Chapter 7

Clausewitz

[W]ar is not an exercise of the will directed at inanimate matter, as is the case with the mechanical arts, or at matter which is animate but passive and yielding, as is the case with the human mind and emotions in the fine arts. In war, the will is directed at an animate object that reacts.

—Clausewitz, On War

Carl von Clausewitz, born 1780, learned his military craft in the Prussian army as it failed to resist Napoleon’s mass army. Dismayed at Prussia’s craven subordination to victorious France, Clausewitz joined the Russian army (hence his appearance at Borodino) before returning to the Prussian army for the campaign that culminated at Waterloo and the final defeat of Bonaparte. Along with the bulk of the European officer class, he had been mesmerized by Napoleon. In 1812, he saw at close quarters the great man’s fallibility: his loss of the killer instinct at the critical moment, the limits to his genius. Clausewitz wrote a full account of the campaign, though his own role—and his account—was hampered by his lack of Russian. He did help organize the Convention of Tauroggen, whereby the Prussian contingent that had been obliged to march with Napoleon came to the Russian side.

Clausewitz did not think Borodino a classic of strategy. In the whole battle he found “not a single trace of an art or superior intelligence,” the result coming “less from a carefully considered decision than from indecision and circumstance.” His initial, and not unreasonable, conclusion was that the “vastness” of Russia made it impossible “to cover and occupy strategically.” A “large country of European civilization” could not “be conquered without the help of internal discord.”¹ Later he was harsher on Napoleon for not chasing the Russian army and described Borodino as a battle that was “never completely fought out.”² Both judgments had important implications: the first that the degree of popular support for the state made a difference when dealing with external threats; the second that a victory that did not leave the enemy fatally wounded was of limited value.

Clausewitz’s military reputation in Prussia was modest, and when he was sent to direct the war school it was in an administrative capacity. He did not teach, but he did have the time to collect his thoughts about this remarkable and transformational period of warfare and pull them together for a master- work, On War.

War’s tendency toward the absolute both thrilled and appalled the younger Clausewitz. The more mature Clausewitz appreciated the reasons why wars in practice still fell short of the absolute and that, post-Napoleon just as pre-Napoleon, they might be fought for more modest ends than the survival of states. It was this that led to his determination to engage in a major revision of his whole text, a project that was only partly completed when he died. According to one interpretation, this moment of truth came upon Clausewitz gradually; by another view, 1827 was more of a crisis as he realized that his theory of war failed to account sufficiently for the various forms in which it had actually occurred.³ He was still in the process of revising On War when he was struck down by cholera in 1832. His widow did the best she could with the book’s posthumous publication, but the final version inevitably left commentators guessing about what might have been found had he lived to complete the work to his satisfaction.

Jomini

While Clausewitz was seeking to advise the Russians in 1812, Jomini was on the French side. In the retreat from Moscow, he lost his papers at a river crossing as the remnants of the French army were harassed by Russian partisans. Although Clausewitz is now considered to be the greater of the two and Jomini is rarely read, it was Jomini who for most of the nineteenth century was taken to be the foremost interpreter of the Napoleonic method. Napoleon was said to have remarked that Jomini betrayed the innermost secrets of his strategy. Jomini certainly claimed, based on his observations of the master, to have discerned basic principles of warfare. This earned him the “dubious title of founder of modern strategy.”⁴

Jomini was born in Switzerland in 1779. Though he started work as a banker in Paris, he joined the French army in 1797 and came under the patronage of then General and eventually Marshal Michel Ney. Jomini wrote a treatise on the campaigns of Frederick the Great in 1803. This work contained those core beliefs which sustained him until his death in 1869 at the age of 90. He held staff positions for both Napoleon and Ney, but was a difficult egotist and a serial resigner. By 1813 he had risen to become Ney’s chief of staff, but after he was denied promotion to general de division he offered his services to Russia, where he became a full general. His core ideas were published in his Art of War (always a popular title), which was first published in 1830 and then in a revised form in 1838.⁵ His book has been described as “the greatest military textbook of the nineteenth century.”⁶ By elucidating the enduring principles of strategy, Jomini sought to “make instruction easier, operational judgment sounder, and mistakes less frequent.” The Art of War was published widely. This meant that opposing armies might well have been following the same precepts, and so the advice would become self-neutralizing, unless one side dared to seek advantage by breaking Jomini’s rules.

To Jomini, strategy was the sphere of activity between the political, where decisions were made about who to fight, and the tactical, which was the sphere of actual combat. By saying that strategy was the art of making war upon the map, he was interested in how the theater of operations as a whole was conceived by the commander and the moves against the enemy formulated, while taking advantage of the spatial awareness made possible by modern cartography. “Strategy decides where to act; logistics brings the troops to this point; grand tactics decides the manner of execution and the employment of the troops.”⁷

Politics and tactics were governed by different principles, and Jomini had surprisingly little to say about either. According to John Shy, the only aspect of war that “truly interested him concerned the supreme commander, the Frederick or Napoleon who played the great bloody game, who by sheer intellect and will dominated the men who served him and used them to defeat his enemies.” Jomini’s armies appeared as “faceless masses, armed and fed in mysterious ways.” Their commanders would show their greatness by massing force against weaker enemy forces at some decisive point.⁸ Both Frederick the Great and Napoleon had demonstrated the importance of following this core principle, though it was by no means straightforward in application. Focusing on one point to the exclusion of others, and leaving your own flanks vulnerable, required a degree of boldness and an ability to weigh risks. Ways had to be found to mass the army for the attack and to identify the main point against which to direct the attack.

Jomini failed to test the historical cases which did not conform to his precepts. He also assumed that military units of equivalent size were essentially equal in how they were armed, trained, disciplined, supplied, and motivated. Strategy was therefore important because only the quality of the commanders and their decisions really made a difference. This was why he could conceive of it as following timeless principles, which required him to assert during his long life that major material shifts, such as the use of railways, were matters of detail. If the principles really were timeless, why was Napoleon such a revelation? Jomini’s answer was that the growing maturity in military thought meant that the principles were properly appreciated.⁹ He was not the last to use this argument.

Before Jomini went out of fashion during the twentieth century he was the first port of call for any aspiring strategist and a model of lucidity and intelligibility. Jomini might not always have been a scintillating read, but he was much easier to follow than Clausewitz.

The relationship between the two was complex. The younger Clausewitz clearly borrowed from Jomini, and the second edition of the Art of War took into account Clausewitz’s criticisms.¹⁰ The two men never met and did not speak warmly of each other. On many operational issues, the differences were not great. Jomini claimed to be aware of the dangers of theoretical pedantry, while Clausewitz grasped the importance of operational techniques. Jomini’s prime purpose was instruction and he found Clausewitz’s theorizing overblown. As Clausewitz developed his ideas, he differentiated himself from von Bulow’s mathematical approach, but his criticisms might also be taken to apply to Jomini. He observed that efforts to “equip the conduct of war with principles, rules, or even systems” failed because they could not “take an adequate account of the endless complexities involved.” “Pity the soldier,” wrote Clausewitz, “who is supposed to crawl among these scraps of rules, not good enough for genius, which genius can ignore, or laugh at. No; what genius does is the best rule, and theory can do no better than show how and why this should be the case.”¹¹ Clausewitz came to be celebrated as a greater theorist of war, but Jomini had enduring appeal to military planners. Because he developed his theories while Napoleon was at his peak, Jomini’s writing showed an optimism that is lacking in Clausewitz. Hew Strachan notes how Jomini’s confidence in his principles, his “rational and managerial,” “prospective and purposeful” theory of war and self-contained view of battle appealed to generations of American generals and admirals.¹²

Clausewitz’s Strategy

In On War, Clausewitz was attempting something very ambitious. More than a textbook for an aspiring general, this was a whole theory of war. His achievement was to develop a conceptual framework that captured war’s essence sufficiently for subsequent generations to return to it when seeking to make sense of the conflicts of their own time. The ambiguities and tensions in On War allowed Marxists, Nazis, and liberals to claim it as authoritative support for their own theories and strategies.¹³ Even those who considered On War wrongheaded and out of date entered into direct competition, as if their own credibility depended on undermining Clausewitz.¹⁴ Contributing to the advanced scholarship on Clausewitz now requires discussing the adequacy of the available translations, the interaction of biography and intellectual development, what might be read into occasional phrases that are suggestive of larger thoughts, and the dual meanings carried by key concepts and their application in particular cases.¹⁵

With this in mind, we can explore the theory of strategy that emerged from Clausewitz’s theory of war. Clausewitz’s most famous dictum, that war is a continuation of policy by other means, is a charter for strategists. The choice of the word policy in the translation by Michael Howard and Peter Paret reflected their view that the reference needed to be something above everyday “politics,” a word which they saw as having negative connotations in Britain and the United States. Bassford has argued that policy sounds too settled, unilateral, and rational, while politics has the virtue of conveying interactivity, binding rivals together in their conflict.¹⁶ Both meanings can be made to work. The key point is that insisting on political purpose takes war away from mindless violence. This dictum does not propose that war is always a sensible expression of policy, or that the movement from politics to war is from one defined state to another. The difference lies in the violence and the sharpness of the confrontation between two opposed wills. This in turn exacerbates the influence of those factors of emotion and chance that are evident in the political sphere but become so much more significant in the military, and constantly complicate war’s conduct. So while Clausewitz by no means rules out an effective strategy, for this would render On War a pointless exercise, his stress was on the limits to strategy, the constraints that make it unwise to try to be too clever.

The challenge for politics, and therefore strategy, was to impose a semblance of rationality, in terms of the dogged pursuit of state objectives. Although his dictum came to be regularly cited as an authority for civilian primacy over the military, Antulio Echevarria cautions that many of Clausewitz’s thoughts on politics and international conflict, especially in the unrevised sections, were circular and deterministic. The key to Clausewitz’s greatness as theorist of war lay instead in the observation that was at the heart of his mature thought, that war was shaped by a remarkable trinity—composed of primordial violence, hatred, and enmity, which are to be regarded as a blind natural force; of the play of chance and probability within which the creative spirit is free to roam; and of its element of subordination, as an instrument of policy, which makes [war] subject to reason alone.¹⁷

His theory depended on the dynamic interplay of these three factors. The trinity superseded the dictum, for it suggested that politics was not in command but one factor among three. With respect to the survival of the state in a challenging international system—which was how Clausewitz understood the concept—politics must always set the terms for war, but politics could not challenge the “grammar of war” lest it reduce the chances of success and so the achievement of the ultimate objective. This could in turn lead to military actions with great political consequences. Despite the apparent subordination of the military to politics, the dynamic quality of the trinity helped explained why the relationship was not so simple.¹⁸

As a clash of opposing wills, a duel on a grand scale, war in the ideal sense tended to absolute violence. Having posed this possibility, Clausewitz pointed to the other two parts of the trinity to explain why it was unlikely to be realized. Politics was one source of restraint, but friction was another. This was one of Clausewitz’s most significant contributions to military thought. Friction helped explain the difference between war as it might be—that is, absolute and unrestrained—and actual war. He explained the phenomenon in one of his most celebrated passages:

Everything in war is simple, but the simplest thing is difficult. The difficulties accumulate and end by producing a kind of friction that is inconceivable unless one has experienced war . . . Countless minor incidents—the kind you can never really foresee—combine to lower the general level of performance, so that one always falls short of the intended goal.

The result was “effects that cannot be measured, just because they are largely due to chance.” Friction thus caused delay and confusion. Action in war became like walking in water, and vision was regularly obscured. “All actions take place in something virtually akin to dusk, which in addition, like fog or moonlight, gives objects an exaggerated size and a grotesque view.”¹⁹

Generals in charge of military organizations were doomed to disappointment. Everything would take longer than it should, and it would be hard to generate the flexibility needed to keep up with events.

Within the paradoxical trinity, violence and chance could still be subordinated to politics and the application of reason. If the strategist did not apply reason, war would become progressively chaotic and unpredictable. The challenge for the intelligent strategist was to anticipate both the enemy and all those elements of friction and chance that got in the way. The correct approach was not to give up and assume that chaos and unpredictability would mock all plans and overwhelm best efforts but rather to prepare for such eventualities in advance. The test of a great general was making a plan that he could see through. Clausewitz wrote about the need for the commander to be a military genius, but he did not necessarily mean an exceptional, once-in-a-generation individual such as Napoleon. Genius required a grasp of the demands of war, the nature of the enemy, and the need to stay cool at all times. Indeed, Clausewitz was wary of the general who tried to be too smart. He preferred those who kept their imaginations in check and a firm grip on the harsh realities of battle.

So while his description of war suggested that the wise course would be to retain maximum flexibility and prepare to seize opportunities as they arose, he came to the opposite conclusion, arguing for a clear plan of conduct based on a series of connected, sequential steps. He preferred a stress on careful planning without distractions. The strategist must “draft the plan of the war, and the aim will determine the series of actions intended to achieve it.”²⁰ A war should not be started without a plan for its conduct firmly in mind. Once implementation had begun, it should only be amended at times of unavoidable necessity.²¹ Clausewitz’s definition of strategy as “the use of the engagement to achieve the objectives of the war” translated political goals into a military aim. The strategist would “shape the individual campaigns and, within these, decide on the individual engagements.”²² Preferring to enter war with a plan for victory was understandable. But why the confidence that any plan could be implemented?

Clausewitz offered three reasons. First, despite all the talk of unpredictability, not everything was a mystery. Certain actions had known effects. An enemy attacked from behind or caught in an ambush would exhibit lower morale and less bravery. Most importantly, it was possible to make relatively objective assessments of the opposing sides, taking into account their experience and their “spirit and temper.” While the enemy’s own plans and responses to situations could not be known exactly, the laws of probability could be applied. Confronting an excitable visionary would require a different plan than that for an enemy known to be hard and calculating. The bold would be granted more respect than the cautious, the active more than the passive, and the clever more than the stupid.

A second factor was the unreliability of intelligence. Without a robust starting plan, occasional reports might cause an undue deviation: “Many intelligence reports in war are contradictory; even more are false, and most are uncertain.” Furthermore, intelligence tended to have a pessimistic bias. The exaggeration of bad news led to gloomy and despondent commanders who conjured up landscapes of imagined perils: “War has a way of masking the stage with scenery crudely daubed with fearsome apparitions.” These vivid impressions overwhelmed systematic thought, and so “even the man who planned the operation and now sees it being carried out may well lose confidence in his earlier judgment.” He must therefore exorcise false appearances by trusting instead in “the laws of probability” and in his own judgment gained from “knowledge of men and affairs and from common sense.”²³ With improved information gathering, Clausewitz’s advice to ignore timely intelligence now appears as more of a recipe for disaster than a means of avoiding unnecessary panic.

Third, both sides were subject to friction, so it was a poor excuse for defeat. The question was who could cope with it better. The essence of good generalship was to triumph over friction, to the extent possible, through both careful planning and maintaining a presence of mind when the unexpected happened.²⁴ “The good general must know friction in order to overcome it whenever possible, and in order not to expect a standard of achievement in his operations which this very friction makes impossible.”²⁵ This important qualification warned against excessive strategic ambition.

So size mattered. Armies were “so much alike” that there was “little difference between the best and the worst of them.” The most reliable means to success, in both tactics and strategy, was therefore superiority in numbers: “The skill of the greatest commanders may be counterbalanced by a two-to-one ratio in the fighting forces.” Clausewitz could see the attraction of cunning, indirect strategies, which could confuse the enemy and lower morale. He noted that it might be thought that “strategy” took its name from “trickery,” but he saw little historical evidence that tricks (stratagems) could be effective and considered it dangerous to make a false impression by deploying large forces, which might be left in the wrong position when they were really needed. At the tactical level, surprise was important and attainable, but at the strategic level the mobilization and movement of forces were likely to give the game away. Friction was also a major factor, holding up the sort of movements necessary to catch the enemy unawares. So when it came to the choice of force or guile, Clausewitz opted for the former. The “strategist’s chessmen do not have the kind of mobility that is essential for stratagem and cunning . . . accurate and penetrating understanding is a more useful and essential asset for the commander than any gift for cunning.” His advice was to keep the plan simple, especially against a capable opponent. A simple plan would require the excellent execution of each engagement; for this reason, tactical success was vital. In this respect, the strategic plan survived so long as successive engagements were being won.

This put a premium on knowing when to stop. An enemy willing and able to redouble his efforts put a final victory out of reach. Another important Clausewitzian concept was the “culminating point of victory,” the point at which further attack could lead to a reversal of fortunes. It was “important to calculate this point correctly when planning the campaign.”²⁶ This was about the developing balance of advantage as a campaign progressed. After being wounded, would the enemy collapse with exhaustion or be enraged? What were the distractions to be avoided, the opportunistic but diverting targets away from the main line of advance? There would be temptations to capture “certain geographical points” or seize “undefended provinces,” as if they had value in themselves as “windfall profits,” but that could put the main aim at risk. A consistent, focused approach should discourage disruption. Here were the reasons for Napoleon’s failure in 1812.

The Russian campaign and lack of confidence in strategies based on surprise and complex maneuvers led Clausewitz to the view that the advantage lay with the defense. The forward movement necessary to occupy enemy territory taxed the attacker’s energies and resources, while the defender was able to use this time to prepare to receive the attacker. “Time which is allowed to pass unused accumulates to the credit of the defender.” Surprise could work as much in favor of the defense as the offense. It was about catching the enemy unawares with regard to “plans and dispositions, especially those concerning the distribution of forces.” The attacker was “free to strike at any point along the whole line of defense, and in full force,” but could still be surprised if the defender was stronger than expected at the spot chosen. The defender operated on familiar ground, could choose his position carefully, and enjoyed short supply lines and a friendly local population, which could be a source of intelligence and even reserves. Even if the offensive succeeded, the occupying force might be ground down through insurrectionary or partisan warfare, as Napoleon discovered in Spain. Moreover, so long as the defending state could avoid surrender, other states might join in on its side. According to prevailing notions of the “balance of power,” other states were likely to intervene against a determined aggressor in order to prevent it becoming too powerful. Even the strongest individual state could be defeated by an organized coalition ranged against it and determined to restore equilibrium to the international system. This too Napoleon discovered to his cost. But while Clausewitz described defense as the stronger form of fighting, he also noted that its purpose was negative. It was limited, passive, concerned only with preservation. Only attack could secure the objectives of war. Defense was unavoidably preferred by the weak, but once there was a favorable balance of strength, the incentives were to move to the attack. “A sudden powerful transition to the offensive—the flashing sword of vengeance—is the greatest moment for the defense.”²⁷

When it came to the offense, another important Clausewitzian concept was the “center of gravity” (Schwerpunkt). Along with a number of his other concepts, including friction, this was taken from the physics of the day. A center of gravity represented the point where the forces of gravity could be said to converge within an object, the spot at which the object’s weight was balanced in all directions. Striking at or otherwise upsetting the center of gravity could cause objects to lose balance and fall to the ground. For a simple, symmetrical shape, finding the center of gravity was straightforward. Once an object had moving parts or changes in composition, the center would be constantly shifting. Clausewitz never quite got to grips with the metaphor. “A center of gravity,” he explained, “is always found where the mass is concentrated the most densely. It presents the most effective target for a blow; furthermore, the heaviest blow is that struck by the center of gravity.” The Schwerpunkt was “the central feature of the enemy’s power” and therefore “the point against which all our energies should be directed.” This required tracing back the “ultimate substance” of enemy strength to its source and then directing the attack against this source. The target might not be a concentration of physical strength but possibly the point where enemy forces connected and were given direction. Any disruption would maximize effects beyond the immediate point to the larger whole.

Though he did not fully follow this through, Clausewitz recognized that the critical point might be a capital city or the coherence of an alliance. With respect to alliances, which had been central to the ebb and flow of the Napoleonic Wars, Clausewitz understood that individual members would always have their own interests at the fore and that joining an alliance could carry risks (for example, by attracting force away from a partner or by having to aid a much weaker partner). If the alliance was to prosper, it needed a unity of political purpose or at least “the interests and forces of most of the allies” must be “subordinate to those of the leader.” This offered a center of gravity that an opponent could challenge, disrupting the alliance by encouraging disunity.²⁸ Not all peacetime alliances even turned into a joint enterprise against a common foe, as the matter became akin to a “business deal” and actions were “clogged with diplomatic reservations.”²⁹

From this it can be seen that the identity of a center of gravity was not obvious. The concept only made any sense if it was assumed that the enemy could be viewed holistically, as a unity, so that an attack on the point where it came together could throw it off balance or cause collapse. But there might be no obvious single focal point, if the enemy did not present itself in that way. On this basis, a loose coalition might be harder to disrupt than a tight alliance, although it might fight less effectively for the same reason.³⁰ If the enemy was not totally committed—for example, in a limited war—there might be even less reason to expect that a blow against its army would have an impact much beyond the area in which it was committed. Yet it was this concept, as much as any other of Clausewitz’s, that came to be embedded in Western military thought, although often as a source of confusion rather than clarity.

The Sources of Victory

As Clausewitz described the nature of war, strategy became a sustained act of will, required in order to master its terrible uncertainties and resulting from human frailties and the capricious impact of chance. Since the enemy faced the same problems, it was still possible to prevail by bringing superior force to bear against the enemy’s center of gravity. Clausewitz was of the view, almost taken for granted in his time, that once the enemy army was defeated in battle, the route to victory was clear. Without an army a state was helpless. It could either be eliminated, gobbled up in its entirety, or forced to accept whatever terms the victor might impose. Because of this, states would do everything possible to avoid defeat and carry on the fight in some way. In the new post-1789 era, this was as much a matter of popular enthusiasm as governmental judgment.

Clausewitz understood how policy linked the statesman and the general: policy gave the general his objectives and the resources available to meet them. As for these objectives, Strachan refers to a creed of 1815, “For me the chief rules of politics [or policy] are: never be helpless; expect nothing from the generosity of another; do not give up an objective before it becomes impossible; hold sacred the honor of the state.”³¹ In giving direction to strategy, therefore, policy was essentially an expression of national interests in relations with other states. Clausewitz acknowledged, but did not really explore, the impact of the internal politics of the state on strategy, as a particular form of friction. It was important that the commander-in-chief be part of government, in order to be able to explain the strategy being followed and help assess its relationship with policy. Clausewitz could not but be aware of how strong, popular national feelings created their own pressures for war and a determination to fight to the bitter end. It was, however, largely through a growing sense of the limits of what could be achieved through war that he began to consider the possibility of war pursued for limited ends, as it had been in the eighteenth century.

Though a state that had lost its army was effectively beaten, “victory consists not only in the occupation of the battlefield, but in the destruction of the enemy’s physical and psychic forces, which is usually not attained until the enemy is pursued after a victorious battle.”³² If enemy armed forces were destroyed, whatever was wanted from the enemy could be seized and its public opinion would be cowed. Yet, as at Borodino, total destruction of the enemy army might not be possible. Even if achieved, the result might only be temporary. A defeated enemy might rise again. It would harbor thoughts of revenge, of reversing the setback. As victory might be temporary rather than durable in its effects, it might be prudent to negotiate a settlement under the most favorable terms when the optimum position has been reached.

Napoleon’s career warned of the consequences of relying on military victory as the sole means of achieving political objectives. He wanted complete hegemony in Europe. There was a notion, still to be found among some international relations theorists, that this was an entirely natural goal for a great power. In practice, because victory could never be complete, it was a recipe for continuing war and eventually a friendless defeat. Napoleon’s stunning victories over the Austrians and Russians in 1805, and then the Prussians the next year, did not take them out of the picture. Having supinely accepted the result of battle, they re-entered the fight, this time understanding France’s methods better. As Napoleon discovered, the obvious counters to a regular army seeking a decisive battle were guerrilla warfare or reconstituted armies combining in a formidable coalition to ensure numerical superiority. He had relied on battle to achieve his objectives but did not have a clear notion of how these objectives could result in a new European political order with any sort of stability. It was hard to dominate the continent on the basis of methods that others could copy. Undoubtedly a genius in battle, Napoleon lacked political subtlety. He inclined toward punitive peace terms and was poor at forging coalitions.

If the aim of war was a favorable peace, then military operations were a means to this end. War that was “a complete untrammeled, absolute manifestation of violence (as the pure concept would require)” would “usurp the place of policy the moment policy had brought it into being.” Policy would be driven away and war would rule by its own laws “very much like a mine that can explode only in the manner or direction predetermined by the setting.”³³ In accepting that war could be fought for limited objectives and was not inevitably absolute in means or ends, there were still perplexing problems. The more ambitious the objectives, the more a state would commit to war and the more violent it would become. But the corollary could not be guaranteed. A war begun with limited objectives might not be fought by correspondingly limited means. Combat might be infused with the purposes of war but was shaped by armies in opposition. This created a reciprocal effect that could generate explosive forces from within, whatever the attempts to establish controls from without. We now tend to call this process “escalation.” Popular engagement could aggravate the effect. “Between two peoples and states such tensions, such a mass of hostile feeling, may exist,” Clausewitz observed, “that the slightest quarrel can produce a wholly disproportionate effect—a real explosion.”³⁴

In this tension we find the clue to Clausewitz’s enduring influence. He understood that rational policy could impose itself on war, but it was always competing with the blind natural forces of “violence, hatred and enmity,” as well as probability and chance. He linked policy, chance, and hatred to government, the army, and the people, respectively, although the link perhaps gave a restrictive, institutional form to these attributes. Each state had its own trinity, in tension within itself as well as with that of the opposing side. “Where policy is pitted against passion, where hostility ousts rationality, the characteristics of war itself can subordinate and usurp those of the ‘trinity.’ ”³⁵ This broader political context underlined the basic point. Clausewitz accepted that the military task should be set by the politicians. Once that had been accomplished, the military could expect the politicians to use a military victory to best advantage. At the time, the normal assumption was that a political victory would naturally follow a military victory. If the assumption was wrong, then strategy’s focus on military affairs was insufficient. It was about the clash of opposing forces when the real issue concerned the clash of opposing states.

The Roman origins of the word victory located it firmly in the military sphere. Jomini and Clausewitz understood that the objective of war came from outside the military sphere. Their basic instinct, however, was that with the “retirement of the enemy from the field of battle,” terms could be imposed. There was some proportion between ends and means. But the problem remained that while a military victory was measurable, a political victory was not necessarily so. The forms of resistance and disaffection a defeated people might show could soon compromise the apparent achievements on the battlefield. If the broader political consequences of war were difficult to anticipate, then the military was likely to be left exploring its own tangible goals without regard to the broader context. Moreover, as Napoleon’s career demonstrated, simply taking the same approach to military strategy in a series of repeat performances was unlikely to sustain a high level of results. Opponents would see the pattern and work out the counters. Brian Bond noted how this raised a fundamental problem: “If strategy was a science whose principles could be learnt what was to prevent all the belligerents learning them? In that case stalemate or attrition must result.”³⁶