Clausewitz and the First World War

Carl von Clausewitz’s On War — a book that belongs on any list of the great intellectual achievements of Western civilization — surveyed his subject theoretically and generally, based largely on relatively recent historical examples. Two periods of European warfare dominate his book: the revolutionary and Napoleonic wars, in which he had fought, and the wars of Frederick the Great from 1740 to 1761. Much of the greatness of the book arose from the profound difference in those two eras, a difference around which much of Clausewitz’s analysis revolves. Napoleon exemplified the practice of the first kind of war which Clausewitz described in his preface, one designed “to overthrow the enemy—to render him politically helpless or militarily impotent, thus forcing him to sign whatever peace we please.” Frederick the Great always sought the alternative objective: “merely to occupy some of his frontier-districts so that we can annex them or use them for bargaining at the peace negotiations.” Both Book Six on attack and Book Seven on defense include chapters aimed specifically at one or the other of these types of wars, and Book Eight, Chapter 9, it must always be kept in mind, refers specifically to plans for a war “designed to lead to the total defeat of the enemy.”[i] Nor is this all. Perhaps the most historical section of the book, in Book 8, Chapter 3, traces changes in the scale and methods of objectives of conflict across many centuries of European history.[ii] And Clausewitz repeatedly asked whether the massive wars of the Napoleonic era would become the model for future conflict — always wisely declining to give a particular answer.

Yet it is the fate of most great authors to be misunderstood, and despite, in my opinion, the relatively clear meaning of the text, a number of authors, most of them British, have portrayed Clausewitz as an advocate of a single form of war — all-out war aimed at the total annihilation and submission of the enemy — and, more specifically, blaming him, to some extent or other, for the course of the First World War. Basil Liddell Hart introduced this idea in The Ghost of Napoleon, Sir John Keegan did so with gusto in 1993 in A History of Warfare, and more recently Hew Strachan wrote, “Those who blamed Clausewitz for the slaughter of the First World War were not guilty of finding things in the text of On War that were not there.”[iii] Strachan’s comment has some foundation: German military leaders probably drew on Clausewitz at several key points in the war. Yet this essay aims to show that Clausewitz has far broader application to the First World War than that, that he could indeed have helped statesmen and generals make much wiser decisions at various points of the conflict, and that, in short, Lidell Hart and Keegan were certainly guilty of missing things in Clausewitz that were there.

One could write a very long book on the applicability of Clausewitz to the First World War, but I shall content myself with three points. First, the Schlieffen Plan certainly showed the influence of Clausewitz, and particularly that of Book 8, Chapter 9, to which I have already referred. But second, and more importantly, Clausewitz provided ample theoretical and practical foundation upon which to build much sounder objectives and strategies for the major powers in response to the initial stalemate on the Western Front. Lastly, I shall argue that another of Clausewitz’s concepts —his “remarkable trinity”— can best explain how the First World War came to an end. In short, while Clausewitz certainly did not cause the First World War, he might have enabled politicians and generals to fight it better, and that war revealed implications of his theories of which he, living in a different age, was unaware.

How did Clausewitz influence the war planning before 1914? Partly because none of the major powers possessed anything comparable to the United States’ National Security Council, many of their war plans did not match strategy to particular political objectives. Russia pledged itself to a rapid advance into Germany in order to help its ally France, without forecasting where that advance might stop or how it might end. Austro-Hungarian leaders seem to have failed to grasp that they would have inadequate forces to destroy Serbia unless Russia stayed out of the war until it was too late. The French Plan XVII did aim directly at France’s political objective, the recovery of Alsace-Lorraine. But the German general staff, acting without much political input, had under Schlieffen thought matters out more carefully. War against the Franco-Russian alliance required a quick, complete victory over one enemy or the other, and Schlieffen had chosen France. Reading On War, Book 8, Chapter 4, he would have noticed three recommended means of defeating an enemy: the destruction of its army, the occupation of its capital, and the delivery of an effective blow against a powerful ally. Leaving aside the third, he had written a plan to accomplish the first two objectives. The envelopment of the French Army by the advance through Belgium would destroy it and allow him to capture Paris far more quickly than the elder Moltke had in 1870-1. Schlieffen was dead by 1914, of course, and the younger Moltke had the extraordinary luck of fighting against a French war plan that could not have been better designed to help him had it been written in Berlin. However, he came a cropper. The Schlieffen plan sought a decisive battle deep in the interior of France — a strategy which, Clausewitz had warned, could indeed produce a victory with maximum political consequences, but which was also more difficult to achieve than a victory at the frontier. And so it was. The extraordinary advance of the German forces left them exhausted and undersupplied at the Battle of the Marne, and they had to retreat. Moltke had fallen into the trap Clausewitz described in Book 7, Chapter 5: he had passed the culminating point of the attack.

A stalemate, of course, had developed on the Western Front by the end of 1914. Clausewitz’s critics blame him for the decisions reached by the Germans and the allies to continue their search for total victory for the next four years, rather than to acknowledge new military realities and make peace. In so doing, they can refer to his characterization of wars aiming at the total destruction of the enemy as most closely approaching the “pure” form of warfare, or the “theoretical objective” of war. But as I have argued elsewhere, Clausewitz in those passages is simply arguing the ideal type of absolute war that he sets up as a straw man in Book 1, Chapter 1, to show that real war is different. In real war — and Clausewitz makes this point again and again — the destruction of the enemy’s forces is only one possible goal, and not always the best one, depending both upon the relative capabilities of one’s self and the enemy, the nature of the objective one seeks, and its cost.[iv] One could more fruitfully argue that Clausewitz, eighty years before the fact, told the leaders of the First World War exactly what they needed to hear, in words which many future generations would not be able to read without feeling a chill down their spine: “Since war is not an act of senseless passion but is controlled by the political object, the value of this object must determine the sacrifices made for it in magnitude and also in duration. Once the expenditure of effort exceeds the value of the political object, the object must be renounced and peace must follow.”[v]

Indeed, during the First World War many statesmen and some generals wrestled with the question of objectives, but nearly always, alas, without reaching an appropriate conclusion. German Chancellor Theobald von Bethmann Hollweg apparently realized by early 1915 that complete victory over all Germany’s enemies was most unlikely, and he hoped the moment would come when the Allies, the German General Staff, and the German people would be willing to make peace. Because however he was not willing in December 1916 to argue that Germany could not completely defeat France and Britain, he was helpless against the naval and military demands for unrestricted submarine warfare, since it alone seemed to offer the chance of total victory. War Minister Erich von Falkenhayn also doubted the chances of total victory and laid out the problems Germany faced well in December 1915, but opted for an offensive against Verdun rather than a peace offer.[vi] In January 1918 Prince Max of Baden wrote a memorandum for the Emperor, predicting that Ludendorff’s forthcoming offensive would fall short of victory and suggesting that Germany offer to withdraw from Belgium and France in return for peace within weeks of beginning the offensive. His advice was ignored, and Ludendorff pushed yet another German offensive far beyond the culminating point of his attack, wrecking his army.[vii] Various British leaders, even including Lloyd George, seem to have believed at critical moments in the war that complete victory might be impossible, but never dared try to persuade their colleagues or constituents that the time to call a halt had come.[viii] Unfortunately, both sides, for different reasons, expected total victory. The Germans had begun the war with striking successes, advanced steadily in the East, and knocked the Russians out of the war in early 1918. The Allies consoled themselves that their resources were increasing, especially after the United States entered the war in April 1917. By the time that General Ludendorff, the most powerful man in Germany, decided in early October 1918 that the time for compromise might have come, it was too late to get it from the Allies.

The termination of the First World War, indeed, can be most usefully analyzed from a Clausewitzian perspective – and specifically in light of one of his most misunderstood concepts – his remarkable trinity. Because of the widespread misunderstanding of this idea, we will do well to begin by quoting his own definition of the trinity of war in full.

“War is more than a true chameleon that slightly adapts its characteristics to the given case. As a total phenomenon its dominant characteristics always make war 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 it subject to reason alone.”[ix]

The elements of the trinity, then, are not the people, army and government, but rather, first, primordial violence, hatred and enmity; secondly, the play of chance and probability which occurs, as Clausewitz immediately makes clear, on the battlefield; and lastly, the policy objective for which the war was thought. Clausewitz immediately links these elements respectively with the people, the commander of the army, and the government, and adds, provocatively, that he seeks a theory that maintains a balance among these three elements, an objective which he unfortunately never followed up. Yet the concept of balance, I would suggest, explains the extraordinary manner in which the First World War finally came to an end: not as a result of straightforward battlefield victories, but because of revolutions and mutinies in one belligerent after another.

Although Clausewitz had seen the greatest European war to date first hand from 1812 until 1815, he had no idea how much larger, more expensive, and more destructive war might become in the next century. The First World War made unprecedented demands upon the people of the warring nations both on the battlefield and the home front. By the end of 1914 armies numbered in the millions and casualties already numbered in the hundreds of thousands, and several of the belligerents lost well over a million men killed by the end of the war. The economic mobilization the war required transformed the warring nations, and its financial demands wrecked the currencies of every warring continental nation. The Allied blockade reduced the food supplies among the Central Powers to dangerous levels. This effort was required by the third leg of the trinity, the policy objective, since every nation, as we have seen, was fighting for total victory. In order to persuade their people to make this effort, the governments involved had to arouse enormous passion, and they did so with the help of modern propaganda techniques. At one hundred years’ distance, the civilizations of Germany, France and Britain in the early twentieth century do not seem especially different from one another, but all these nations labeled their enemies as barbarians in the course of the war. And in fact, the passion which the governments aroused eventually became the enemy of rational policy. In March 1917, after the beginning of unrestricted submarine warfare had led to a break in diplomatic relations between the US and Germany, Count Bernstorff, the German Minister in Washington, returned to Berlin and told Bethmann Hollweg that peace could have been achieved with Wilson’s help had submarine warfare been held off for just four weeks. Bethmann replied that the German people would never have accepted peace without unleashing their submarines, since they believed they could be decisive in the war against Britain.[x]

To realize their policy objective of total victory and satiate the passion aroused among their peoples, the belligerent governments depended upon the second leg of the trinity, their military leadership on the battlefield. But such was the nature of military organization and technology in 1914-18 that the generals and admirals simply could not make the necessary decisive victory come to pass. Offensives could inflict (and incur) hundreds of thousands of casualties, and by 1918 the Germans had developed techniques enabling them to break through enemy lines and make substantial advances — but they could not exploit these victories to the extent of bringing about an enemy collapse. Clausewitz’s chapters on what battle could accomplish (Book 4) obviously reflected the scale and weaponry of military operations in his time, and he would surely have agreed that they must be revised when warfare, and therefore battle, changes. The inability of armies to win the victories demanded by the objectives of their governments and the passion of their people constituted an imbalance in Clausewitz’s trinity. Deprived of decisive victories, the passion of the people and of the soldiers at war had to find new outlets — and they did. One by one, they turned against their commanders and their governments. The history of the last two years of the First World War is a series of mutinies and revolutions, initially favoring the Central Powers but subsequently bringing themselves into chaos and leaving the Allies alone upon the battlefield.

In his greatest book, The Face of Battle, John Keegan pointed out the importance of mutiny in the First World War. “A point was reached in every army,” he wrote, “at which either a majority or a disabling minority refused to go on.”[xi] The key question, he might have added, was whether these mutinies were accompanied by political upheavals. By the end of 1916 the leadership of all the warring nations was speculating frequently about which would be the first to suffer internal collapse. Dissatisfaction with Tsarist leadership brought down the Russian government in March 1917, and that summer, the Kerensky government’s attempt at a new offensive led to the disintegration of the Army and, in November, to the Bolshevik Revolution and the end of Russia’s active participation in the war. The French survived such a mutiny in the spring of 1917, and the Italians survived the collapse of most of their army at Caporetto late that year. Keegan notes that an entire British army went to pieces under the weight of the Ludendorff offensive in March 1918, but they too managed to recover. Events among the armies and in the capitals of the Central Powers later that year proved decisive.

Beginning in September 1918, Bulgaria, Austria-Hungary, and Germany successively suffered the same catastrophic events: battlefield reverses, the collapse and desertion of whole units, revolution, and the fall of dynasties. The German case was of course the most interesting, because Ludendorff initially tried to head off the catastrophe by asking the Allies for a cease-fire in early October. When however weeks of negotiations showed that the Allies were not going to grant him an armistice that would later allow him to resume fighting, he changed his mind. Mutiny in the navy and army and revolution in the streets of Berlin, was followed by Ludendorff’s dismissal, the abdication of the Emperor, and the proclamation of the republic. The passion of the people had destroyed the armies and governments of the Central Powers, just as it had earlier in Russia, and left behind power vacuums which in turn led to new disasters over the next 30 years, and whose effects were felt nearly until the end of the twentieth century.

Social, political and technological changes had not made decisive victories and unlimited objectives impossible for all time by 1914-18. Both sides in the Second World War had equally sweeping objectives, but the Allies had the wherewithal actually to achieve them less than two years after they went on the offensive in 1943. As a result, the victorious governments, especially in Washington and Moscow, enjoyed unprecedented prestige and power at home and abroad for decades. Clausewitz spent little time on the danger of huge, indecisive conflicts like the First World War, because he had not experienced any. But On War, based as it is upon a firm grasp of war, human nature, and the effects of historical change, provides us with all the tools we need to understand what happened in the First World War — which in turn shows how difficult it is for human beings to rely mainly upon their rational faculties in the midst of the primordial violence, hatred and enmity so characteristic of a great war.