This book sets out to answer a simple question: how useful is intelligence in war?


01 - Knowledge Of The Enemy: from Napoleon to Al-Qaeda
02 - Chasing Napoleon
03 - Local Knowledge: Stonewall Jackson in the Shenandoah Valley
04 - Wireless Intelligence
05 - Crete: Foreknowledge No Help
06 - Midway: the Complete Intelligence Victory?
07 - Intelligence, One Factor Among Many: the Battle of the Atlantic
08 - Human Intelligence and Secret Weapons
09 - Epilogue: Military Intelligence Since 1945
10 - Conclusion: The Value of Military Intelligence


The literature of fact is exceeded by the literature of fiction. The spy story became, in the 20th century, one of the most popular literary forms and its masters, from John Buchan to John le Carre, grew rich and famous by their writing. The climate created by the masters of spy fiction deeply affected popular attitudes to intelligence work.

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 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.


The golden age of heard communication -- the dot-dash of Morse telegraphy, the human voice of radio transmission -- was comparitively short. It lasted in military terms from about 1850 until the end of the 20th century.

During the Battle of Britain, 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.

In the 45 year struggle between the Germans and the British during the 20th century the Germans unknowingly lost the security of their naval codes early during the First World War and did not regain it.

Gossip helped to refine the picture. Some of the academics who were to accompany the expedition began to boast, a notorious failing of clever men leading unimportant lives.

Even allowing for the tendency of winds to fail or blow in the wrong direction, sailing-ship fleets had an operational autonomy not to be regained by automotive navies until the development of nuclear power.

The Battle of Coronel, 1 November 1914, was the first British naval defeat since the American war of 1812 and the first defeat of a formation of British ships since the Virginia Capes in 1781. News of it appalled the Royal Navy, the British public, the Admiralty, but above all those in high command.


Enigma was to be broken and not long after it had been put into use. Those who achieved the solution were cryptanalysts of the Polish army, which, as the defender of the Versailles state most resented by post-war Germany, took a keen and necessary interest in German military encrypted transmissions. What is extraordinary, positively intellectually heroic, about the Polish effort is that it was done initially by the exercise of pure mathematics.

Crete was a German disaster. It effectively destroyed one of the finest fighting formations in Hitler's army; he resolved never to risk an airborne operation again and largely stuck to his decision. Yet Crete was also a battle that the British lost. Many of those killed, wounded or captured were also soldiers of the highest quality. The navy suffered as badly as the army.

What the events of 20-21 May on Crete reveal is that a defending force, uncertain of how to respond exactly to impending danger, however well informed it may be of the general risk, is at a disadvantage against an enemy who has his aim clearly in mind.


Although Japan had benefitted from the peace settlement of 1919 by its acquisition of the German Pacific islands, it had suffered under the post-war disarmament treaties. The Washington Naval Treaty of 1922, designed to avert another arms race equivalent to that between Britain and Germany widly held to have helped precipitate the First World War, imposed a subordinate naval status on Japan. The US and Britain, arguing that both their navies had two-ocean commitments, in the Atlantic and Pacific, succeeded in bringing their wartime Japanese ally to accept that, as a Pacific power alone, it needed only 60% of their naval strength. This 5:5:3 ratio, as it became known, applied to battleships, cruisers, destroyers and aircraft carriers.
The Japanese, who bitterly resented what they saw as Anglo-American condescension towards their status as a world naval power, had no recourse but to agree. They proceeded, nevertheless, to exploit any loophole in the treaty that was open to them. The Americans and British did likewise.

Since early in the century, the Japanese navy had planned to defeat the American Pacific Fleet by drawing it into Japanese home waters, wearing down its strength meanwhile by attritional attacks as it made its long voyage across the ocean. An early war with the US, however, demanded quicker means of reducing American naval power.

By a combination of interceptions, decoding, informed speculation about Japanese intentions and, crucially, a cunning exercise in the art of the baited signal - the false revelation that Midway was suffering a water shortage - the US Pacific fleet had accurately persuaded itself by May 1942 that the next stage of Japanes expansion would not be westward into the Indian Ocean or southward towards Australia but eastward, from the Japanese home islands, to seize Midway, the last American-held outpost in their proximity.

Between 10.25 on 4 June, when Nagumo was preparing to launch his anti-carrier strike, and 10.30, when Enterprise's Bombing Squadron 6 delivered its attack, Japan's plan to conquer the Pacific was reduced to ruins. Three of its six big carriers had been fatally struck.


The genius of Donitz - he was a sort of evil genius - was to perceive that the submersibility of the U-boat should be used merely to protect it from counter-attack, once its presence was detected, and that in offence it should be used on the surface, where it could achieve speeds superior to most of its targets, the merchantmen, and not greatly inferior to those of all but first-class escorts.
Donitz had argued throughout his life as a professional naval officer that there was a victory waiting to be won between a surface fleet and its submarine enemy. At the end of 1942 he was challened to win such a victory - and lost.

Losses in May 1943 reached an intolerable level, Donitz accordingly ordered a 'temporary shift to areas less endangered by aircraft' by which he meant away from those flown off the escort carriers, from Britain over the Bay of Biscay and from Iceland, Ireland and North America into the former 'air gap' in the mid-Atlantic. It was an admission of defeat, effectively total defeat, for, though new weapons and new U-boat technology would allow sinkings to continue, they would never again approach the level of 1942-early 1943.

What had begun as an unequal struggle between an inadequate fleet of British escort ships, with primitive detection devices and crude underwater weapons, had swelled during the course of the war into a major anti-submarine campaign, prosecuted on the Allied side by an ever-larger armada of British, Canadian and American destroyers, sloops, frigates, corvettes and, critically, escort aircraft carriers, supported by an eventually very large complement of land-based aircraft. In the course of six years of bitter conflict, the Allied had introduced a succession of increasingly efficient detection devices and underwater weapons, including sonar, radar, and a wide variety of depth-charges. In response, the U-boat arm, though greatly expanded in number, from 57 in 1939 to a total of 1153 built by May 1945, scarcely developed at all.


There was little than was romantic about spying in Hitler's Europe. The business was furtive, nail-biting and burdened by the suspicion of betrayal. The German counter-espionage service was extremely efficient at identifying networks, breaking their members and inducing those arrested to inform against their fellow conspirators. Women proved better than men at keeping out of German clutches, because of their superior ability to remain inconspicuous and to deflect difficult questions. Many women nevertheless fell victim to the Gestapo. Their fate, that of women and men alike, was despatch to Hitler's camps.

Bletchley Park's 10,000 initiates kept their secret intact for 28 years.

While the British and Americans were building the Spitfire, Flying Fortress, Lancaster, Mosquito and P51 Mustang, the equal or superior of their German equivalents, and the means by which Germany's cities were flattened during the strategic bombing offensive and the bomber fleets were defended, the Germans were achieving a higher and quite revolutionary level of design and development. Between 1936 and 1944 they built and flew the first practical helicopter (the Focke-Achgelis FW61), the first turbo-jet aircraft (the Heinkel He178), the first cruise missile (the V1) and the first extra-atmospheric rocket (the V2). It was an astonishing achievement, largely conducted in complete secrecy. Only the small size of Germany's industrial base, compared to that of the United States, prevented it from dominating the skies during WW2.

The British realised that by giving details of flying-bomb arrivals correct as to time but wrong as to place - too far north or west - they could cause the Germans to shift the  Mean Point of Impact (MPI) away from London's crowded centre towards its less densely populated suburbs, so diminishing both casualties and destruction. The policy was hotly debated at cabinet level, where allegations of 'playing God' were levelled, but prevailed. It was continued during the V2 rocket offensive and it seems to have had an effect.

It has been suggested that the Peenemunde raid should have been staged earlier, should have been better organised or should have been repeated. Counsels of perfection: not until mid-1943 was the photographic evidence clear enough to identify the site as the centre of the German secret weapons programme. The raid  of 17 August 1943 brought the loss of 40 aircraft, out of 600, an attrition rate of 7%, considerably higher than was deemed 'acceptable' by Bomber Command.

Had Hitler had the vision to devote a proportion of Germany's scientific effort to that given to other weapons programmes to nuclear weapons, it is possible that, with the V-weapons, he could have won the war. The Nazi nuclear research programme was dissipated between too many competing research organisations. There was no von Braun, no Peenemunde and never enough money. The world, nevertheless, had a very narrow escape.


Special forces are a distinctively British contribution to contemporary military capability. They have their origin in Winston Churchill's directive of July 1940 to 'set Europe ablaze', the immediate outcome of which was the creation of the Special Operations Executive (SOE). Churchill's belief, ill-conceived though it proved to be, was that covert attacks by irregular forces within the territory of German-occupied Europe could undermine Britain's enemy from within.

Fertilised by the idea of SOE, the British army's thinking in the middle period of the Second World War turned towards the creation of its own irregular forces, trained and equipped to operate inside enemy territory. The first such units, organised at Churchill's direct order, became the commandos, raiding forces to be landed from the sea; they had their airborne equivalent in the Parachute Regiment.

Churchill, who participated in the Boer War as both a journalist and a soldier, conceived a profound admiration for the Boer spirit. The Boers' dedication to their fight to retain the independence of their tiny republics, and their refusal to submit even when they had been objectively defeated by superior force led him to conclude that the practice of guerrilla warfare, by people of free spirit, could wear down a superior power, fetter its freedom of action, distort its strategy, and eventually force it to make great political concessions not strictly won by military means. He did not place it in context, calculating the likely reaction of a less or more ruthless enemy confronted by a guerrilla action.

Churhcill adopted the Boer term 'commando' to denote the raiding forces he deemed should be raised to attack the flanks of Hitler's Fortress Europe in 1940.

Churhcill was an English gentleman, not only committed to the ideas of fair play and respect for the enemy as an honourable opponent, but believing that such ideas were held by those his country fought. So they had been in the past, when European armied were commanded by other gentlemen.
He imagined that the soldiers of Nazi Germany would refrain from atrocity in the face of resistance as his Tommy comrades-in-arms had refrained in a still unsubdued South Africa. He did not see that raising resistance against a regime imbued with self-righteousness, as Nazism was, would bring down vicious cruelty on those who opposed it.

In the short term resistance, though preserving national honour, brought nothing but suffering to those who raised the standard and to many others who became unwittingly involved in the struggle.
The heroism of SOE's agents should never be diminished. When the balance is struck, however, the objective military value of what they achieved, measured against the consequences of their underpinning what were as much civil as anti-German wars, calls into question the justification for Churchill's desire to 'set Europe ablaze'.

Despite the insertion of numbers of special forces teams into Iraqi territory, no Scud launcher was found and none destroyed. Iraqi ability to hide and protect its weapons of highest value from detection by both external and internal intelligence-gathering means underlay the international crisis that began in 2002.

Saddam Hussein's defiance of the authority of the United Nations, by his refusal to co-operate with its weapons inspectors as required under Resolution 1441 of the Security Council, exemplifies the difficulties of obtaining intelligence about modern weapons systems even under conditions amounting to those of authorised espionage.
The situation was unprecedented. A potential international law-breaker had been obliged to open his borders to officially sponsored investigators of his suspected wrongdoing and yet they remained unable to dispel the uncertainties surrounding his intentions and capabilities. In absolutely optimum conditions, in short, intelligence had failed.

It will be ironic if the literature of the imagination supplies firmer suggestions as to how the war on terrorism should be fought than academic training courses in intelligence technique provide. Ironic but not unlikely. The secret world has always occupied a halfway house between fact and fiction.

The western European states, physically contiguous to countries which hundreds of thousands of young men energetically seek to leave and constrained by their own civil rights legislation from returning illegals to their jurisdiction of origin, even if the facts can be established, are much less well defended than the United States. The security problem by which the Western European states are confronted is not only without precedent in scale or intensity but defies containment.

The 'war on terrorism' may be a misnomer, but it would be foolish to pretend that there is not an historic war between the 'crusaders', as Muslim fundamentalists characterise the countries which descend from the kingdoms of Western Christendom, and the Islamic world. It has taken many forms over more than a thousand years and fortunes in the conflict have ebbed and flowed.

Muslim fundamentalism is profoundly unintellectual; it is, by that token, opposed to everything the West understands by the idea of 'intelligence'. The challenge to the West's intelligence services is to find a way into the fundamentalist mind and to overcome it from within.


"All the Polish codebreaking, all the heartrending efforts and the heroic success, had helped the Polish military not at all. Intelligence can only work through strength."
        - David Kahn, "Seizing The Enigma"

The events of 20-21 May 1941 in Crete demonstrate one of the most important of all truths about the role of intelligence in warfare: that however good the intelligence available before an encounter may appear to be, the outcome, given equality of force, will still be decided by the fight; and, in a fight, determination, again given equality of force, will be the paramount factor.

If asked what spies do, the safest answer is that spies spy on spies.

In the last resort, intelligence warfare is a weak form of attack on the enemy. Knowledge, the conventional wisdom has it, is power; but knowledge can not destroy or deflect or damage or even defy an offensive initiative by an enemy unless the possession of knowledge is also allied to objective force.
Knowledge of what the enemy can do and of what he intends is never enough to ensure security, unless there is also the power and the will to resist and preferably to forestall him.
Western democracies allowed Hitler to undermine their European security system until, almost too late, they took a stand.

Foreknowledge is no protection against disaster. Only force finally counts.


An extract from the first chapter is available to read online at "The New York Times".

John Keegan is the Defence Editor of the Daily Telegraph, and in this Telegraph article he draws on examples and themes from the book to assess the WMD situation in Iraq.

Extracted from an article in Britain's Daily Telegraph entitled "Forget James Bond" :-

Codes, ciphers, spies and secret operations make such gripping stories that their point is usually overlooked. We all know about the Cambridge traitors. What we do not ask is what real damage they did.
The answer is that Burgess did no damage at all, that Philby was harmful only to some unfortunate operatives whom he betrayed to the Russians and that Maclean may have conveyed nuclear secrets to Moscow. Moreover, the Cambridge traitors were figures of the Cold War, not real war.
F H Himsley, the historian of British intelligence in the real war against Hitler, made a sustained attempt to show how intelligence affected its outcome. His conclusion, which did not please the intelligence establishment, is that the efforts of MI6 and Bletchley Park shortened the war, but emphatically did not win it.
His judgment has general application - intelligence never wins wars. As the American David Kahn, the supreme intelligence historian, puts it: "There is an elemental point about intelligence - it is a secondary factor in war."
Intelligence experts hate conceding that truth. The public collude. The reason is that the fiction of intelligence, beginning with Childers and Buchan, reaching its apogee in our age with the works of Ian Fleming and John le Carre, has worked so powerfully on the Western imagination that many of its readers, including presidents and prime ministers, have been brought to believe that intelligence solves everything. It stops wars starting. If they start nevertheless, it assures that the wrong side loses and the right side wins.
If only life were so simple. Any examination of campaigns in which intelligence played a major role reveals a far messier outcome, sometimes exactly the opposite result to the one that might have been expected.
Take, for example, the German airborne assault on Crete in May 1941. Because Bletchley Park was reading the Luftwaffe ciphers, Crete Force knew the date, the time and the exact objective of the German attack.
Nothing, when the attack began on May 21, was a surprise. The British still lost. The explanation is simple. The Germans changed their plan when they realised it was going wrong, while the British stuck to theirs.
The great carrier battle of Midway in June 1942 is another example. The Americans had correctly guessed what the Japanese intended: largely through cipher intelligence, they caught the Japanese at a disadvantage. Nevertheless, five out of their six strikes were shot out of the skies, the last succeeding almost by chance.
In popular belief, intelligence is an arcane commodity, laying bare the innermost secrets of any target against which the intelligence agencies operate. In reality, intelligence is muddled, partial, contradictory, often proving not very secret at all and always confusing. There is a Chinese curse - "May you live in interesting times." A worse curse would be - "May you have to deal with intelligence officers." Poor Prime Minister.
        - from "Forget about James Bond intelligence never wins wars"

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