that they should be seeking to identify. They knew they were looking for “rockets” and miniature aircraft; even so they failed to recognise the evidence before their own eyes. How much more difficult is image interpretation when the interpreters do not know exactly what the evidence will resemble when they see it: the hideouts of al-Qaeda terrorists, the bunkers of illegal Iraqi weapon development centres. The intelligence of imagery is frustratingly rich—many needles but in a vast haystack.
Human intelligence may suffer from different limitations: including, first, practical difficulty in communicating with base at effective speed; and, second, inability to convince base of the importance of the information sent. The world of human intelligence is so wrapped about with myth that any clear judgement about its usefulness is difficult to establish. It does seem, that, for example, the Israeli foreign intelligence service was running an “agent in place” at a high level in Egypt before that country’s attack on Israel in 1973. Because the Egyptian government dithered over the decision to attack, the agent sent a succession of self-cancelling reports, with the result that, when the attack came, the Israeli army had gone off high alert. True or not, the story leaves unresolved the question of how the agent was able to communicate in real time. The case of Richard Sorge was entirely different; he was both highly placed and well equipped to communicate by clandestine radio. His difficulty—of which he was unaware—was to secure a hearing. Sorge, a committed Communist and long-term Comintern agent, had established himself before the Second World War in Tokyo as the respected correspondent of a German newspaper. As a German native and citizen thought to be entirely patriotic, he became intimate with the staff of the German embassy, passed on information about Japanese affairs the diplomats found useful and eventually began to assist the ambassador in drafting his reports to Berlin. As a result, he was able to send the assurance to Moscow, during the terrible summer of 1941, that Japan did not intend to assist its German ally by attacking the Soviet Union through Siberia. He had earlier sent convincing warning of Germany’s intention to invade and had even identified the correct date, 22 June. Stalin had received other warnings, including one from Churchill, but chose to ignore them, as he ignored that of Sorge. The idea of war was too uncomfortable; Stalin preferred to believe that he could buy Germany off by fulfilling delivery of strategic materials, including oil. As to the assurance that Japan would not invade Siberia, the evidence is that Stalin had moved a large portion of the Soviet garrison out of Siberia before the attack of 22 June and that Sorge’s warning, even if heeded, was not the critical strategic intelligence it seemed to be.14
Other celebrated human intelligence organisations of the Second World War, the “Red Orchestra” in Germany and the “Lucy Ring” in Switzerland, also lack credibility as media of real-time intelligence, though for different reasons. Sorge is almost unique among identified operators in the world of humint by reason of his undoubted access to information of high quality and his ability to forward it speedily to base. The Red Orchestra, a coterie of left-inclined Germans of superior social standing, was a dilettante organisation led by a Luftwaffe officer with a double-barrelled name, who seems to have been animated by the excitement of misbehaviour. They transmitted little of importance to Moscow, betrayed themselves by lack of elementary security precautions and were rapidly rolled up by the Gestapo. The information supplied by the Lucy Ring—in reality an individual called Rudolf Roessler—to Moscow from Switzerland during the war seems to have been derived largely from his study of the German press. The rest was fed to him by the Swiss, who maintained contacts with the German Abwehr. The Swiss feared that a German victory would lead to the incorporation of their country into a greater Reich; the Abwehr was adept at playing a double, if impenetrable, game. Roessler may have belonged to that colourful gang of fantasists who enriched themselves, at the expense of the secret service budgets of many countries, throughout the Second World War.15 In any case, he lacked a radio link to Moscow.
The ability to communicate, quickly and securely, is at the heart of real-time intelligence practice. It is rarely enjoyed by the agent, that man of mystery who figures so centrally in the fictional literature of espionage. Real agents are at their most vulnerable when they attempt—by dead letter box, microdot insertions in seemingly innocent correspondence, meetings with couriers, most of all by radio transmitter—to reach their spymasters. The biographies of real agents are ultimately almost always a story of betrayal by communication failure. A high proportion of the Special Operation Executive (SOE) agents in France during the Second World War were discovered by German radio counter-intelligence; the same was true of those operating in Belgium while, as has become well known, at one stage all agents dropped into Holland were collected on site by German manipulators of the SOE radio network. Even when counter-intelligence is deplorably lax, as in the notorious “Missing Diplomats” case, the certainty of Donald Maclean’s guilt was finally established, even if retrospectively, by his habit of leaving Washington to meet his Soviet controller in New York twice a week.16
It is the intrinsic difficulty of communication, even, indeed above all, for the agent with “access,” which limits his—or occasionally her—usefulness in real time. By contrast, the enemy’s own encrypted communications, if they can quickly be broken, will, of their nature, provide intelligence of high quality in real time.
The history of “how, what, where, when” in military intelligence is therefore largely one of signal intelligence. Not exclusively; human intelligence has played its part, and so, latterly, have photographic and surveillance intelligence. In principle, however, it is the unsuspected overhearing of the enemy’s own signals which have revealed his intentions and capabilities to his opponent and so allowed countermeasures to be taken in time.
The case studies that follow will support this argument. Not, however, in its entirety; one case study, that of the German airborne descent on Crete in May 1941, has deliberately been chosen to demonstrate that even the best intelligence will not avail if the defence is too weak to profit by it. Other studies—particularly those of the Battle of the Atlantic and the V-weapons—emphasise the parallel importance of non-intelligence factors, in the first case, and of photographic intelligence and humint, in the second, in defeating the threat. The book begins with studies of intelligence campaigns in the age before signal intelligence was available to a keen-eared listener. The examples of Nelson’s Mediterranean campaign of 1798 and Stonewall Jackson’s campaign in the Shenandoah Valley in 1862 may persuade those who expect too much—or too little—of modern intelligence-gatherers and -users to reconsider their opinions.
It has become part of the conventional wisdom that intelligence is the necessary key to success in military operations. A wise opinion would be that intelligence, while generally necessary, is not a sufficient means to victory. Decision in war is always the result of a fight, and in combat willpower always counts for more than foreknowledge. Let those who disagree show otherwise.