This review was published in War in History, pp.18-2, in April 2011, by Sage Publications Ltd., All rights reserved. ©Bruno Colson. Posted to The Clausewitz Homepage by permission of the author and of Sage Publications.
Colson, a very well known Belgian historian of the Napoleonic Wars, is also the author of a recent French-language biography, Clausewitz (Paris: Perrin, 2016). See the very positive review by Peter Paret, "Clausewitz's Life and Work as a Subject of Historical Interpretation," in The Journal of Military History 81 (July 2017), pp.829–837. Colson's ground-breaking book Napoleon: On War (Oxford University Press, 2015) has been carefully organized to follow the framework of Carl von Clausewitz's classic On War, allowing a fascinating comparison between Napoleon's ideas and those of his great Prussian adversary and interpreter.
See also Colson's review of On Waterloo: Clausewitz, Wellington, and the Campaign of 1815.
Clausewitz and Contemporary War. By Antulio J. Echevarria. Oxford University Press. 2007.
Clausewitz’s Puzzle: The Political Theory of War. By Andreas Herberg-Rothe. Oxford University Press. 2007.
Carl von Clausewitz’s On War. A Biography. By Hew Strachan. Atlantic Books. 2007.
Clausewitz in the Twenty-First Century. Edited by Hew Strachan and Andreas Herberg-Rothe. Oxford University Press. 2007.
Clausewitz en France. Deux siècles de réflexion sur la guerre 1807-2007. By Benoît Durieux. Economica. 2008.
The Cognitive Challenge of War: Prussia 1806. By Peter Paret. Princeton University Press. 2009.
The years 2007 and 2008 have seen a blossoming of new books on Carl von Clausewitz and his major work, Vom Kriege (On War). Besides the books covered by this review, other ones have been published in the United States and in France, where the Prussian thinker was the subject of an international conference at the military school of Saint-Cyr in November 2007. One can speak of a new wave in Clausewitz studies, after the one centred on the widely used 1976 translation of On War by Michael Howard and Peter Paret.
In many respects, the new wave is a reaction to a Cold War vision of Clausewitz. Among the common features of recent studies on Clausewitz, there is a tendency to balance the primacy of politics in war, expressed in the famous dictum of Book 1, chapter 1 of On War: ‘war is nothing but a continuation of politics by other means’. Where Howard and Paret read ‘policy’, the new wave sees ‘politics’. This implies a less rationalistic view of war, which is always related to politics but can escape the control of policy. The emphasis is laid on another definition of war mentioned later in the same chapter, the ‘wondrous trinity’ which is ‘composed of primordial violence, hatred and enmity, and probability within which the creative spirit is free to roam; and of its element of subordination, as an instrument of policy, which makes it subject to reason alone’. On War was not completed by Clausewitz when he died from cholera in 1831 and Book 1, chapter 1 had for a long time been considered as the only expression of Clausewitz’s final thinking. Israeli historian Azar Gat had already noticed in 1989 that the other books of On War may not have been as unfinished as previously thought. What definitely necessitated a re-examination of Clausewitz was the new kind of war encountered in the post-Cold War world. Sub-Saharan Africa, Afghanistan, Iraq and terrorism led some analysts to call Clausewitz obsolete and irrelevant. Wars didn’t follow the classical pattern of an armed conflict between states any more and a work conceived in this context, just after the end of the Napoleonic wars, would just remain an historical piece. Others saw it differently.
Andreas Herberg-Rothe is a private lecturer at Humboldt University, Berlin. Clausewitz’s Puzzle is a shortened translation of a book published in Munich in 2001. It argues convincingly that three military campaigns experienced by Clausewitz are central to an appropriate understanding of On War: the Jena-Auerstaedt campaign of 1806, the 1812 campaign in Russia and the Waterloo campaign in 1815. Clausewitz wrote detailed accounts of these campaigns between 1823 and 1827, while he composed On War. So Books 3 and 4 (about strategy and combat) mainly reflect 1806, Book 6 (about defence) is mainly derived from 1812 and Book 8 (about war plans and politics) from 1815. Only in Book 1 and at the beginning of Book 2, does Clausewitz succeed in finding a common denominator to these contrasting historical experiences. By reflecting on the success but also on the limitations and on the failure of Napoleon’s experience, he went beyond purely military matters and was able to develop a wide-ranging political theory of waging war. The ‘wondrous trinity’ is the final result of this development and his true legacy. The humiliating Prussian defeat in 1806 shook him to the core. Realizing that previous conventional theoretical limits were no longer relevant, he developed four ideas: ‘an existential conception of war; the inherently unlimited violence of war; an orientation towards the primacy of the attack at all costs; and, in Clausewitz’s early writings, the prioritization of military success over ideals and politics (understood in civilian terms)’ (p. 27). These ideas were challenged when Clausewitz, in 1812, left the Prussian service to fight against Napoleon in the Russian army. The campaign in Russia led him to qualify his previous view of the exemplary character of Napoleon’s strategy. An offensive strategy was not suited against Russia, although it had succeeded against Austria and Prussia. ‘The Russian campaign could not have been won, however it might have been waged’ (p. 31). Clausewitz, says Herberg-Rothe, became aware of a fundamental limit of warfare. The door was open for the next step, following the experience of the Waterloo campaign: the discovery of the primacy of politics over warfare. Napoleon was defeated in the first place because of domestic and external political circumstances, which decided the outcome in advance. Domestic political weakness prevented Napoleon from calling a greater number of men to service and from waging a defensive war on French soil: the only course of action open to him was an offensive outside French territory. In terms of foreign policy, the French army was confronted by a coalition able to mobilize many more men and guns. The theoretical shift that drew Clausewitz to the primacy of politics during the years 1827-1830 resulted from his analysis of these three contrasting campaigns, carried out during the same period. Clausewitz then decided to revise his entire work. He had found antitheses in the study of Jena, Moscow and Waterloo. He developed a synthesis in chapter 1 of Book 1 and that constituted the basis of his theory of war. Politics is a first unifying concept which explains the diversity of wars and campaigns. But this conceptualization is only one of three tendencies within the ‘wondrous trinity’, and these tendencies are of equal importance. They describe different dimensions which, in each individual war, act together as a whole. ‘Depending on the historical situation, the external circumstances, and the decisions taken in each case, one or other of these poles comes to the fore at the expense of the others’ (p. 117).
We can admit that after the defeat of Prussia in 1806 Clausewitz saw ‘escalation’ as a way of waging war successfully. But some words have to be used with caution. Herberg-Rothe shouldn’t have written that Clausewitz ‘speaks of total war’ (p. 42). The expression has been so much used and debated recently by historians that he should have found another way to express ‘outdoing the enemy by partisan warfare’. He does two pages later when speaking of an ‘expansion of warfare’. He also rightly distinguishes it from ‘the extreme as only a logical consequence of unrestrained warfare’ which is ‘purely notional and abstract’ (p. 44). Clausewitz noted a real tendency in war: the intensification towards extreme and limitless force. Like Herberg-Rothe, the French philosopher René Girard insists on this intellectual discovery by Clausewitz and this is one of the main arguments of the new wave. Herberg-Rothe rightly points out in Clausewitz the contradictory factors represented by violence, fear and power in war: they can lead to the extreme but they can also have limiting effects. Herberg-Rothe is a philosopher and he is sometimes hard to follow in his discussion of concepts, as in many works and papers on Clausewitz’s ideas, but less here than in most of them. One reason is that he always goes back to Clausewitz’s historical experience and this strengthens his demonstration. He notes for example that the remarks about friction in Book 1 originated in the analysis of the Russian campaign, from which they are taken almost verbatim. So we understand how this gigantic campaign modified Clausewitz’s view of warfare. Some considerations could nevertheless have been shortened. There are also needless repetitions of the same argument. On the whole, Clausewitz’s Puzzle is a very useful book, clearly written and bringing fresh light to the subject.
Hew Strachan’s Carl von Clausewitz’s On War has the same qualities and more. In quite a concise manner, this book gives a full state of the art of Clausewitz studies and as such it should be recommended as a starting point for everyone interested in the field. Sources and further reading are commented in the last pages and cover the whole field in every major language. The introduction is devoted to people who read or misread Clausewitz, from Jomini to Colin Powell. On War is open to many and Strachan stresses the bias of the rationalist school, clearly setting his own study at the forefront of the new wave. This does not bring him to underestimate the work done by Howard and Paret but historians are themselves subjects of history and they see war through the lens of their own time. Since the 2003 war in Iraq and the inability of the US government to achieve its objectives over the years, war is no longer easily seen as a trustful instrument of policy. Strachan has very well turned phrases to characterize Clausewitz’s work. He doesn’t see his other writings as separate from On War but as ‘the anvil on which the ideas were forged’ (p. 26). Strachan’s book develops through four chapters. The first one is devoted to ‘The Reality of War’: the military career of Clausewitz, his campaigns and the evolution of his ideas about war. After the Prussian defeat of 1806 and the reforms undertaken by Scharnhorst, Clausewitz decided in 1812 to leave his country and to offer his sword to the Tsar of Russia. His view of war was existential at that time: it had its own purpose, which could be fulfilled even in case of defeat. This is the Clausewitz who appealed to the Nazis, especially in 1944-45. ‘The Writing of On War’ forms the second chapter. The first and posthumous edition of On War, as Strachan reminds us, underwent interventions by Clausewitz’s brother in law, General Wilhelm von Brühl, and by Major O’Etzel, from the war college. We will never know their extent as we no longer possess the original manuscript from which they worked. Strachan agrees with Werner Hahlweg on the fact that Clausewitz, as he said in a note dated from 1827, had the time to revisit not only Book 1 but also Book 8. His approach ‘was to write organically, constantly rethinking which chapters—which insights—belonged in which books, shuffling material between books, building up observations, but then striving to pare down his prose, so that the results were succinct and aphoristic’ (p. 79). This very good description acts as a warning for anyone intending to read On War for the first time.
Strachan shrewdly situates Clausewitz gradually shifting from the Enlightenment to Romanticism, while always retaining some aspirations from the former. As an historian, Strachan dismisses some distinctions made by political scientists in Clausewitz’s terminology, like Ziel and Zweck: the consistency of the distinction is not evident. Clausewitz often changes the words he uses to designate the same thing. ‘On War’s vitality rests in its spirit of enquiry’ (p. 105). Strachan brilliantly shows how apparent shortcomings actually craft the enduring value of On War. Chapter 3, ‘The Nature of War’, examines the core of Clausewitz’s ideas and basic concepts. For him, changes in tactics led to changes in strategy. Strachan says the reverse was not true, contrary to ‘Camon and pre-1914 students of Napoleon believed’ (p. 117). French General Hubert Camon indeed wrote numerous books on Napoleon’s strategic manoeuvres and said almost nothing about tactics. But he was not the official expression of French doctrine. The latter, taught at the Ecole supérieure de Guerre, was primarily devoted to tactics. A Swiss historian has recently published the first in-depth study, based on his doctoral dissertation, of the evolution of French doctrine from 1871 to 1914. This doctrine taught by Lewal, Bonnal and Foch—to name but a few—was primarily tactical. Among Clausewitz’s concepts, the ‘centre of gravity’ has attracted a lot of attention, especially in American military journals. Strachan has an answer and it’s the right one: the conception ‘grew in sophistication as the writing of the book proceeded, and according to the level of war which he was addressing’ (p. 132). This has escaped many readers. Book 4 of On War bears the German title Gefecht. This is usually translated in English by ‘the engagement’. And the same holds for French, where the same word is used. But there is now a tendency in French to use combat for Gefecht. If one prefers to reserve the English term ‘combat’ for Kampf in German, there is still ‘fighting’ to translate Gefecht and this comes probably closer to Clausewitz’s thinking than this vague term of ‘engagement’. Strachan’s last chapter is entitled ‘The Theory of War’. According to him, Clausewitz’s focus was less on the issue of military subordination than on civil-military harmonization. One cannot escape thinking about the situation in Iraq at the beginning of the 21st century when one reads that ‘those responsible for policy need to have sufficient grasp of war’s true nature not to make demands of war which war cannot fulfil’ (p. 168). Reacting to the liberal reading of On War, Strachan underlines that the effect of policy on war is not necessarily to limit war. To fight against Napoleon, Prussia had to raise the level of war in order to harmonize it with the political aim of national liberation. Strachan gives a new and illuminating explanation of the ‘wondrous trinity’. He sees in fact two trinities, one of ‘moral attributes’ (violent passion, probability game, reason) and one of ‘specific actors’ (the people, the general and his army, the government). In war the two groups clash which each other and it is the conflict between the three elements of each that generates the scope for friction and escalation (p. 179). We can thus have a large variety of situations and these are not always dominated by reason.
Similar arguments can be found in Antulio J. Echevarria’s study on Clausewitz and Contemporary War. As indicated by the title, the main stress lies on the practical utility of Clausewitz today. The author is Director of Research at the Strategic Studies Institute of the US Army War College. But the aim is first to understand the purpose of On War, its methodology and what Clausewitz meant by a theory of war. Comments in relation with contemporary use of force come only in the conclusions of chapters and sections. The book is a thorough analysis that can be useful not only for the military but also for historians, political scientists and politicians. It is clearly written, with rather short chapters allowing the reader to ponder over and breathe. The material is, as expected, quite difficult and abstract. A lot of false assertions are corrected. At some points we could suspect the author of being too fond of a sort of paradoxical reappraisal but we have to admit that he is right most of the time. This is the case with what Clausewitz called laws. If those which prescribed action had for him no place in military theory, he thought of laws of war in a different sense, as fundamental cause-and-effect relations that explain why things happen the way they do in the real world, as the law of gravity or the law of motion. Discovering these and organizing them in a corpus of scientific observations was the theoretical purpose of On War. For Clausewitz, fighting (das Gefecht) is the highest law of war. Fighting is the key ingredient that distinguishes war from other social or political phenomena. His theory is combat-centric, in the same way as Copernicus’s planetary system revolved around the sun. Next in the hierarchy, there are principles like the one of mass which governs certain operations in war. It is more flexible than a law and applies to a more limited field. Then come the rules, less authoritative and admitting exceptions, and finally the regulations and the procedures, designed to work in most situations and especially valid at the lower ranks. Clausewitz’s understanding of ‘objective knowledge’ is derived from Kiesewetter’s lectures on the Kantian system delivered to him at the Institute for Young Officers in Berlin. Therefore Clausewitz was less concerned with showing us how to think about war than with establishing this corpus of firm knowledge to serve as a foundation for our thinking, ‘a platform from which to spring from objective to subjective knowledge’ (p. 26). The latter refers to skill in judgment (Takt), the innate talent of great generals, something more difficult to acquire. To arrive at objective knowledge, Clausewitz used Kiesewetter’s applied logic: he worked with pairs of ideas, dualisms, contrasting the opposites in order to go beyond appearances and to explore the substance of concepts. This effort made On War less accessible but more enduring. For Clausewitz, the nature of war meant the sum of the fundamental cause-and-effect relationships, or laws, which defined it.
As other members of the new wave, Echevarria advocates the trinitarian view of war instead of the one dominated by policy. The wondrous trinity, he says, ‘negates the notion of the primacy of policy’ (p. 95). The German word Politik encompasses not only the political conditions of the era, but also its dominant ideas and conventions and the ‘spirit of the age’ or zeitgeist. It is in sum a deterministic force that shapes history and actually, says Echevarria, ‘severely restricts policy choices’ (p. 91). He goes on: ‘If we view war primarily as an act of violence with a tendency to spiral out of control, we may use it sparingly, or not at all. If, on the other hand, we see war largely as an obedient instrument of policy, we may try to use it to achieve a great deal, perhaps too much’ (p. 58). Clausewitz takes the example of the Tartar tribes : he doesn’t think only in terms of the nation-state model. When he refers to the Waterloo campaign as an example of the influence of Politik on war, his argument has effectively less to do with the primacy of policy than with the deterministic influence of politics, broadly defined. For Echevarria, Clausewitz’s combat-centric theory of war, in which the threat of combat can replace combat itself, is still valid as a foundation for the type of mission military forces are performing in the post-Cold War world. There have been different interpretations of the ‘centre of gravity’ in the American military and naval literature. The concept does not refer to key vulnerabilities neither to sources of strength. It is the thing that, if struck by you, would lead you to decisive victory. As in elementary physics, taking the centre of gravity away should cause the object or individual to collapse. This must encourage more thorough thinking regarding the goals that policy makers and military commanders wish to achieve. However unfinished and subjective Clausewitz’s truths may be, they remain interesting in order to test our own. Echevarria has succeeded in convincing the reader, as he said in his Introduction, that ‘Clausewitz’s On War is as critical to our basic knowledge of war as Nicolas Copernicus’ On the Revolutions of the Heavenly Spheres is to astronomy’ (p. 2).
For those who would remain sceptical, the proceedings of a conference held at Oxford University in March 2005 should settle the matter. This 319-page book, entitled Clausewitz in the Twenty-First Century, brings together sixteen individual contributions which show the vitality of the Clausewitz studies. As always with proceedings, some papers have more weight than others. The perspectives embraced are those of historians, philosophers and political scientists. Some of them teach in universities, others in military academies or military colleges. The contributors include several American and British academics, but also six Germans, an Argentine and a Frenchman. This is proof of the Renaissance of Clausewitz in his own country but, significantly and unfortunately, there is no historian among them. They are all either philosophers or political scientists. Nobody seems to have followed the great Werner Hahlweg. Sir Michael Howard opens the book with an interesting remembrance of the vicissitudes of the translation of On War he published with Peter Paret in 1976. Their intent, he says, was to present a text accessible both to military colleges and to university students. The success of this translation was and still is enormous. As the editors Hew Strachan and Andreas Herberg-Rothe say in their Introduction, ‘when many English-language scholars discuss On War, they are in reality discussing Howard and Paret’s interpretation of it’ (p. 13). Strachan adds that ‘On War now has greater coherence and readability in English than it does in its native German’ (p. 33). He tells a very vivid and comprehensive story not only of this translation but of the numerous readings and interpretations of On War, bringing material which was not developed in his own book commented above. He identifies the ‘crisis’ of Clausewitz studies at the beginning of the 21st century as a direct product of the Howard-Paret translation, with its emphasis on Book 1, chapter 1 (war as a continuation of policy). French-speaking people would add the name of Raymond Aron. His analysis of Clausewitz’s magnum opus was impressive and, for some time, seemed definitive. As Strachan notes, interpretations of Clausewitz have differed generationally, nationally, and politically. ‘None of his interpreters has necessarily misquoted him’ (p. 37). The second essay is from Alan Beyerchen who made such an important and lasting contribution with a previous article. He adds little new here but underlines the place of science in the vocabulary of On War and the intuition Clausewitz had of what we now call non-linearity. This is a good way to highlight Clausewitz’s ideas.
Problems of text and translation are crucial for understanding On War. Jan Willem Honig gives useful indications in this respect: the original manuscript on which the first edition was based has been lost; Werner Hahlweg has only been able to publish some drafts and preparatory works. He also produced the best possible edition in German, based on the first one. Honig then turns to the vocabulary of On War. Howard and Paret, he says, had wanted to emphasize the modernity of the text and they translated Niederwerfung, for example, by ‘defeat’. But the word has the stronger sense of ‘overthrow’. The ‘liberal’ translation led to a softening of Clausewitz’s language. Similarly, the rendering of Politik by ‘policy’ suggested that there was a tool at hand enabling us to control war. Christopher Bassford, in another contribution, goes on surfing on the new wave and he points to the trinity as the central concept in On War. He interestingly identifies four broad schools in Clausewitz studies: ‘the original intent school’, in which historians focus on Clausewitz and his writings in the context of their time; ‘the inspirationist school’, including political scientists or business theorists who freely use Clausewitz’s ideas to analyze current issues; ‘the receptionist school’, also composed of historians who study the impact of Clausewitz on later generations, as Bassford did with his Clausewitz in English; finally ‘the editorial school’, eager to convey what Clausewitz really meant when he wrote as he did. Of course, says Bassford, many tend to straddle these various schools according to circumstances. However, he doesn’t say where he places philosophers and sociologists who try to understand and explain On War without an editorial intent. I presume he puts them in the inspirationist school. In the trinity, he criticizes the translation of mehr by ‘mainly’ instead of ‘more’ by Howard and Paret. His argument is lexicographically correct and this distortion had the effect of linking too firmly and exclusively the violent emotion to the people, chance and probability to the commander and his army, and rational calculation to the government. If these associations are broken and if other combinations are allowed, we have a much more promising model to understand the inherent unpredictability of war. Still in the same book, the German philosopher Ulrike Kleemeier sees in Clausewitz a theorist of ‘emotional intelligence’. He was aware that action in war demanded an intuitive way of thinking and his insights have deeply influenced German conceptions of military leadership. Intellect is insufficient in war; combined with emotions, it can be transformed into action.
In a former article, Jon Sumida stated that Book 2 of On War had been unduly neglected and that it was in fact its true axis. At Oxford he contended that Book 6 was essential and that the unifying concept of On War was the proposition ‘defence is the stronger form of war’. Perhaps he makes too much of this argument, seeing it everywhere. Of course everyone’s ideas evolve and many nuances may be missed on a first reading. One has to go through the book again and again. It is a matter of fact that Book 6 is twice the length of most of the other books. Christopher Daase, who teaches International Relations at the University of Munich, goes beyond On War and looks at one of Clausewitz’s manuscripts, the Bekenntnisdenkschrift, or memorandum of confession, from 1812, which outlines a comprehensive guerrilla strategy in Germany against Napoleon. We find there interesting tools to understand terrorism and small wars. Clausewitz said for example that the escalation dominance is always in the hands of the insurgents since the state would be the first to quit the ‘competition of outrage’ (p. 194). Antulio Echevarria also refers to Clausewitz to think about the nature of the ‘war on terror’. He makes a very interesting comment on the meaning of the trinity and the relative weight and configuration of its components: it is only after the fact, from a subjective standpoint, that we can determine which tendency, if any, exerted the predominant influence on the way a particular war was waged. At present globalization is ‘bringing the tendencies of purpose, hostility, and chance closer together, and making the effects of their interaction more immediate, less predictable, and potentially more influential’ (p. 209). For David Lonsdale the Revolution in Military Affairs (RMA) will be of no help. Friction and chance are in contrast in much of the RMA literature, which perceives war as an increasingly malleable phenomenon. Donald Rumsfeld succumbed to this illusion when planning the war in Iraq but the insurgency and terrorist campaigns painfully revealed the infinite possibilities and complex interactions of any war. The RMA literature often overlooks the existence and influence of an intelligent enemy, whereas Clausewitz always thought in terms of ‘reciprocal action’. The climate of war, so well described by Clausewitz, will not be altered by the information age. French Colonel Benoît Durieux adds interesting dimensions to the debate. He does not see ‘one single Clausewitzian theory, but several, elaborated at different periods in close conjunction with the prevalent political, strategic, and military context. This is completely consonant with Clausewitz’s original conception of his own work’ (p. 251-252). Durieux sees two temptations in contemporary strategic thinking: the first one characterizes the approach of the United States, especially their airpower theory and their RMA literature, and consists of using extreme, instantaneous violence in relative autonomy from the political context; the second one is present in Europe, especially in peacekeeping operations, and considers using limited violence for a longer time in complete continuity with the political environment. Clausewitz would reject the first temptation as politically counterproductive. ‘By inflicting immediate destruction, it denies the enemy any flexibility and deprives him of a political escape route’ (p. 261). This approach can simply accelerate escalation to the extremes of violence. As for the second temptation, Clausewitz would have dismissed it as he had done with the illusion of obtaining success without fighting a battle, through manoeuvre alone. In fact, the two temptations stem from a common desire to avoid violence in war and finally war itself, either by limiting the time violence is to be used, or by limiting the level of violence. ‘Not only are they both rarely effective in bringing about the desired political outcome, but they often result in the use of a higher overall amount of violence in the conflict’ (p. 263). We cannot miss without pain what Clausewitz told us. There must be a mix of control and independence between the three poles of the trinity, according to the situation. ‘The military commander must be, to a certain extent, free to decide which level of violence he needs to use, depending on the tactical situation in the field’ (p. 264). Clausewitz will not provide the solution for every war but he will remain a sure guide in avoiding most major failures in the use of military force in any circumstances.
Colonel Durieux has published his doctoral dissertation on Clausewitz’s reception in France. This is the synthesis expected by many on the subject. As early as 1814, Paris saw the first French translation of a Clausewitz’s work, which was also the only one signed during his lifetime: a study of the 1813 spring campaign. So the Prussian was not totally unknown along the Seine when the first extracts, quotations and commentaries of his major work, On War, appeared in the years 1830 and 1840. The first French translation of the whole treatise was made by a Belgian officer, Major Neuens, but published in Paris in 1849. Benoît Durieux has reviewed an enormous amount of French military literature of the 19th and 20th centuries. That enables him to resurrect a lot of forgotten writers and to stimulate further research. Before the Franco-Prussian war of 1870, Clausewitz was confusingly seen, in Belgium and in France, as having produced a major work. He raised questions and this could be viewed as promising beginnings. This initial reception was largely underrated by Raymond Aron. Clausewitz has become a subject of comment for sociologists, philosophers and anthropologists but military historians have a lot to add and this is a first major achievement of Durieux’s work. The second and most substantial part of it covers around 350 pages of a total of 769 (appendices, bibliography and index excluded). This part is devoted to the years 1870-1930, with Clausewitz and the ‘moral forces’ at the core of the military debate. The opening in 1877 of what would later be called the Ecole supérieure de Guerre was the preliminary step for the serious French study of Clausewitz. He was at first praised but also criticized by General Lewal, the apostle of an intellectual revival among the French military. Durieux characterizes the years 1884-1900 as ‘the first Clausewitzian age’. It was a time of uncertainty for French military policy. Clausewitz was then rediscovered and ‘imported’ as the common source of German military thinkers like Schlichting, Bernhardi or von der Goltz. He was also translated: On War for the second time, although not advantageously, by Lieutenant Colonel de Vatry, and a lot of historical writings as well (the texts on the campaigns of 1799, 1806, 1812, 1814 and 1815). Lucien Cardot was the catalyst of the rediscovery of Clausewitz in France. However he did not understand all of Clausewitz’s subtle distinctions and retained mainly the emphasis on moral forces and decisive battle. This is not new but Durieux shows that behind this usual distortion there was a real intellectual quest for a better understanding of many components of war (strategy and its differences with tactics, the principles of war, defence and attack) and that Clausewitz really helped the French military to think more about these. We are presented with a gallery of thinkers brilliantly sketched and about whom little was known before: Cardot, Gilbert, Dragomirov, Derrécagaix, Maillard, Bonnal, Grouard, Camon, Pierron. Foch is the most famous among this French school but he was not alone. As far as he is concerned, his reading of Clausewitz receives a new light: Durieux was able to consult Foch’s notebook, still held by his family. This reveals an in-depth reading of On War, on a scale unnoticed before. But it doesn’t mean that Foch was a disciple of Clausewitz, for he never presents himself as such, contrary to many German military writers. Clausewitz’s concepts helped Foch to establish his own and this was exactly what the Prussian had in mind. So many criticisms of Aron are misplaced, thinks Durieux who correctly reassesses the writings of Foch within their historical context.
The years 1901-1910 saw a decrease in Clausewitz’s influence, due to a less active military policy and a decline in patriotic fervour. A comeback characterized the years 1911-1914, linked to the rise of tensions in Europe. The French army saw the emergence of the doctrine of the offensive à outrance. In this ‘second Clausewitzian age’, the Prussian thinker was above all studied as the representative of the would-be enemy. Future General Jean Colin saw him as the founder of Prussian military doctrine, applied by Field-marshal von Moltke in 1870-1871. The Socialist leader Jean Jaurès devoted two chapters to Clausewitz in L’armée nouvelle (1911). On the eve of the Great War, the presence of Clausewitz was related to the moral mobilization of the Nation. From 1914 to 1930, military thinking in the French army was restricted by the government because of the war and its aftermath. With the peace began a critical assessment of the high command and of the war school. Colonel Gros Long made harsh accusations against Clausewitz’s influence in France. Only the brilliant but marginal Colonel Emile Mayer defended the value of Clausewitz’s ideas. But it was useless: they receded from the military teaching in the 1930s. If the advocate of the moral forces disappeared, a new Clausewitz began to emerge: the one of the link between war and politics. Philosophers would take the lead in this way but there were still military comments, like the interesting articles of General Lemoine. During World War II in London, a former Polish officer nicknamed Staro published books in French insisting on the famous sentence on war as a mere continuation of politics by other means. Raymond Aron, who was also in London at that time, probably became familiar with Clausewitz through Staro. But this didn’t save Clausewitz from appearing as a man of the past in post-1945 France. He progressively began a new comeback through his Marxist readers. He became one of the keys to understanding Lenin, Mao and revolutionary war. In 1955, a new translation of On War appeared, still commercialized today, by Denise Naville, with a preface by her husband Pierre, a well-known Trotskyist. General Lucien Poirier, later one of the leading theoreticians of French nuclear strategy, gave then some interesting views on Clausewitz, underlining a kind of French unease with him, the difficulty to understand him fully and the stimulating ambiguity of On War. Clausewitz suggested a method of analysis, he didn’t give prescriptions. Revolutionary war and nuclear strategy brought philosophers like Eric Weil to the work of Clausewitz because, contrary to most military writers, he invited thinking about war. For General Gallois, another founding father of the French nuclear doctrine, the ‘formula’ on the relationship between war and politics was reversed by the nuclear factor. This made the destruction of enemy’s forces no longer possible, due to the invulnerability of the retaliation capacity. Recourse to war thus became completely irrational. Clausewitz was discussed by General Beaufre and philosopher André Glucksmann in the 1960s but he was viewed as a man of the past. He was restored to life in 1976 with the two volumes of Raymond Aron, Penser la guerre, Clausewitz. On the whole, Benoît Durieux gives a very interesting history of the progressive familiarity of the French philosopher with the Prussian officer. He rightly situates Aron’s criticism at the level of theory for philosophers and sociologists. However essential historical and strategic aspects were neglected by Aron. His primary merit was to give Clausewitz a respectable place in French intellectual circles. The 1980s ended with a relative decline in the French interest for Clausewitz. The end of the Cold War brought him back to the forefront. Uncertainties in international relations since 1990 and the multiplication of civil and irregular wars incite a return to a Clausewitzian method enabling an understanding of the changing character of war. Following the vogue of Clausewitz in the US armed forces since the 1980s, the Prussian thinker is seen in the French army as a kind of bridge to the dominant ally and only surviving superpower. Although always suspected by some critics of being outdated, Clausewitz is also defended and treated as ‘the classic’ about war. The beginning of the 21st century sees in France as elsewhere a blossoming of new works about Clausewitz, including new translations. Durieux should have praised the contribution of Hervé Coutau-Bégarie and not only those of René Girard and General Vincent Desportes.
A final comment must be made about the approach chosen in this book. Durieux has been looking for everything published in French about and by Clausewitz. He therefore not only included Belgian or Swiss publications but also French translations of Ludendorff and Liddell Hart, as they had an impact on the French views on Clausewitz. This wide approach can be seen more accurately as ‘Clausewitz in French’ rather than ‘Clausewitz in France’. Although the reception of Clausewitz in Belgium is sometimes alluded to, it is not analyzed as such and should be treated in another work. On the other hand, Durieux doesn’t give a complete survey of Clausewitz in French military teaching. Of course he does give a lot about this but he didn’t delve through the archives systematically, even if one cannot be sure what such a research could have brought to light. But, whatever these shortcomings, the assessment of French readers of Clausewitz is almost exhaustive and the perspectives highlighted are very stimulating. No one is ever sure to have located all the quotations of a writer, even in a rather specialized field. But Durieux has succeeded in his task and he did it in a very clear and readable text, with a well-defined method and a modest and careful manner. If On War is a classic, Durieux’s work will be another one.
The last book this review article will present is from Peter Paret. Concluding the list of ‘new wave’ studies about Clausewitz with the co-translator of the criticized translation of On War is not intended to be ironic. Peter Paret is one of the greatest historians on the Napoleonic wars and on Clausewitz in particular. If his 1976 translation was influenced by the context of the Cold War and inspired by the will to be readable by the widest possible audience, every historian works within the conditions of his times and his works are just a milestone in a infinite quest for the truth. Peter Paret gave the Lees Knowles Lectures at Trinity College, Cambridge, during the fall of 2008. He expanded the text and published a small book, The Cognitive Challenge of War, Prussia 1806. The twin battles of Jena and Auerstaedt are quickly recounted. Paret then comments on some pictures and texts including poetry that reflect the new violence of war resented in Prussia. Clausewitz took over some of Schiller’s expressions to formulate his ideas. In developing a structural analysis of war he borrowed concepts from art, literature, and aesthetics of his time. ‘After a war, individuals generally analyze what has occurred and offer their interpretations. But it is rare for their ideas and formulations to transcend the immediate situation’ (p. 104). This was precisely the originality of Clausewitz. Paret goes on to contrast his experience of war with that of his rival in the theoretical writings on war: the Swiss Antoine-Henri Jomini. In 1793-1795 Clausewitz had seen much infantry combat on the company and battalion level. The diary of his regiment records a lot of military engagements. Clausewitz had seen more on combat than Jomini since his beginnings. Contrary to him and other military theoreticians, he also took war out of its military isolation and embedded it in society and politics. Life experience and a broad intellectual approach gave him an enduring advantage. Paret then notes that Clausewitz’s definitions are functional and not descriptive: ‘tactics constitute the theory of the use of armed forces in battle; strategy constitutes the theory of using battle for the purposes of the war’ (p. 114). This takes means and ends into account. It is applicable at all times and to every conceivable type of armed conflict, including terror campaigns. Clausewitz made a distinction commonly used at the time between three types of theory: utilitarian or prescriptive, pedagogic, and cognitive. The last one ‘aims to develop an analytic representation of war by nonutilitarian study, concerned solely with gaining a deeper understanding of the subject’ (p. 125). Rather than develop rules, cognitive theory depicts war, its elements and their way of functioning, as accurately as possible in a structural analysis, so as to help an independent mind to reach its own conclusions. When Clausewitz states in this way that defence is the stronger form of war, he does not propose that all wars should be fought defensively. ‘The interpreters of Clausewitz’s theories, writing on the eve of the First World War, not only reach firm conclusions where he develops options, they also follow styles of thinking and of writing that differ from his’ (p. 138). There were other wrong or biased readings after World War One and during the Cold War. This is the reason why there was a need for new interpretations and studies of this cognitive theory. The books analyzed above yield a much more accurate view on Clausewitz’s On War. What is remarkable is the convergence of views on the main topics: war as a mere continuation of ‘politics’ instead of ‘policy’, the many faces of war made possible by a wider range of combinations within the ‘wondrous trinity’, the danger of launching a war that by definition often escapes the control of policy, the mixture of Enlightenment and Romanticism in On War, its inclusion of a body of objective knowledge that may result in subjective use for a better understanding of every war.
 L. Bardiès and M. Motte, eds, De la guerre ? Clausewitz et la pensée stratégique contemporaine (Paris, 2008); R. Girard, Achever Clausewitz. Entretiens avec Benoît Chantre (Paris, 2007); S. Kinross, Clausewitz and America: Strategic Thought and Practice from Vietnam to Iraq (New York, 2007); J.T. Sumida, Decoding Clausewitz: A New Approach to On War (Lawrence, KS, 2008).
 C. von Clausewitz, On War, eds M. Howard and P. Paret (Princeton, 1976, 1984); R. Aron, Penser la guerre, Clausewitz, 2 vol. (Paris, 1976), transl. Clausewitz: Philosopher of War (London, 1983); M. Howard, Clausewitz (Oxford, 1983); P. Paret, Clausewitz and the State (Princeton, 1976, 1985).
 C. von Clausewitz, On War (1984), p. 89.
 A. Gat, The Origins of Military Thought. From the Enlightenment to Clausewitz (Oxford, 1989).
 M. Kaldor, New and Old Wars: Organized Violence in a Global Era (Stanford, CA, 1999); J. Keegan, A History of Warfare (New York, 1994); M. van Creveld, The Transformation of War (New York, 1991).
 W. Mulligan, ‘Total War’, War in History XV (2008); M. Broers, ‘The Concept of ‘Total War’ in the Revolutionary-Napoleonic Period’, War in History XV (2008).
 R. Girard, Achever Clausewitz.
 D. Queloz, De la manœuvre napoléonienne à l’offensive à outrance : la tactique générale de l’armée française 1871-1914 (Paris, 2009).
 A. Beyerchen, ‘Chance and Complexity in the Real World: Clausewitz on the Nonlinear Nature of War’, International Security XVII (1992-3).
 C. von Clausewitz, Schriften—Aufsätze—Studien—Briefe, ed. W. Hahlweg, 1+2 vol. (Göttingen, 1966, 1990). These volumes are fundamental for historians. They give a detailed survey of the archives relating to Clausewitz and his works.
 J.T. Sumida, ‘The Relationship of History and Theory in On War : The Clausewitzian Ideal and Its Implications’, Journal of Military History LXV (2001-2).
 Paret makes just one mistake regarding a uniform he identifies as one of a French chasseur à cheval on a painting by Caspar David Friedrich (p. 65). The helmet is absolutely impossible in 1812-1814. It belongs rather to the army of the kingdom of Wurttemberg and the yellow boots are pure fantasy.