Intelligence in War: Knowledge of the Enemy from Napoleon to Al-Qaeda

by John Keegan

In fiction, the spy is a glamorous figure whose secrets make or break peace, but, historically, has intelligence really been a vital step to military victories? In this breakthrough study, the preeminent war historian John Keegan goes to the heart of a series of important conflicts to develop a powerful argument about military intelligence.

In his characteristically wry and perceptive prose, Keegan offers us nothing short of a new history of war through the prism of intelligence. He brings to life the split-second decisions that went into waging war before the benefit of aerial surveillance and electronic communications. The English admiral Horatio Nelson was hot on the heels of Napoleon’s fleet in the Mediterranean and never knew it, while Stonewall Jackson was able to compensate for the Confederacy’s disadvantage in firearms and manpower with detailed maps of the Appalachians. In the past century, espionage and decryption have changed the face of the Japanese surprise attack at the Battle of the Midway was thwarted by an early warning. Timely information, however, is only the beginning of the surprising and disturbing aspects of decisions that are made in war, where brute force is often more critical.

Intelligence in War is a thought-provoking work that ranks among John Keegan’s finest achievements.

Genres: History, Military Fiction, Nonfiction, Military History, War, Espionage, Politics

387 pages, Hardcover

First published January 1, 2003

About the author

Sir John Desmond Patrick Keegan, OBE, FRSL was a British military historian, lecturer and journalist. He published many works on the nature of combat between the 14th and 21st centuries concerning land, air, maritime and intelligence warfare as well as the psychology of battle.

Reviews

[Phrodrick slowed his growing backlog · Rating 2 out of 5]

For decades Professor John Keegan has been one of my favorite military go to historians. I could easily be one of his squealing fainting fans. With sadness I must report that Intelligence in War is not up to his standard and cannot be recommended. His case study methodology, elsewhere very illuminating; fails to fully serve this topic. At least some level of quantitative research would have helped to save this book.

The first warnings are in the introduction when he admits that he is not well trained in the very large field of Military Intelligence. Not in itself a fatal limitation, but nothing that follows indicated that he overcame his limitation. Next he notes that in any number of fictional examples of espionage and spy books, the success or failure by the agents do not end the war or save the planet or whatever his criteria. Never mind that fictional spies save the world so often that the trope itself has become a joke. Fictional spies are always saving the world. For the more realistic examples of fictional espionage work blaming the spy for not changing history is like blaming a rifle company for failing to end an entire war.

The example of the rifle company is deliberate. It is unrealistic to expect intelligence alone to be author of victory. Who has what soldiers where, after the battles are fought that most determines who has won the war. Everything else is more or less important, and by implication more or less incidental.

The research question: What are the limitations of wartime intelligence? is valid. The professor’s examination of the question is insufficient.

Military Intelligence in its broadest definition can so inform the possessing nation that policy level decisions favor peace or war. This is what the U2 flights over Cuba achieved over Cuba. Their refusal to believe intelligence lead the Japanese to launch a war against the western nations and the US. How many wars have been avoided or launched based on pre-war intelligence assessments is a question never properly researched by John Keegan.

If the above examples are accepted as absolute fact, there is no reason to believe that the outcomes of each example had to be: a peaceful resolution of Soviet Russia’s attempt to place nuclear missiles minutes away from the US; or the stunning surprise attack on a vulnerable Pearl Harbor.

It is just as valid to argue that it was the limitations on Japans relative economic and industrial capacity that most directly resulted in Japan’s ultimate defeat. Do we now need a new case study called the Supplies in War, to document the value and limitations of supplies? Can we make a similar case for moral, or religion or paymasters or head gear? The point is that intelligence is an input. It is a tool. It is a part of a larger set of facts. A good general makes do with what is available at the time of battle. The same good general will have seen to it that his subordinates, including those with little or no access to the full intelligence briefing are best picked and placed to make the best decisions, given what they know at decision making time.

Battle, can be conceived of as the sum of numerous smaller engagements. The relative will, training, equipage, and a inventory of tangibles and intangibles may be the immediate predictor of individual or collective outcomes. What most good generald understand is the relative importance of Luck. (Attributed to many including Gen. Eisenhower: ‘I would rather a lucky general than a smart general”).

What the best generals do is to work to improve or make their own luck. One, and only one of the tools for making luck is good, accurate, properly analyzed intelligence.

It is telling that Keegan recognizes both the value of luck and quality soldiering but never quotes the best of the strategists on these topics.

It is a major failing of the book that his book is uninformed by Sun Tzu. Even a few quotes would prove that he had made the effort to use research to augment his lack of depth on this subject.

Attributed to or directly quoted from Sun Tzu:

If you know the enemy and know yourself you need not fear the results of a hundred battles.
Thus, what enables the wise sovereign and the good general to strike and conquer, and achieve things beyond the reach of ordinary men, is FOREKNOWLEDGE.

Hence the use of spies, of whom there are five classes: (1) Local spies; (2) inward spies; (3) converted spies; (4) doomed spies; (5) surviving spies.

When these five kinds of spy are all at work, none can discover the secret system. This is called "divine manipulation of the threads." It is the sovereign's most precious faculty.

[Kuszma · Rating 4 out of 5]

1.
„Igazából, ha valaki megkérdezi, mit is csinálnak a kémek, a legbiztosabb válasz így hangzik: egymásra kémkednek.”

A legtöbben a felderítés szó hallatán bizonyára a kémekre asszociálnak, előírásszerű ballonkabátban és napszemüvegben, amint épp egy atomkutató intézet kapuját figyelik egy fa mögül. Nyilván mert komplett zsáner épült fel arra (olyan pazar szerzőkkel, mint Le Carré), hogy a hírszerzésnek ezt az oldalát domborítsák ki. Ám a kémek (Keegan szerint) csak olyan, gyakran gyenge erkölcsű pacákok, akik elbíbelődnek más államok kémeinek vegzálásával, esetleg felforgatnak* egy kicsit valami eleve instabil államban, de valójában nem különösebben befolyásolják a háborúk menetét**. Csak egy egészen pici szeletét képezik annak, amit hadászati felderítésnek nevezünk – és amibe beletartozik a térképészettől a rádiós lehallgatáson át a rejtjelfejtésig egy csomó minden. Keegan ennek az izgalmas témakörnek a bemutatását tűzi ki célul. Szövegének gerincét hét tanulmány alkotja, amelyekben Nelson és Napoleon Földközi-tengeri csörtéjétől kiindulva eljut a V-1-es és V-2-es rakéták utáni hírszerzési hajszáig***. Ezek az írások önmagukban is komplett alkotások, igazi csemegét jelentenek azoknak is, akik csak úgy általában érdeklődnek a hadtudomány iránt – együtt pedig kirajzolódik belőlük a felderítés evolúciója, a technikai eszközök és a katonai gondolkodás folyamatos fejlődése. És akkor még nem is említettem a remek keretet, amely segítségével a szerző elhelyezi az egész miskulanciát egy általános kontextusban.

2.
„A háború nem intellektuális, hanem brutálisan fizikai természetű jelenség. A háború mindig a felőrléses küzdelem felé tendál, ami lényegében versengés a vérveszteségek okozásában és elviselésében, és minél jobban megközelíti a felőrléses küzdelem a lehetőségek határait, annál kevésbé számít a gondolat.”

(Kapcsolódó idézet Thomas Troubridge szájából, aki Nelson egyik hajóparancsnoka volt: „Valahányszor azt látom, egy fickó úgy néz ki, mintha gondolkodna, én azt mondom: íme a zendülés!”)

Szóval érdekes dolog ez a felderítés, de Keegan hangsúlyozza, hogy jelentőségét nem szabad túlbecsülni. Alapvető igazság, hogy hiába tudunk mindent az ellenségről, a győzelem attól függ, hogy kellő erőt tudunk-e a csatamezőre összpontosítani. Vannak ugyan sikertörténetek – az Enigma kódjának feltörése például alighanem évekkel megrövidítette a második világháborút. De hiába adott ez a siker a Krétát védő angol csapatok kezébe szinte minden lényeges információt, a csatamező konkrét közegében elkövetett súlyos hibák megfosztották a szövetségeseket egy biztosnak tűnő győzelemtől. Vagy itt van a Midway-szigeteki csata, ahol az amerikaiak minden lényeges információt kiolvastak a japán hadihajók rádiójeleiből – de lehengerlő győzelmük mégis egy fatális véletlennek és a japán parancsnok gondatlanságának volt köszönhető. Szóval szép dolog a felderítés, valóban szép, ám alighanem az a legszebb, ha sokkal több és jobb anyahajód van, mint a másiknak.

Szokásos lendület és meggyőző erő, Keegant most is öröm volt olvasni.

* Lásd a felforgatók gyöngyét, James Bondot, akiről – csak mert jól áll neki az öltöny – hajlamosak vagyunk elfelejteni, hogy valójában egy állami bérgyilkos.
** Vannak néha kivételek, de általában róluk is kiderül, hogy valójában nem tettek hozzá sokat a küzdelem végkimeneteléhez. Itt van például a szovjet ügynök, Sorge, aki ugyan mindent megtudott a nácikról, ami megtudható volt, de hiába szállította a pontosabbnál pontosabb adatokat Sztálinnak, az lesöpörte azokat az asztalról.
*** Az epilógusban pedig egyéb csemegék is akadnak, például a Falkland-háború, az Öböl-háború vagy a szeptember 11-et követő terrorizmus elleni harc.

[Don Yurmanovich · Rating 4 out of 5]

I'm not going to pretend like this will be an unbiased review. I am a huge Keegan fan and have read five of his other books. Keegan's method, one of which I am particularly fond, attempts to give the reader a broader understanding of military history. This is not done by sketching an overall connective and encompassing outline but instead by taking a few slices from different eras and showing how they fit into the larger history. Both the small and large scale are needed to interpret and comprehend the other fully. In this work, he starts with Nelson in 1798 and essentially ends with the Falklands War. He touches on Al-Qaeda but not much history is given.

As I have come to expect from him, Keegan writes with both clarity and density in 'Intelligence in War'. I had to resist the urge to highlight entire pages. Even for the events of which I was knowledgeable, he added detail and analysis that was enlightening. I read a book entirely on the Falklands War and yet his partial chapter on it added details I didn’t know. With all this being said, let me add some reflections on the book.

1) The book is heavy on the naval side. This isn't necessarily a bad thing; I find naval warfare fascinating. But I do wonder if it skews the analysis. Perhaps it would be worth splitting it into two volumes: one for naval and the other for land operations. I will return to the scope of the book later. But as it stands, there are chapters on The Mediterranean Campaign of 1798, von Spee's East Asia Squadron, The Battle of Midway, The Battle of the Atlantic, and a portion of the last chapter on The Falklands War. Land campaigns covered are only Shenandoah Valley and Crete. The hunt for the V1/V2 programs doesn't fit into either category neatly. Maybe it could be considered an air campaign.

2) It is also heavy on the modern side; four of the chapters are from WWII. His other books tend to have a better balance from different eras. Part of his point seems to be that useful intelligence was almost non-existent before electronic means of transmitting data. Maybe he is correct here, particularly from a strategic viewpoint, but this leads to my next point:

3) His definition of military intelligence seems rather narrow. I think the book does a good job of creating skepticism towards what might be a mythologized form of military intelligence: a key piece of information is discovered and a general alters his battle order last minute to seize victory. And to be fair, he does specify that he is only referring to operational intelligence. But why not speak of intelligence more broadly? I wonder if Keegan’s theme is aimed at an attitude much more prevalent in the UK than the US. After all, the "WWII was won with American steel, British intelligence, and Russian blood" is still repeated ad nauseam today. Perhaps in Britain the idea of intelligence equaling victory is popular. Otherwise, I wonder who holds the view he argues against. I have heard that human intelligence needed/needs to be rediscovered in the war on terror but he agrees that, in this case, good intelligence will be invaluable. And hence, point 4.

4) While the war of terror has a larger scope, it is not fundamentally different from a whole host of wars throughout history. By acting like the GWOT introduces some new scenario where intelligence is of utmost importance ignores the entire history of small wars, insurgencies, and guerilla strategies. He even mentions in passing that these types of wars in the second half of the 20th century involved more of the world’s population than World War II. Keegan seems to completely sideline half of military history, which is most notable because it is precisely the type of conflict in which intelligence is a primary asset. This omission, in my opinion, weakens the book far more than the other issues previously mentioned.

Keegan’s book offers a great deal of knowledge on battles or operations unknown to many readers. He writes with lucidity and depth about the slices of history he highlights and I would recommend the book to anyone interested in military history. However, unlike many of his other books, I do not feel that these slices are a good representation of the overall picture and I am not convinced of his overarching thesis. Actually, I should be more specific. I’m unclear about exactly how far he wants to push his thesis. Does intelligence alone win wars? Of course not, but no one is arguing that as far as I can see. So how useful is military intelligence? Not very, seems to be Keegan’s answer. But I think his scope is strangely still too limited and the framing too restrictive for a satisfying answer.

Final note: this was written in 2002, so be prepared for some remarks on Iraq that have aged, let’s say, quite poorly

[Alberto Illán Oviedo · Rating 5 out of 5]

Ensayo muy ilustrativo de lo que es y supone la inteligencia militar, alejándolo del romanticismo que se ha creado en torno a novelas, películas y series que suelen ser las principales fuentes de conocimiento para los aficionados. Tras un primer capítulo en el que nos define los conceptos básicos, nos zambullimos en varios hechos históricos que describe y analiza desde el punto de vista de la inteligencia, observando cómo ésta no siempre es determinante e importante en la resolución del conflicto, incluso cuando se tiene toda la información en el momento adecuado. El último capítulo, dedicado a las conclusiones, es quizá el más aclarador. Una lectura muy recomendable.

[Lee · Rating 3 out of 5]

This book has a lot to recommend it. It is a series of case studies focusing on the usefulness of intelligence in specific battles. Keegan's thesis rejects the normal understanding of intelligence, that "knowledge is power." Instead, Keegan convincingly suggests that intelligence is usually peripheral to determining the outcome of a battle. Power, and the willingness to exercise it through brute, physical force, is the most important point to determining the outcome of a battle.

He proves this by looking at specific battles, largely focused on World War II, the Battle of Crete, the Battle of Midway and the Battle of the Atlantic. Tacked onto these are Stonewall Jackson's Valley Campaign and Nelson's search for Napoleon's fleet. In each of these, he shows the role that intelligence played in the battle. In the Battle of Crete, though the British forces had perfect intelligence, they still were defeated by the German force's brute force.

Another point that he implies is that intelligence did not really exist in the form that we think of it today until fairly recently. This largely comes down to communication technology. Before radio, it was difficult to get enough useful intelligence to intelligence consumers to be effective. Stonewall was able to use his knowledge of the Shenandoah Valley, particularly that gathered through his cartographer, but this is not really the work of the modern spy. His cursory review of intelligence from before Napoleon demonstrates how unimportant it was.

I have two criticisms of this work. The minor one is that, it is hard to follow some of the battle sequences, particularly as I was listening to it on an audiobook. The Stonewall and Nelson chapters are particularly hard to grasp without a map.

The larger criticism of Keegan's work is his belief that anyone who is not white is far too incomprehensible for the Western mind to comprehend. When talking about the Japanese, he occassionally slips into an Orientalism that seems like something pulled from a book in 1903, not 2003. On one occassion, in his analysis of the Japanese, he says they slip into the traditional complexity of the Oriental mind. Obviously this is wrong and a failure to try to understand the Japanese, but it also makes for a slipshod analysis.

This orientalism bleeds into his analysis of Al Qaeda. He complains that these groups are ununderstandable to the Western mind, something that is clearly misguided. The final section on Al Qaeda seems like it was shoehorned in to make the book seem relevant after he had already been writing the book for years. The book would be stronger if Keegan had jettisoned the analysis of groups he decides he cannot understand rather than whining about how incomprehensible they are.

[Scott Neal Reilly · Rating 2 out of 5]

This is a history of the use of intelligence of a variety of types in war. The main thesis is that human intelligence (spying, espionage, etc.) is usually associated with intelligence but that the most important forms of intelligence are actually based on electronic surveillance and code decryption. This is a fine and interesting point. The presentation, however, tends to focus less on intelligence and more on warfare and the narratives of particular battles where intelligence played some role, but the role of intelligence is often minimal. For instance, an entire chapter is devoted to Nelson chasing Napoleon around the Mediterranean because he didn't know where Napoleon's ships were as there was no way to gather such information at that time. Using this to make a point is fine, but the chapter went into great depth about what is a relatively uninteresting example from an intelligence standpoint. On the other end of the title is the role of intelligence in the battle against Al Qaeda, which seems like it should provide a wealth of positive examples. I guess this was a naive hope on my part (though one that was based largely on the title of the book) as much of that information must necessarily be classified, but the entire discussion takes up a brief reference in the Afterward. The book is mostly well written (a few places where it could use some improved editing, but nothing major) and probably interesting to those who enjoy warfare narratives, but it was disappointing from the standpoint of wanting to understand intelligence and intelligence gathering better.

[Preetam Chatterjee · Rating 3 out of 5]

I bought Intelligence in War on Amazon with the idea that I’d dip in and out — you know, browse a few battles, marvel at a codebreak here or there. But Keegan doesn’t let you skim. He grabs you by the collar and throws you onto battlefields from Napoleon’s Europe to bin Laden’s Afghanistan, asking over and over: what did the generals know, and when did they know it? This isn't just a book about spies and signals — it's a meditation on the limits of knowledge when bullets start flying.

Keegan takes us through the fog of war — Nelson at Trafalgar, Stonewall Jackson’s eerie brilliance, the agony of Midway, the brutal genius of Soviet deception — and in every chapter, he quietly destroys the myth that intelligence alone wins wars. It's not what you know, he says. It’s how you act on what little you do. As I read, I found myself scribbling marginalia like a mad strategist, wondering what would happen if this principle was applied to politics… or parenting… or teaching English.

And somewhere between the Enigma machine and aerial surveillance over Kosovo, it hit me: Keegan is warning us. About overconfidence. About assuming information equals control. Reading it during a late-night thunderstorm, the rain hitting my window like Morse code, I felt like history was whispering across centuries: Clarity is rare. Act anyway.

[Mike Harbert · Rating 3 out of 5]

Like most of John Keegan's books, this is not necessarily an easy read. Keegan's prose is often difficult for American readers, but I find that after about 100 pages it gets easier.

This book is not intended to be a comprehensive history of the application of intelligence in modern warfare. Instead, much like Keegan's much better "Mask of Command," he provides a series of vignettes detailing some of the greatest moments in the use and application of military intelligence, loosely tied together in a larger theme.

Overall, I am generally a fan of John Keegan. I thought that "Mask of Command" and "Face of Battle" were excellent, well researched, well written, and insightful. They clearly show Keegan's brilliance as a military historian. "Intelligence in War" falls far short of that standard. In my mind, the book seems rushed, cursory, and rather lacking Keegan's usual insight.

I guess that it could serve as a decent survey of the evolution of military intelligence in modern war, but it is clearly not Keegan's best work. Personally, I was disappointed.

[Tony · Rating 2 out of 5]

This one needed some gravy. The subject matter is infinitely interesting, but the delivery here was too analytical and academically-dry for me to really enjoy the stories behind the history. I have loved reading John Keegan, before, but this one didn't hold me like his others.

[Ellie Márquez Romero · Rating 5 out of 5]

La guerra no es un ejercicio intelectual, sino una actividad brutalmente física en la que ambas partes se empeñan en desgastar al enemigo.Es decir, una confrontación en la que se provoca, y se soporta, el derramamiento de sangre; y mientras más intenso es el desgaste menos cuenta el pensamiento. Todos desean el triunfo al menor coste posible. El pensamiento ofrece vías para reducir el coste: se pueden identificar las debilidades del enemigo en su método de guerra o su sistema defensivo.

La totalidad de los casos estudiados en este libro se refieren a la inteligencia militar en su sentido más estricto, a saber: cómo el empleo de la inteligencia logró conducir al enemigo al combate en las condiciones más propicias para el vencedor.

El objetivo de este libro es demostrar que por muy buena que sea la inteligencia, no siempre conduce a la victoria, y que en última instancia lo que cuenta es la fuerza y no el fraude o la previsión. Pero esta opinión no está de moda. Constantemente se nos dice que la superioridad de la inteligencia es la clave del éxito en la guerra, particularmente en la guerra contra el terrorismo. Es indiscutible que pretender hacer una guerra sin la orientación que puede proporcionar la inteligencia equivale a dar palos de ciego, a errar, a lanzar golpes que no llegan al objetivo o que ni siquiera se le acercan. Todo esto es cierto: sin la inteligencia los ejércitos y las armadas sencillamente no se encontrarían, por lo menos no en el corto plazo, tal como solía ocurrir antes de existir la electricidad; y si se encontraran, probablemente la fuerza mejor informada llevaría las de ganar.

No obstante , admitida la importancia de la inteligencia para la previsión, es preciso reconocer que si los enemigos realmente desean El enfrentamiento, siempre hallarán la manera de encontrarse, y cuando esto suceds, rara vez los elementos de la inteligencia serán determinantes en el resultado. En general, la inteligencia es necesaria pero no basta para garantizar la victoria.

Son dos las razones por las que en la actualidad se sobreestima la importancia de la inteligencia en la guerra: la primera es que suelen confundirse con el espionaje y el contraespionaje con la inteligencia operativa propiamente dicha;la segunda esla interrelación de l inteligencia operativa con la subversión, y su contaminación por este método de obtención de ventaja militar por medios encubiertos.

Finalmente, también la inteligencia es una modalidad frágil de ataque al enemigo. Suele decirse que en la información radica la fuerza, pero la información por si sola no puede destruir, prevenir, dañar, ni siquiera desafiar una ofensiva del enemigo, a menos que la posesión de la información esté acompañada de la fuerza objetiva.

[Tony · Rating 4 out of 5]

John Keegan is a fantastic writer with INTELLIGENCE IN WAR as another great contribution to military history. This book is accessible to the average interested reader as well though. Keegan narrates nearly a dozen case studies and then the intelligence takeaways from them. The ultimate conclusion of his book is two-fold.

First, "intelligence" does not win wars, the successful application of brute force does. However, intelligence can often make that task easier.

Second, since Winston Churchill's command to "Set Europe ablaze!" during World War II, Western thinkers and the public have mistakenly conflated "intelligence" and "subversion." According to Keegan, subversion is a style of warfare that ends unsuccessfully unless it is strategically integrated to an advancing army on a front. The collection of intelligence will be comprised by engaging in subversive activities, and the conflation encourages governments to militarize their intelligence agencies. Keegan disapproves of CIA's integrated structure, instead praising the British distinction between SIS (MI5 and MI6) and SAS (special forces).

Keegan's case studies include fascinating details that illustrate how the advance of technology has changed our world. For example, German cruisers during World War I were able to successfully reprovision on French islands in the Pacific by preventing radio/telegraph to them at the launch of war. Similarly, Keegan emphasizes how cartography was once the pinnacle of intelligence. The invading Union armies of the American Civil War were unprovided with any real maps of Virginia's Shenandoah Valley, enabling Stonewall Jackson to enlist local guides and create his own maps to end up where the Northerners least expected. But that problem continued through to the 1980s, where Keegan reported a SAS unit refused a mission against an Argentine airfield after learning the mission was planned based off a 1939 map (the most accurate the British had at the time).

Keegan's descriptions of how the Poles and Britons decrypted the Nazi Enigma Machine are remarkably prescient today as well, however. Much of modern cybersecurity has its antecedents in what was accomplished at Bletchley Park.

[Stephen · Rating 3 out of 5]

While I found Mr. Keegan's book insightful I do not believe it lived up to its title. Intelligence in War: Knowledge of the Enemy from Napoleon to Al-Qaeda did not provide an in-depth insight into the art of intelligence and how it was used in war, so much as it was historical retellings of campaigns and battles that served as turning points in various wars.

For example, a short few pages were dedicated to the cryptanalysis conducted by Captain Joseph Rochefort and his team at Hypo as they deciphered Japanese encrypted communications, and the subsequent deception used leading up to the Battle of Midway. While a great swath of the book described the actual Battle of Midway in significant detail.

If you are interested in a book that breaks down various battles in detail and providing historical context for the significance of these battles, then this is a great book. I was looking forward to reading more about the craft of intelligence, and how it was utilized in the art of war throughout history.

[Katie · Rating 4 out of 5]

With Intelligenve in War, Keegan continues to display his all-encompassing knowledge of military history, and makes another brilliant contribution to the study of warfare. Whilst certain sentences (especially in the first few chapters of the book) were difficult to read, the book itself is relatively simply set out, as Keegan evaluates a dozen different case studies of the subject matter. His conclusion (that whilst intelligence may be able to help a war, it is always secondary to brute force), runs powerfully and convincingly throughout the book.

[Christofer Hydos · Rating 3 out of 5]

Keegan's thesis doesn't feel supported by the body of his text. While the individual accounts were interesting in their own right I didn't get the sense they were adding to any overarching argument. This book could be more accurately described as an anthology of intelligence gathering throughout the centuries.

[Huw Evans · Rating 4 out of 5]

What is the value of Military Intelligence in warfare? This is the question that John Keegan asks in this book and he cites a number of episodes where the speed, value and access to information of the opposition improves with enough potential to change the outcome of a battle or campaign.

Having read much by other military historians of late I had forgotten just how dry, stylistically, Keegan is. He is also, of his own admission, much more interested in deployment than intelligence which would appear to bias the way he answers his own question. However, he raises some fascinating insights into the development of warfare over the centuries. How the hell did two navies actually find each other when you consider the vastness of water upon which they are searching? Did the advent of wireless communications actually improve the situation? By selecting the historical events he does it can be argued that he uses these to justify the point he is trying to make. There may well be other (unknown to me) examples that counter his argument equally successfully. There is, however, the basic truth that the more you know in advance of the engagement the more likely you are to be able to be able to deal with your opponent - until he makes his first move. At this point, all bets are off.

By no means is this the best thing that Keegan has written but he remains thought provoking and insightful.

[Gulo · Rating 1 out of 5]

Keegan, a widely renowned war historian, fell short in his attempt to delve into the values and limitations of intelligence in war. In fact, there was little actual discussion about the use of intelligence in war and more focus on only detailing entire conflicts as case studies (as a historian would); where the author truly failed is in tying the case studies together in any way. Furthermore, his writing style is unnecessarily challenging with such choices as excessive use of commas yet, oddly, without use of the oxford comma.

My one takeaway quote:

“War is not an intellectual activity but a brutally physical one. War always tends towards attrition, which is a competition in inflicting and bearing bloodshed, and the nearer attrition approaches to the extreme, the less thought counts. Nevertheless, few who make war at any level, from commander to soldier in the life of battle, seek to win by attrition. All hope for success at lesser cost. Thought offers a means of reducing the price.”
-J. Keegan

[Alexander · Rating 2 out of 5]

I love John Keegan. He is fantastic, and what usually makes him fantastic is not completely evident in this book. Usually he has a way of making war really exciting, while not getting carried away in the glorification of it, but this fails. Although moments are fascinating for the most part this is not worth a trip to the library.

I would have rather reread The Mask Of Command or The Face of Battle

[Matthew · Rating 4 out of 5]

This is a superb work on the role of intelligence within warfare. Keegan's chosen case studies are: Nelson in the Mediterranean; Jackson in the Shenandoah Valley; wireless technology in the First World War's naval battles; Crete, Midway, the Battle of the Atlantic, and Peenemunde in the Second World War; and the Falkland Islands in the Cold War. Insights about other events from the Napoleonic Age to the world of today are consistently sprinkled throughout. This is an excellent book that could easily have some of its material worked into a history class that actually still deals with history.

[Vahn Parsons · Rating 5 out of 5]

A thorough, comprehensive analysis of key developments in the world of military intelligence across time. Keegan does tend to display a natural bias toward historical conflicts the author is an expert on or personally interested in, but the lessons learned are timeless. This work describes the often cyclical and mutually dependent relationship between intelligence and combat power. No blind praise for the role of information, and an acknowledgement of the chaos that is the fog of war, the thesis of this work is that quite often luck and timing can play just as important a role as intelligence in the outcome of any given battle.

[Roy · Rating 4 out of 5]

"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."

This is an unusual book in that I enjoyed and was annoyed by it in about equal measure. I had a similar reaction to The Pity of War: Explaining World War I. Both are books that establish a clear thesis, make their case well, provide fascinating historical case studies relevant to the thesis, but, for me, eventually make their arguments too general, too inflexible, and are too unwilling to claim that everyone else is just missing the point.

The major case studies on the role of intelligence in key campaigns -- the British pursuit of the French Fleet to Egypt, the Shenandoah campaign of Stonewall Jackson, the early South Atlantic German/British conflict in World War I, and, in World War II, the German invasion of Crete, the Battle of the Atlantic, and Midway -- are fascinating, well done, and I think convincingly told.

Keegan reminds us of Clausewitz principles: don't expect victory just because you are well-prepared, since success depends on that but also on the commitment/spirit of the people and army, and also on a good dose of random chance. No one can argue with that, and he shows how intelligence is critical to good preparation but doesn't guarantee victory.

It is hard not to think that Keegan is reacting to what he thinks is silly talk that information and intelligence have become THE dominant elements of modern warfare. I do think he makes a case that such language is likely overdone. He also makes a good distinction that strategic and foundational intelligence (intelligence BEFORE military operations) is always important and can be determinant in whether we go to war and what kind of war will be fought. But then he argues that once military operations begin intelligence and information are only one factor among many that determine outcomes.

In my opinion, he often goes overboard in finding "but what if this had happened" examples to minimize the role of intelligence and information in military operations. He claims to prove that intelligence was not the critical element in the Battle of the Atlantic and Midway, two examples where most historians give a major role to intelligence, and where most historians believe the narrative of these battles required complete revision after the Allied codebreaking was revealed in the 1970s. I think he shows that more than intelligence was required to win (organization, commitment (Clausewitz's "will"), and a bit of luck), but doesn't really take away that intelligence was critical to both of these Allied successes.

For readers who might be interested in a particular period, I mention that the subtitle of "Knowledge of the Enemy from Napoleon to Al-Queda" is a bit misleading. This book is mainly about World Wars. There is an extended epilogue that tries to take the lessons forward from 1945 to 2010, but mostly these are vignettes compared to the case studies, with even most of that epilog devoted to the Falklands War of 1982 and the early War on Terror.

He also spends a lot of that epilogue on an argument that covert operations shouldn't be confused or combined with intelligence work, explicitly arguing that the CIA and MI-6 decisions to take on covert action and irregular warfare after WWII was a mistake. It seemed like a different topic than the rest of the book, and yet not given enough time to be as persuasive as the rest of the book.

Very readable and interesting to anyone caring about how intelligence has mattered in military operations. His basic case is very worthwhile for anyone thinking about the role of preparation for war as a part of national security -- a reminder that the modern information age has not repealed the lessons of Clausewitz Carl von. But be prepared to find the work British-centric, naval centric, and occasionally strident in trying to emphasize his message.

[Stuart Bobb · Rating 3 out of 5]

What:
====
The author takes a number of historical military events - some well known, others less so - and dissects the role intelligence played in the outcome.

Each chapter is largely independent (and some are more interesting than others for sure) but he has a summary at the end as well.

Some High Points:
==============
While the allies were reading German naval transmissions, their German counterparts in B-Dienst were frequently getting equally good decrypts on convoy information. I had pictured the Battle of the Atlantic as more one sided (to the allied advantage) when it came to intelligence, so I learned something new in that chapter.

There is a very important section on “what the Luftwaffe did wrong that the Gestapo never did” discussion around Enigma that sheds real light on just how much poor cryptography discipline by the German air force and navy contributed to Allied success.

Reasons to Read:
==============
You are curious about the role of intelligence in wartime or a Keegan fan. Being at least familiar with some of the episodes discussed will likely improve the reading, but it isn’t necessary - Keegan provides plenty of supporting detail (more on that below).

Intelligence is always valuable, but it doesn’t always accomplish what you think. The example of WWII in Crete (where decoded Enigma transmissions from the Luftwaffe gave the British a huge advantage) still resulted in the Germans achieving their objectives (though they took heavy losses). So, you can know what’s coming and when - and still fail to stop it.

Reasons to Skip
==============
If you are looking for an end to end story, you don’t get one here. Each chapter largely stands alone. That’s a strength (to me) but you might not care for it.

Perhaps, like me, you are *not* a Civil War fan - so even one chapter on that conflict (and covering a character I’m also not interested in) was too much, despite being well written. I would have preferred something else, myself.

Sometimes, Keegan gives a little more background than you might want. I don’t care for the order of battle details on how this or that division or company was deployed - it doesn’t hold my interest. Likewise, I’m betting quite a few readers will skim some of the discussion behind Enigma (Keegan explains just why it was so good and why the Germans had reason to be confident in its security - but that discussion dives deeper into the depths of cryptography than some will want to go). I think that could have been shorter.

[Antti Värtö · Rating 4 out of 5]

Three-and-a-half stars. This book is kinda disjointed and it has multiple examples it analyzes in detail, but it's really unclear as to why these specific examples were chosen, and if they are at all representative.

The book starts with Nelson and ends with the Falklands War, briefly mentioning the First Gulf War (not the second, since it hadn't started yet when this book was published). I can understand the end point: Falklands War is probably the most recent war we have enough public information about that we can draw any real conclusions, although Keegan mentions there are many documents which are still secret and that most likely contain some essential information. But why start with Nelson, in particular? Why not, I don't know, the Franco-Prussian war, or even the Roman wars, or something? There is no real explanation.

From Nelson, Keegan hops to consider "Stonewall" Jackson's fights in the Shenandoah Valley during the American Civil War, von Spee's raiding sprees in the Pacific during the WWI, the battles for Crete, Midway and Atlantic during the WWII and the espionage operations related to the Nazi V-1 and V-2 programs. As one can see, most of the examples are related to marine warfare, but not all. Again, pretty unprincipled in a way that seems almost random.

But it's not quite random, since Keegan uses all the examples to tell a different story about the role of intelligence during a war. Nelson had to operate with very little information, and thus he couldn't even find his enemy for a long time! Jackson had a much better knowledge of the area than his enemies, and thus he could win victories even with lower numbers. Von Spee could use radio, but only intermittently; in Crete, there was ample intelligence but it wasn't utilized properly; in Midway, the intelligence was top-notch and used properly, but the victory was still dependent on luck. And so on.

Keegan's thesis is that although military intelligence is useful, it's not enough to win a war; indeed, he says that only brute strength matters in the end. The war can be shorter with good intelligence, or longer it if the enemy has more information than you do, but the outcome still depends only on which side has the superior forces.

I learned a lot from this book, but I wish it was organized with a bit more thought.

[Doninaz · Rating 5 out of 5]

Keegan’s book deals with military intelligence, as distinguished from espionage: little glamour is involved, as these stories are wartime experiences. John Keegan was a military historian. His eight chapters, mostly war stories, provide meaningful lessons about types of military intelligence, where it can be successfully applied, and how it is limited.

The book is well organized. Keegan prefaces each episode with rich background, so that the main activities are clearly understood in context. The background is itself, a short history lesson. Keegan then describes the type of intelligence featured and how it was applied. At the episode’s conclusion, Keegan analyzes the value of the intelligence in that particular situation.

Keegan’s episodes span across history from Napoleonic times through World War II, revealing the wide applicability of his lessons. Keegan then adds a chapter on intelligence since World War II. He concludes with an overall analysis on the value of military intelligence.

Surprisingly, Keegan concludes that in war, intelligence often fails its expectations. Information about the enemy, his location, and his plans is often either difficult to obtain, misleading or misinterpreted, or less important than the forces being employed. Even in the Battle of Midway, a near-perfect case where broken codes revealed the Japanese fleet’s intentions, the ultimate victory owed much to chance.

Not everyone will be tolerant with Keegan’s thorough development of his episodes, but few will be disappointed with his attention to detail. His lessons are instructive and his revelations bring his scenes to life.

[Christopher · Rating 3 out of 5]

"Military intelligence" and other oxymorons.

Keegan's 2003 "Intelligence in War" is more a general interest collection of battle case studies rather than an in depth look at the role intelligence plays in warfare.

That's not to say Keegan's general premise is wrong, it's not. intelligence is a necessary, but not sufficient, element in warfare. But battles and wars can, and often are, won in the face of poor intelligence just as they are lost despite one side having clearly superior information.

Keegan rightly, if somewhat obviously, notes that success in war ultimately boils down to force, or the willingness/ ability to use it. No matter how good the information, unless a commander or state is willing to act, it's just data.

The case studies Keegan offers include Stonewall Jackson in the Shenandoah, submarine warfare in WWI and WWII, the Battle of Midway, among others. There's an extended section on the Falklands War which seems out of place but is still interesting.

The timing of the book is really the most interesting part. Written in 2003 at the height of the war on terror and the efforts to discover/ uncover Iraq's WMD program, Keegan's book is really a salvo against TV talking heads and armchair generals who loudly and piously proclaimed what intelligence was *obviously* saying/ not saying about Al Qaeda, Iraq, WMD, etc. Keegan subtly chastises such intellectually vapid approaches by noting that "intelligence" is simply information that must be interpreted and that people can reach different interpretations. And that it's not until one acts that you see whether that information, and that interpretation, was accurate.

[Tim Martin · Rating 5 out of 5]

_Intelligence in War_ by John Keegan asks a basic question; just how useful is intelligence in warfare? There is he wrote a great deal of literature that seems to suggest that it is of enormous importance but Keegan sought to show exactly just useful it really is.

First, Keegan defined intelligence. There are five fundamental stages in intelligence practice, the first being acquisition. While the data gathered may include published and publicly available information, generally information that is useful in a military situation is gathered through clandestine means, the main types being spying with human agents (human intelligence or humint), the interception of an enemy's communications, a method generally requiring decryption (signal intelligence or signit, the main type of intelligence discussed in the book), and visual imaging or surveillance, through aerial photography provided by aircraft and satellites. Throughout the book Keegan discussed the pros and cons of each type of intelligence and their relative importance over the years. Second, there is delivery (something nontrivial especially for the transmitter of humint). A major problem for centuries was the difficulty in sending collected intelligence to a potential user in a timely fashion, in "real time" (a major problem before the telegraph). The third stage is acceptance of the gathered intelligence, of either accepting the source or believing instead that the information is wrong or in fact is an example of enemy counter-espionage. The fourth stage is interpretation, the art and science of weaving together a picture from the many scraps collected to produce a useful picture of an enemy's capabilities and intentions. Finally is implementation of this intelligence.

The bulk of the book is a collection of case studies, examples that Keegan took from history to illustrate various points about the collection and use of intelligence and how these points are still applicable to the modern policymaker. He began in the age of sail, when the main difficulty in the intelligence field was in the struggle to acquire useful information and deliver it to intelligence officers at such a speed so it wouldn't be out of date, and ended near the present, when there is such a vast wealth of information of all sorts - "frustratingly rich" as Keegan put it - that the volume threatens to overwhelm the minds of those seeking to evaluate its worth.

The cases Keegan chose were extremely interesting and very well-told stories, ranging from Admiral Nelson's chase of Napoleon's fleet in 1798 that culminated in the Battle of the Nile to the use of intelligence in the 1982 Falkland Islands War, each case study well illustrated with photographs and excellent maps. Though each case study could simply be read as a detailed and well-written historical account, they also served to illustrate various points Keegan was making about intelligence in war.

For instance, the German airborne assault of Crete in May 1941 vividly showed that even the best intelligence in the world is no good if the defense is unable or unwilling to profit from it. Despite nearly real time intelligence provided to the commander of Allied forces on the ground in Crete, including the timing of the attack, the objectives, and the strength and the composition of the attacking force, the Germans won the day. The Germans won by a combination of extreme nearly berserker recklessness on their part and the belief of the local Allied commander that he could successfully retire, regroup, and counterattack after a bit of rest at one part in the battle, leaving a small opening that the Germans were able to exploit, something that they should have not been able to do. This illustrated two points that Keegan made several times in the book; one, that no matter how good the intelligence, that given equality of force, the outcome will still be decided by the fight, and that in a fight, again given equality of force, the outcome will be the result of determination.

The Battle of the Atlantic - the struggle with the U-boats in World War II - has long been cited as an example of the victory of intelligence use, but Keegan showed that while intelligence was very important, one should not overlook the parallel importance of non-intelligence factors. Though Bletchley Park has been lauded for its ability to break Enigma and route convoys around U-boat wolfpacks and patrol lines, other factors played as big or a bigger role in an Allied victory, including an increase in the size of the merchant fleet, vast improvements in the technology to detect and destroy U-boats, improvement in the capabilities and numbers of escorts, and the advent of escort carriers.

The British coming to terms with the German V-Weapon program illustrated the importance of interpretation and the pitfalls of photographic intelligence. Despite a number of over flights of Peenemünde - the test center for the V-weapons - and ample photographic surveys and despite humint pointing to radical new weapons programs being developed there, the British were slow to understand what was going on at Peenemünde chiefly because the British intelligence apparatus lacked any practical knowledge of either rocket or cruise missile technology and did not know what to look for nor realize what they had in fact seen. In truth the aerial surveys had photographed equipment related to the V-weapons as well as the V-weapons themselves but the intelligence officers did not know what they were looking at and/or dismissed it, with such policymakers as Lord Cherwell insisting that any German rocket be a huge, slow-speed, solid-fueled, multi-stage rocket requiring a huge launch tower, rather than looking for or accepting the existence of a smaller, high-speed, liquid-fueled weapon requiring only a very small launch apparatus.

So what did Keegan conclude? Intelligence is important in war, there is no doubt, but good intelligence does not "unerringly point the path to victory;" that while it is necessary, it is not sufficient to ensure success. Willpower often counts for more in warfare, intelligence only being useful when there is the strength and the will to use it.

[Rebecca Yin · Rating 3 out of 5]

Intelligence in War, written by John Keegan, is supposedly a research book discussing predictably, the usage and efficacy of intelligence in winning wars. However, though Keegan speaks extensively on multiple historical skirmishes across several countries and cultures, I find that the direction he takes is more often than not simply an extremely long summarization of circumstances, with minimal mention of any intelligence collected by the officers in command of the battles. The thesis of this publication is that intelligence, while useful, “does not point out unerringly the path to victory”. Though well supported by research, this thesis still presents an idea that anyone who has even a superficial proficiency in military history already knows, and that no historian in recent memory would contradict.
Keegan prefaces his research by admitting that before publication, he had very little practical knowledge of the role intelligence has played historically, and very little interest in the subject. In my opinion, his writing is extremely transparent in this regard; Keegan spends as little time as possible explaining the different kinds of intelligence that exist, and I had to independently research the terms that he actually covered.
Based on case studies of specific conflicts throughout history, Keegan jumps from example to example in each chapter, with minimal explanation as to how acquired intelligence, or the lack thereof, actually turned the tide of the battle or conflict. For example, in the first chapter of his presentation, he begins with a brief mention Alexander the Great’s invasion of the Persian Empire, in which he used the regional intelligence gathered from his youth to exploit internal divisions and conquer the empire based on the fractures he created. However, in this case the intelligence used was actually integral to the success of his campaign, and therefore directly contradicts Keegan’s proposed thesis, especially with the following assertion that regional intelligence “underlay many of the greatest exploits of empire building” (Keegan 22). Keegan fails to elaborate on any other factors that may or may not have impacted the tide of battle, and his focus on strategic intelligence across multiple campaigns barely constitutes any kind of focus at all. Even his explanation of the Mongolian Muslim campaigns in the 13th century, which largely used a strategy focused on terrorizing the public, barely elaborates on their specific strategy. Even the longest paragraph, detailing the Roman intelligence system barely scratches the surface in terms of its interaction with the battles the imperial army fought in its heyday. And when he does cite a specific example, his explanation of the Roman-Gaul conflict does not explain other factors involved in the conflict that resulted in a Roman victory. In fact, Keegan writes in depth on how Caesar went to “ 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, [and] lack of resilience” (23).
Ultimately, though it is quite obvious what Keegan is trying to do with his research, in practice his writing falls short. The majority of the text is just an in depth description of military warfare in history. Though Keegan does make some mention of factors beyond the acquisition of quality intelligence, he does not, in my opinion, effectively draw conclusions about what his research is saying. Furthermore, in some cases, Keegan fails to make any mention whatsoever of intelligence during a conflict, which, because his work is about the indecisiveness of quality intelligence in military situations, is kind of a necessary mention if one wants to prove this particular point. Had I written this book, I would have without a doubt mentioned battles that had a significant element of intelligence involvement, as opposed to Keegan’s method, which was to attempt to detail battles that had little to no intelligence involved, or to minimize the true impact of having access to such intelligence. However, more often than not, Keegan described battles and conflicts that had a degree of intelligence, and some in which the acquisition of high quality, reliable intelligence was actually indispensible to the victors of the battle. Ultimately, I found this book to be a bit disappointing. While good for someone who is looking to get a cursory background in military strategy, it does not really cover the role that intelligence plays as its title would have one believe.
By calling into question the true value of intelligence in wartime situations, Keegan also calls into question the value of practices such as torturing prisoners in Guantanamo Bay, or in any such situation. If, as John Keegan asserts, “war is ultimately about doing, not thinking,” (436), he completely discounts military strategies within the intelligence community (CIA, NSA, Mossad, etc.) that involve the torture of prisoners of war during international conflict. Even with the idea of and “ideal of military intelligence, when one side is privileged to know the other’s intentions, capabilities, plan of action in place and time”, the British still lost the Battle of Crete against the German airborne invasion in 1941. As such, Keegan points out a sobering reality: even with the most thorough and high-quality intelligence, unless a force is thoroughly prepared for and well matched against the invading force, there is absolutely no chance that the attacked can properly be defended. Though it is a common-sense kind of conclusion, Keegan points out that intelligence will never be a deal breaker in terms of who wins a war. Much like we discussed earlier in the year, Keegan concurs with the suggested inefficacy of any previously acquired knowledge, especially if the defending force is in a position of “strategic inferiority”, as Keegan calls it (440). This means that even if the CIA managed to extract any valid information from captured terrorists or prisoners, should we still be ill equipped to protect against certain types of attacks (biological warfare in a suburban setting, for example) we would still lose the battle, much like we concluded in class.

[Michael · Rating 2 out of 5]

I confess myself a bit disappointed.

The main reason I picked this book up was due to the title. I was an intelligence professional myself and was rather looking forward to reading what someone of Keegan’s caliber had to say on the matter. Most of what I read appeared more as filler than any real information on the world of intelligence.

The chapter I looked forward to the most was the biggest disappointment (Human Intelligence Collection). There never was anything remotely close to a coherent narrative about the subject. No mention of how interrogations and source operations have changed over the years, or about how it is the one of the more favorable means of intelligence gathering in modern warfare. Even a simple google search would have led to information about Hanns Scharff the Nazi interrogator that changed the way interrogations were conducted, such as pioneering the change of location technique.

Anyone looking for information on intelligence in war is better off looking elsewhere.

[Aranka · Rating 3 out of 5]

This book falls short of the expectation set by the title. It is supposed to be analytic, to debunk the myth of intelligence. But to my dissappointment, it was a very pure textbook-like illustration of military history. There is virtually no demystification - in fact the author said in the book that many military innovations/technologies have been kept secret. And they surely will not be revealed here.

The main point that the author wanted to make from the whole lot of historic events is that intelligence does not determine the outcome of war. Just reading the beginning and end is enough to get the whole analytical picture. Several interesting points were made in the beginning and applpicable to other areas:
- Don't look for information accessible from public sources to include in intelligence;
- Intelligence is only useful when sent to an audience;
- Intelligence is highly scattered and unsystematic;
- It can be a mundane work.

[Hans · Rating 3 out of 5]

The author takes some historical battles, ranging from Nelson chasing Napoleon's ships in the Med to the Falklands war, and shows what role intelligence played during these battles. There are a number of case studies that were interesting to read. But I found the introduction of the book and the first two chapters hard to read and get into. Later chapters were, in my opinion easier to read and follow.
In part this can be explained by me being unfamiliar with Napoleonic naval battles and my limited knowledge of the American Civil War.

What the book does succeed in doing quite well is showing that gaining intelligence on the enemy is of importance, that even then there is still a battle to be won. In the case of Crete and Midway, both WWII examples, there was good intelligence on the enemy plans or positions. But in the end it was luck and/or bad luck that won the battle.

Interesting book, but I had expected more of it somehow.

[Peter Fox · Rating 2 out of 5]

This is far from Keegan's best work.

For a book on intelligence, it features less than what you'd expect. There is a lot of historical background, a bit on how the intelligence was gathered, some space is then given to how the intelligence is used, but it feels more like a series of snapshots of campaign history.

The first two chapters, Nelson and Stonewall Jackson, quickly get repetitive, as they recount the movements of ships and troops to the point where you're heartily fed up of hearing who marched (or sailed) where and when.

Coronel is interesting, but more so because it is fairly obscure. Crete made the good point that knowing the enemies intentions isn't decisive in itself, as you still have to win the battle. Midway, again felt like a war story, as did the Atlantic. The V weapons chapter was ok, but again, mostly about context.

The final chapter, apart from the Falklands section, felt rushed.