As so often happens, Clausewitz's disciples carried his teaching to an extreme which their master had not intended.... [Clausewitz's] theory of war was expounded in a way too abstract and involved for ordinary soldier-minds, essentially concrete, to follow the course of his argument – which often turned back from the direction in which it was apparently leading. Impressed yet befogged, they grasped at his vivid leading phrases, seeing only their surface meaning, and missing the deeper current of his thought.
Clausewitz was born on 1 June 1780 in Burg bei Magdeburg in the Prussian Duchy of Magdeburg as the fourth and youngest son of a middle-class family, though it made claims to noble status that Carl accepted. Clausewitz's family claimed descent from the Barons of Clausewitz in Upper Silesia, though scholars question the connection. His grandfather, the son of a Lutheran pastor, had been a professor of theology. Clausewitz's father, once a lieutenant in the Prussian army of Frederick II of Prussia (Frederick the Great), held a minor post in the Prussian internal-revenue Service. Clausewitz entered the Prussian military Service at the age of twelve as a Lance-Corporal, eventually attaining the rank of Major-General.
The end of the 20th century and the beginning of the 21st century have seen many instances of state armies attempting to suppress insurgencies, terrorism, and other forms of asymmetrical warfare. Clausewitz did not focus solely on wars between countries with well-defined armies. The era of the French Revolution and Napoleon was full of revolutions, rebellions, and violence by "non-state actors", such as the wars in the French Vendée and in Spain. Clausewitz wrote a series of “Lectures on Small War” and studied the rebellion in the Vendée (1793–1796) and the Tyrolean uprising of 1809. In his famous “Bekenntnisdenkschrift” of 1812, he called for a “Spanish war in Germany” and laid out a comprehensive guerrilla strategy to be waged against Napoleon. In On War he included a famous chapter on “The People in Arms.”
Clausewitz served during the Jena Campaign as aide-de-camp to Prince August. At the Battle of Jena-Auerstedt on 14 October 1806 – when Napoleon invaded Prussia and defeated the massed Prussian-Saxon army commanded by Karl Wilhelm Ferdinand, Duke of Brunswick – he was captured, one of the 25,000 prisoners taken that day as the Prussian army disintegrated. He was 26. Clausewitz was held prisoner with his Prince in France from 1807 to 1808. Returning to Prussia, he assisted in the reform of the Prussian army and state.
On 10 December 1810 he married the socially prominent Countess Marie von Brühl, whom he had first met in 1803. She was a member of the noble German von Brühl family originating in Thuringia. The couple moved in the highest circles, socializing with Berlin's political, literary and intellectual élite. Marie was well-educated and politically well-connected—she played an important role in her husband's career progress and intellectual evolution. She also edited, published, and introduced his collected works.
Opposed to Prussia's enforced alliance with Napoleon I, Clausewitz left the Prussian army and served in the Imperial Russian Army from 1812 to 1813 during the Russian Campaign, taking part in the Battle of Borodino (1812). Like many Prussian officers serving in Russia, he joined the Russian-German Legion in 1813. In the Service of the Russian Empire, Clausewitz helped negotiate the Convention of Tauroggen (1812), which prepared the way for the coalition of Prussia, Russia, and the United Kingdom that ultimately defeated Napoleon and his allies.
In 1815 the Russian-German Legion became integrated into the Prussian Army and Clausewitz re-entered Prussian Service as a colonel. He was soon appointed chief-of-staff of Johann von Thielmann's III Corps. In that capacity he served at the Battle of Ligny and the Battle of Wavre during the Waterloo Campaign in 1815. An army led personally by Napoleon defeated the Prussians at Ligny (south of Mont-Saint-Jean and the village of Waterloo) on 16 June 1815, but Napoleon's failure to destroy the Prussian forces led to his defeat a few days later at the Battle of Waterloo (18 June 1815), when the Prussian forces unexpectedly arrived on his right flank late in the afternoon to support the Anglo-Dutch-Belgian forces pressing his front. Clausewitz's unit fought at Wavre (18–19 June 1815), preventing large reinforcements from reaching Napoleon at Waterloo. After the war Clausewitz served as the Director of the Kriegsakademie, where he served until 1830. In that year he returned to duty with the army. Soon afterwards, the outbreak of several revolutions around Europe and a crisis in Poland appeared to presage another major European war. Clausewitz was appointed chief of staff of the only army Prussia was able to mobilize in this emergency, which was sent to the Polish border. Its commander, Gneisenau, died of cholera (August 1831), and Clausewitz took command of the Prussian army's efforts to construct a cordon sanitaire to contain the great cholera outbreak (the first time cholera had appeared in modern heartland Europe, causing a continent-wide panic). Clausewitz himself died of the same disease shortly afterwards, on 17 November 1831.
Clausewitz was a professional combat soldier who was involved in numerous military campaigns, but he is famous primarily as a military theorist interested in the examination of war, utilizing the campaigns of Frederick the Great and Napoleon as frames of reference for his work. He wrote a careful, systematic, philosophical examination of war in all its aspects. The result was his principal book, On War, a major work on the philosophy of war. It was unfinished when Clausewitz died and contains material written at different stages in his intellectual evolution, producing some significant contradictions between different sections. The sequence and precise character of that evolution is a source of much debate, as are exact meaning behind his seemingly contradictory claims (discussions pertinent to the tactical, operational and strategic levels of war are one example). Clausewitz constantly sought to revise the text, particularly between 1827 and his departure on his last field assignments, to include more material on "people's war" and forms of war other than high-intensity warfare between states, but relatively little of this material was included in the book. Soldiers before this time had written treatises on various military subjects, but none had undertaken a great philosophical examination of war on the scale of those written by Clausewitz and Leo Tolstoy, both of which were inspired by the events of the Napoleonic Era.
His widow edited, published, and wrote the introduction to his magnum opus on the philosophy of war in 1832. (He had started working on the text in 1816, but had not completed it.) She wrote the preface for On War and by 1835 had published most of his collected works. She died in January 1836.
Clausewitz's influence spread to British thinking as well, though at first more as a Historian and analyst than as a theorist. See for Example Wellington's extended essay discussing Clausewitz's study of the Campaign of 1815—Wellington's only serious written discussion of the battle, which was widely discussed in 19th-century Britain. Clausewitz's broader thinking came to the fore following Britain's military embarrassments in the Boer War (1899–1902). One Example of a heavy Clausewitzian influence in that era is Spenser Wilkinson, Journalist, the first Chichele Professor of Military History at Oxford University, and perhaps the most prominent military analyst in Britain from c. 1885 until well into the interwar period. Another is naval Historian Julian Corbett (1854–1922), whose work reflected a deep if idiosyncratic adherence to Clausewitz's concepts and frequently an emphasis on Clausewitz's ideas about 'limited war' and the inherent strengths of the defensive form of war. Corbett's practical strategic views were often in prominent public conflict with Wilkinson's – see, for Example, Wilkinson's article "Strategy at Sea," The Morning Post, 12 February 1912. Following the First World War, however, the influential British military commentator B. H. Liddell Hart in the 1920s erroneously attributed to him the doctrine of "total war" that during the First World War had been embraced by many European general staffs and emulated by the British. More recent scholars typically see that war as so confused in terms of political rationale that it in fact contradicts much of On War. One of the most influential British Clausewitzians today is Colin S. Gray; Historian Hew Strachan (like Wilkinson also the Chichele Professor of Military History at Oxford University, since 2001) has been an energetic proponent of the study of Clausewitz, but his own views on Clausewitz's ideas are somewhat ambivalent.
Clausewitz directly influenced Mao Zedong, who read On War in 1938 and organized a seminar on Clausewitz for the Party leadership in Yan'an. Thus the "Clausewitzian" content in many of Mao's writings is not merely a regurgitation of Lenin but reflects Mao's own in-depth study. The idea that war involves inherent "friction" that distorts, to a greater or lesser degree, all prior arrangements, has become Common currency in fields such as Business strategy and sport. The phrase fog of war derives from Clausewitz's stress on how confused warfare can seem while immersed within it. The term center of gravity, used in a military context derives from Clausewitz's usage, which he took from Newtonian Mechanics. In U.S. military doctrine, "center of gravity" refers to the basis of an opponent's power at the operational, strategic, or political level, though this is only one aspect of Clausewitz's use of the term.
Another Example of this confusion is the idea that Clausewitz was a proponent of total war as used in the Third Reich's propaganda in the 1940s. In fact, he never used the term "total war": rather, he discussed "absolute war" or "ideal war" as the purely logical result of the forces underlying a "pure," Platonic "ideal" of war. In what he called a "logical fantasy," war cannot be waged in a limited way: the rules of competition will force participants to use all means at their disposal to achieve victory. But in the real world, he said, such rigid logic is unrealistic and dangerous. As a practical matter, the military objectives in real war that support political objectives generally fall into two broad types: "war to achieve limited aims"; and war to "disarm" the enemy, "to render [him] politically helpless or militarily impotent." Thus the complete defeat of the enemy may not be necessary, desirable, or even possible.
With some interesting exceptions (e.g., John McAuley Palmer, Robert M. Johnston, Hoffman Nickerson), Clausewitz had little influence on American military thought before 1945 other than via British Writers, though Generals Eisenhower and Patton were avid readers. He did influence Karl Marx, Friedrich Engels, Vladimir Lenin, Leon Trotsky and Mao Zedong, and thus the Communist Soviet and Chinese traditions, as Lenin emphasized the inevitability of wars among capitalist states in the age of imperialism and presented the armed struggle of the working class as the only path toward the eventual elimination of war. Because Lenin was an admirer of Clausewitz and called him "one of the great military writers", his influence on the Red Army was immense. The Russian Historian A.N. Mertsalov commented that "It was an irony of fate that the view in the USSR was that it was Lenin who shaped the attitude towards Clausewitz, and that Lenin's dictum that war is a continuation of politics is taken from the work of this [allegedly] anti-humanist anti-revolutionary." The American Mathematician Anatol Rapoport wrote in 1968 that Clausewitz as interpreted by Lenin formed the basis of all Soviet military thinking since 1917, and quoted the remarks by Marshal V.D. Sokolovsky:
The deterrence strategy of the United States in the 1950s was closely inspired by President Dwight Eisenhower’s reading of Clausewitz as a young officer in the 1920s. Eisenhower was greatly impressed by Clausewitz’s Example of a theoretical, idealized “absolute war” in Vom Krieg as a way of demonstrating how absurd it would be to attempt such a strategy in practice. For Eisenhower, the age of nuclear weapons had made what was for Clausewitz in the early 19th century only a theoretical vision an all too real possibility in the mid-20th century. From Eisenhower’s viewpoint, the best deterrent to war was to show the world just how appalling and horrific a nuclear “absolute war” would be if it should ever occur, hence a series of much publicized nuclear tests in the Pacific, giving first priority in the defense budget to nuclear weapons and delivery systems over conventional weapons, and making repeated statements in public that the United States was able and willing at all times to use nuclear weapons. In this way through the Massive retaliation doctrine and the closely related foreign policy concept of Brinkmanship, Eisenhower hoped to hold out a creditable vision of Clausewitzian nuclear “absolute war” in order to deter the Soviet Union and/or China from ever risking a war or even conditions that might lead to a war with the United States.
After 1970, some theorists claimed that nuclear proliferation made Clausewitzian concepts obsolete after the 20th-century period in which they dominated the world. John E. Sheppard, Jr., argues that by developing nuclear weapons, state-based conventional armies simultaneously both perfected their original purpose, to destroy a mirror image of themselves, and made themselves obsolete. No two powers have used nuclear weapons against each other, instead using conventional means or proxy wars to settle disputes. If such a conflict did occur, presumably both combatants would be annihilated. Heavily influenced by the war in Vietnam and by antipathy to American strategist Henry Kissinger, the American Biologist, musician, and game-theorist Anatol Rapoport argued in 1968 that a Clausewitzian view of war was not only obsolete in the age of nuclear weapons, but also highly dangerous as it promoted a "zero-sum paradigm" to international relations and a "dissolution of rationality" amongst decision-makers.
Other notable Writers who have studied Clausewitz's texts and translated them into English are historians Peter Paret of the Institute for Advanced Study and Sir Michael Howard, and the Philosopher, musician, and game theorist Anatol Rapoport. Howard and Paret edited the most widely used edition of On War (Princeton University Press, 1976/1984) and have produced comparative studies of Clausewitz and other theorists, such as Tolstoy. Bernard Brodie's A Guide to the Reading of "On War", in the 1976 Princeton translation, expressed his interpretations of the Prussian's theories and provided students with an influential synopsis of this vital work.
Clausewitz's work is still studied today, demonstrating its continued relevance. More than sixteen major English-language books that focused specifically on his work were published between 2005 and 2014, whereas his 19th-century rival Jomini faded from influence. Historian Lynn Montross said the outcome, "may be explained by the fact that Jomini produced a system of war, Clausewitz a philosophy. The one has been outdated by new weapons, the other still influences the strategy behind those weapons." Jomini did not attempt to define war. Clausewitz did, providing (and dialectically comparing) a number of definitions. The first is his dialectical thesis: "War is thus an act of force to compel our enemy to do our will." The second, often treated as Clausewitz's 'bottom line,' is in fact merely his dialectical antithesis: "War is merely the continuation of policy by other means." The synthesis of his dialectical examination of the nature of war is his famous "trinity," saying that war is "a fascinating trinity—composed of primordial violence, hatred, and enmity, which are to be regarded as a blind natural force; the play of chance and probability, within which the creative spirit is free to roam; and its element of subordination, as an instrument of policy, which makes it subject to pure reason." Christopher Bassford says the best shorthand for Clausewitz's Trinity should be something like "violent emotion/chance/rational calculation." However, it is frequently presented as "people/army/government," a misunderstanding based on a later paragraph in the same chapter. This misrepresentation was popularized by U.S. Army Colonel Harry Summers' Vietnam-era interpretation, facilitated by weaknesses in the 1976 Howard/Paret translation.
Clausewitz used a dialectical method to construct his argument, leading to frequent misinterpretation of his ideas. British military theorist B. H. Liddell Hart contends that the enthusiastic acceptance by the Prussian military establishment – especially Moltke the Elder, a former student of his – of what they believed to be Clausewitz's ideas, and the subsequent widespread adoption of the Prussian military system worldwide, had a deleterious effect on military theory and practice, due to their egregious misinterpretation of his ideas:
Clausewitz's emphasis on the inherent superiority of the defense suggests that habitual aggressors are likely to end up as failures. The inherent superiority of the defense obviously does not mean that the defender will always win, however: there are other asymmetries to be considered. He was interested in cooperation between the regular army and militia or partisan forces, or citizen Soldiers, as one possible — sometimes the only — method of defense. In the circumstances of the Wars of the French Revolution and with Napoleon, which were energized by a rising spirit of nationalism, he emphasized the need for states to involve their entire populations in the conduct of war. This point is especially important, as these wars demonstrated that such energies could be of decisive importance and for a time led to a democratization of the armed forces much as universal suffrage democratized politics.
One prominent critic of Clausewitz is the Israeli military Historian Martin van Creveld. In his book The Transformation of War, Creveld argued that Clausewitz's famous "Trinity" of people, army, and government was an obsolete socio-political construct based on the state, which was rapidly passing from the scene as the key player in war, and that he (Creveld) had constructed a new "non-trinitarian" model for modern warfare. Creveld's work has had great influence. Daniel Moran replied, 'The most egregious misrepresentation of Clausewitz’s famous metaphor must be that of Martin van Creveld, who has declared Clausewitz to be an apostle of Trinitarian War, by which he means, incomprehensibly, a war of 'state against state and army against army,' from which the influence of the people is entirely excluded." Christopher Bassford went further, noting that one need only read the paragraph in which Clausewitz defined his Trinity to see "that the words 'people,' 'army,' and 'government' appear nowhere at all in the list of the Trinity’s components.... Creveld's and Keegan's assault on Clausewitz's Trinity is not only a classic 'blow into the air,' i.e., an assault on a position Clausewitz doesn't occupy. It is also a pointless attack on a concept that is quite useful in its own right. In any case, their failure to read the actual wording of the theory they so vociferously attack, and to grasp its deep relevance to the phenomena they describe, is hard to credit."
