War has a changing and unchanging nature--a dual nature. The classical theorists, in accordance with their own historical and cultural contexts, were attempting to lay bare war’s timeless, unchanging nature. These aspects of the classical theories continue to apply to warfare today and into the future because they are based on dimensions of human political nature.
* * *
Do the classical theorists still apply to modern warfare in the twentieth century? What about in the twenty-first century? Before all else there is the rather obvious observation as to the long-enduring relevance of the classical theorists to military art and doctrine, and to the practice of strategy. Mao borrowed extensively from Sun Tzu, and Jomini and Clausewitz have thoroughly shaped twentieth century U.S. Army doctrine, which has in turn influenced military doctrine from Canada to Australia. Although Jomini’s writings were widely influential in shaping U.S. Army tactical doctrine, “Clausewitz’s theories represent the foundation of U.S. military doctrine.” Clausewitz’s work--and the works of Sun Tzu, Thucydides, and Machiavelli--still offers sound advice to political leaders and practitioners of war, especially at the strategic level, borne of extensive real-world experience of war and historical study, improved at least somewhat, in the case of Clausewitz, by the application of German philosophical methods. This perceived relevance to current affairs has generated a steady stream of writings about the consequences of heeding or not heeding the advice of the classical theorists, but especially of Sun Tzu and Clausewitz.
The classical theorists still apply to modern warfare, but with some interpretation to account for different historical periods, obviously, especially with respect to technology. The effects of the industrial revolution in Europe had not yet altered life much in Clausewitz’s lifetime and therefore, not too surprisingly, he did not seriously consider the impact of technology on the art and practice of war. Classical theories to remain valuable, of course, need to be updated and reinterpreted for current realities. Clausewitz’s theory of a remarkable trinity is not the same today as it was in his day. He understood that war is composed of the blind natural force of the people, the creative realm of the commander, and the rational subordination of these factors to reason as an instrument of policy by a government, but his thinking would need to adjust to different forms of political leadership today--forms that qualify as non-state. Clausewitz acknowledged that social, political, cultural, technological, and economic forces will change the form of warfare in different historical periods, but that the change would adjust the balance of elements in the remarkable trinity, not that the nature of war itself will change. In the two hundred years since the wars of Napoleon this thesis has remained valid.
Sun Tzu and other classical theorists compiled important insights that do not prescribe specific actions in battle and in war but nonetheless add to the practitioners total understanding of war. For example, Sun Tzu wrote that the most important thing to do in war is to attack the enemy’s strategy, then divide his alliances, and then attack his army. In another example, Sun Tzu described five fundamental factors which he believed were essential to contemplating war: moral influence, weather, terrain, command, and discipline. While some might find these short passages sophomoric or even trite, when combined with a broad understanding of military history and leadership, especially when reinforced with military experience, aphoristic statements can provide a useful professional foundation for the military officer.
The classical theorists were not all alike. Clausewitz and Sun Tzu agreed that the maximum concentration of forces was the key to winning the decisive battle and overthrowing the enemy, but unlike Clausewitz’s On War, Sun Tzu’s theory emphasized the relevance of deception in the achievement of concentration at the decisive point. For Sun Tzu, concentration is not simply amassing the largest number of forces, as Clausewitz would have advocated, but instead it meant manipulating the enemy’s perceptions so that he will fight on terms friendly to the concentrating side. Deception played a central role in Sun Tzu’s art of war--deception is at the heart of war--whereas for Clausewitz, deception was not important and even less practical on the battlefield. Many of the differences between the classical works can be traced to differing historical environments.
Although there are differences between the works of the classical theorists, there are also a number of important similarities. As a general rule, the classical theorists were trying to illuminate aspects of the timeless nature of war, and consequently downplayed the particular nature of warfare in their lifetimes. The classical theorists are almost unique for their attempts to construct a universal theory of war--war itself as opposed to warfare in any particular era or in any particular form--based on a relatively large and historically long view of war. Clausewitz’s historical studies reached back to antiquity. Both Sun Tzu and Clausewitz, separated by two thousand years and a cultural divide, came up with very similar theories of war--both arrived at roughly the same constant interaction between irrationality, non-rationality, and rationality--but then again this should not surprise since both were examining the same basic phenomenon and both approached their subject holistically.
For Clausewitz, the purpose of theory is explanation, not prescription. Accurate theory must account for moral forces, a reactive enemy of independent will, and uncertainty, which Clausewitz labored hard to put together in On War. He also believed that because tactics were determined largely by material factors, it much easier for the theorist to address tactics than strategy. This observation remains as true today as it was in Clausewitz’s day.
The timeless nature of war, to the extent that it can be said to exist, was captured well by Clausewitz and his formulation of war as a continuation of politics in a particular form. Clausewitz and Sun Tzu shared a belief in the predominance of politics in war and in devising an appropriate strategy to protect the national interests; both understood the primacy of national interests and the central importance of war in protecting the life of the state. Clausewitz argued clearly for the subordination of military operations to political considerations, but the American way of war has rejected this often, as well as resisting the necessity, at times, of fighting limited wars for limited political aims. Current strategic theory accepts that political purpose must dominate all strategy, a concept derived from Clausewitz’s pronouncement about war as a continuation of policy by other means. Political purpose is expressed in policy, and policy is the expression of the desired end state sought by the government. Policy dominates strategy by its articulation of the end state. If Clausewitz was correct about the relationship between war and policy then American military leaders will find themselves unable to avoid the pressure of political demands because this is part of the nature of war itself.
The classical military thinkers have long understood that war resides at least somewhat within a human psychological realm, and not just in a physical realm of missiles, pikes, flintlocks, and rifles. Sun Tzu considered all warfare to be based on deception, a quintessentially human psychological phenomenon, and Clausewitz understood war to be essentially a psychological struggle to break the opponent’s will to resist. These bare human dynamics will not change and so the insights that have been gleaned by the classical theorists will presumably still apply today and in the future.
It is obvious but true that changes over the centuries from antiquity up to the Napoleonic era have touched every aspect of human life so it would seem natural to question whether war itself has changed to the point that ancient texts on the nature of war can be scrapped for good. In the political dimension kingdoms and empires have given way to states and non-state actors. Technological changes have transformed the physical parameters of war on an almost constant basis, drastically changing rates and methods of movement, means of communication, lethality, and modes of engagement from face-to-face clash of sword and shield to long-distance missiles and smart bombs.
Twentieth century warfare was completely altered by industrialization, mechanization, and total warfare involving entire societies. The twentieth century saw the total wars of 1914-1918 and 1939-1945, which approximated Clausewitz’s concept of absolute war, or at least realized the theory of nations-in-arms organized around unconditional war aims. On the other end of the spectrum, the same century saw highly controlled limited wars for limited political gains. Both varieties of unlimited and limited wars were anticipated by Clausewitz, though he appeared to focus more on the former, probably because of the dramatic national wars of his times.
Twenty-first century warfare has been identified with the information revolution, massive digitization, and the mix of traditional and irregular forms of warfare, non-state actors, and asymmetric means (not that none of these were ever present in warfare before). Despite the numerous arguments for new forms of warfare, or that the nature of war is changing due to revolutionary social and technological changes, the argument can be made that in fact the U.S. military has yet to fully internalize the lessons of the classical theorists. According to one researcher, the U.S. Army espouses the theories of Clausewitz in its programs of military study but does not always adhere to Clausewitz’s insistence that the military is an instrument of policy, but instead tries to mold the views of the political leadership in a way that those views are more compatible with the service’s preferred approach to war. War in the future will take place in new social and cultural contexts and will feature new technology, to be sure, nevertheless war in the twenty-first century will still be organized violence in pursuit of political objectives.
This century has so far been witness to wide-spread and profound changes in technology, advanced digitization, communications, and globalization, growing population and natural resource strains, and an apparent rise in transnational terrorism (although this last may turn out to be more perceived than reality). In the face of such tumultuous change it would be natural to question whether the nature of war will remain unchanged through this all. Does Clausewitz’s rational model of war still apply with a growth in non-state actors, and do centers of gravity still apply to non-state and terrorist actors? A recent study of Clausewitz’s theories with respect to the current environment of irregular threats and asymmetric strategies concludes that while adjustments need to be made as to what exactly constitutes the elements of the remarkable trinity and what exactly constitutes a center of gravity, the classical theories still apply to a remarkable degree to the current wars against terrorism.
Clausewitz observed that the nature of war is both changing and unchanging--chameleon-like. Unfortunately for the student of war there are many military publications on the unchanging principles of war that amount to not much more than declarations of immutable laws of war attached to selected historical examples. Despite this, classical works including those of Sun Tzu, Thucydides, Machiavelli, and Clausewitz make more compelling arguments for an unchanging nature of war. The core reason for the continuing relevance of the classical theorists is because they succeeded in illuminating portions of human nature having to do with organized violence for political ends--control and influence over other organizations. So while it may be understandable to focus on the changing nature of warfare with respect to weapons, and methods of transportation and communication, in fact the classical theorists were more concerned with the unchanging nature of war, and their observations and theories continue to apply to war today because their insights are into the political dimension of human nature. With respect to the unchanging nature of war, the classical theories still apply.
The classical theories of war still apply to war in the twentieth- and twenty-first centuries. The logic of strategy and the nature of the art of war is more timeless than parochial. Many aspects of war from planning to combat leadership seem to have remained relatively immutable through the ages and across cultures, if the vast collections of military history are any guide. At the same time that the classical theories of war still apply to war, we must never stop challenging our theories especially against new circumstances and in light of new technologies of war. It is important to guard against allowing classical theories to substitute for practical and reasoned thought and analysis of current problems and issues--guard against any tyranny of classical thought. The importance of regular and intense reassessment of theory and principles especially when confronting new enemies or technologies cannot be overstated.
There are theorists who limit war to conflict between states and thus call into question the relevance of Clausewitz today. While the nation-state has served as the cornerstone unit in international relations it does not follow that war can only be defined from that construct. Although I do not believe that Clausewitz’s theories only apply to the nation-state, of the form that he witnessed in his lifetime, those authors who argue that his relevance is waning in direct proportion to the fading prominence of the state may be jumping the gun--a decreasing role of the state is still more conjecture than reality. The state will share the international stage with more alternate forms of political organization and power than in the period from the French Revolution to the end of the Cold War, in line with many studies of globalization, but it is not clear that the state is actually being supplanted permanently.
Until the future becomes reality, and using history as an imperfect guide, it can be assumed that future conflict will continue to arise from competing policies, over shortages in natural resources, from the bellicosity of nationalism, terrorism, and that the primary way in which human political organizations will resolve policy disputes will continue to be, at times, war. It is doubtful that this international dynamic will change any time soon, and given an essentially unchanging human nature, and the belief that war rests firmly within the bedrock of human nature, the insights garnered by the classical theorists will still apply as we face war in the future. The ideas that non-state actors wielding weapons of mass destruction, and that war more and more will entail the blurring of military and non-military activities, such as nation-building and peace enforcement, means that the considered views of the classical theorists should be closely reviewed for persistent themes as well as cautions. This process of constant study can enable future leaders to not miss some basic unchanging principles in the use of military force.
1. Teddy C. Cranford, A Methodology for Developing U.S. Naval Doctrine for the 21st Century (Fort Leavenworth, KS: U.S. Army Command and General Staff College, Thesis, 2 June 1995), 55.
2. See Robert Callum, “War as a Continuation of Policy by Other Means: Clausewitzian Theory in the Persian Gulf War,” Defense Analysis 17, no. 1 (2001): 59-72.
3. Brian Bond, “The Indecisiveness of Modern War,” Military Review 47 (December 1967), 48.
4. Peter Munson, “The Return to Attrition: Warfare in the Late Nation-State Era,” Strategic Insights 6, no. 6 (December 2007), 3.
5. Paul E. Snyder, Revolution or Evolution? Combined Arms Warfare in the Twenty-First Century (Fort Leavenworth, KS: U.S. Army Command and General Staff College, Thesis, 1999), 9.
6. Derek M. C. Yuen, “Deciphering Sun Tzu,” Comparative Strategy 27, no. 2 (2008), 184.
7. See Richard M. Swain, “‘The Hedgehog and the Fox’: Jomini, Clausewitz, and History,” Naval War College Review 63, no. 4 (Autumn 1990): 98-109.
8. Jeffrey Record, The American Way of War: Cultural Barriers to Successful Counterinsurgency, Policy Analysis no. 577 (Washington, DC: CATO Institute, 1 September 2006), 4.
9. Harry R. Yarger, “Toward a Theory of Strategy: Art Lykke and the Army War College Strategy Model,” in U.S. Army War College Guide to National Security Issues, Vol. I: Theory of War and Strategy, ed. J. Boone Bartholomees, Jr. (Carlisle, PA: U.S. Army War College, June 2008), 44.
10. Steven Metz and Raymond A. Millen, Future War/Future Battlespace: The Strategic Role of American Landpower (Carlisle Barracks, PA: Strategic Studies Institute, U.S. Army War College, March 2003), 19.
11. James R. Howard, Preparing for War, Stumbling to Peace: Planning for Post-Conflict Operations in Iraq (Fort Leavenworth, KS: School of Advanced Military Studies, United States Army Command and General Staff College, Monograph, 2004), 53-54.
12. Christopher Papaj, “Clausewitz and 21st Century Warfare,” (Carlisle, PA: U.S. Army War College, Strategy Research Project, 15 March 2008), 20.
13. See Colin M. Fleming, “New or Old Wars? Debating a Clausewitzian Future,” Journal of Strategic Studies 32, no. 2 (2009): 213-241.