Clausewitz’s On War seemingly finds its continued relevance in the classrooms of military academies around the world (Mierendorff, 2021; Lantis, 2006). With especially US military scholars having turned to Clausewitz after the failures of the Vietnam War, his teachings, though metaphysical in nature, seem to have a concrete impact on actual military tactics (Schwandt, 2019). Describing war as a ‘chameleon’, Karl von Clausewitz’s On War paints a comprehensive philosophical picture of war as more than just a collection of strategies or an extension of politics (Strachan, 2007; Clausewitz, 2008 p. 89).

Answering the question of whether Clausewitz is still relevant in the 21^st century, this essay seeks to distinguish between the philosophical use of Clausewitz as a metaphysical theorist of warfare, and the practical Clausewitz being studied almost biblically in military academies around the world. This distinction stems from what Benoît Durieux describes as the dilemma between what Clausewitz saw as the necessity for a philosophical approach to war, and his personal experiences on the Napoleonic battlefields (Durieux, 2007, p. 253). This dilemma is reflected in Clausewitz’s eventual work through what can be perceived as a demarcation between the philosophical and metaphysical side of Clausewitzianism, and the supposed practical relevance of On War in teaching real, concrete military strategy (Schwandt, 2019; Olsen, 2013. p. 13). Through this distinction between the metaphysical Clausewitz and the practical Clausewitz, this essay argues that On War both is and isn’t relevant in 21^st-century armed conflict.

To better understand whether and how Clausewitz is still relevant in the 21^st century, it is important to consider the very nature of On War. Much of the debate surrounding Clausewitzianism surrounds whether it should be taken as a scientific and concrete basis for actual military strategy, as many in the military academies will argue (Mierendorf, 2021; Schwandt, 2019) or rather as a metaphysical framework in which theories can be built. In its first section, this essay dissects the metaphysical side of Clausewitz’s work. To do so, it tests On War through Karl Popper’s Theory of the Progress of Science. Popper argues that true empirical science should constantly be submitted to inductionist testing (Grünbaum, 1979). If one of those tests turns out to be negative, it empirically shows that the theory is not a set, universal truth. A theory that cannot be falsified in such a way that a negative test result is even possible, cannot be considered positivist, and should, therefore, rather be seen as metaphysics (McLaren, 2006).

This can be applied to Clausewitz’s epistemology. Clausewitz argues from a Kantian tradition of anti-positivist critiques, demarcating a metaphysical ideal ‘Absolute State of War’, against which he sets the less-than-ideal ‘real war’ (Clausewitz, 2008 p. 80; Williams, 2007). Although the Napoleonic wars came close, this ideal ‘Absolute War’has proven impossible, with most conflicts rather belonging to the realm of real wars (Olsen, 2013). Admitting this, Clausewitz declares real war to belong to the realm of chance, and thus, to be unpredictable through rationalist or positivist methodologies (Clausewitz, 2008, p. 136; Williams, 2007). Through his critique of pre-Napoleonic rationalist views of warfare as a predictable, positivist system, he actively counters the scientificality of war. However, in doing so he creates an unfalsifiable, self-referential metaphysical framework (Williams, 2007, pp. 8-9). This concretely means that Clausewitz’s framework can always be defended through Clausewitz. Any counter-argument can be debunked by a different interpretation of the distinctions between real war and the ‘Absolute State of War’, a self-referral to the Trinity, or a different view on how Clausewitz meant what he wrote or should be interpreted (Olsen, 2013, pp. 6-7; Durieux, 2007, pp. 251-252). This does not at all show that Clausewitz should be considered irrelevant; on the contrary, it sets Clausewitzianism as a flexible and multi-interpretable metaphysical framework through which multiple theories of war and approaches to the practical sides of a conflict can be derived.

The metaphysical Clausewitz “does not wish to propose solutions for the military commander” (Durieux, 2007, p. 252) but does provide the reader with his own empirical observations of armed conflict (Clausewitz, 2008). This we can call the practical Clausewitz. Many colleges of strategic studies have misinterpreted the practical Clausewitz as a timeless, positivist theory of war as a rational phenomenon, disregarding the non-scientific nature of his work (Fleming, 2013, p. 172). Basing actual strategies on Clausewitz’s outdated models of warfare will inevitably lead to military mishaps: as Mary Kaldor (2012) argues in her work on New Wars, the actual practical sides of warfare have inarguably moved to a post-Clausewitzian phase. The end goal of pure military defeat has, for example, in many cases been replaced by the goal of creating a law-and-order-based international system (Kaldor, 2012, pp. 215-216, 219). The idea of absolute war as a practically reachable ideal is no longer relevant, nor are the ways in which Clausewitz argues a war can be quickly won through swift, duel-like actions (Kaldor, 2010). Regarding the more metaphysical nature of war, one can argue Clausewitz’s assessments that “war is politics by other means” (Clausewitz, 2008, p. 87) and his explanation of war as a trinity to still be relevantas “visualisations of interplay and reciprocity” (Fleming, 2013, p. 173; Kaldor, 2012, p. 214-215). But, as observed by Jamie Schwandt, it was the tendency to adhere to literal interpretations of the practical Clausewitz that are to blame for many of the US military’s recent mishaps (Schwandt, 2019).

Even Mary Kaldor, whose New Wars thesis is often depicted as a leap into post-Clausewitzianism, does not deny the relevance of the metaphysical Clausewitz. Rather than fully discarding On War and its premises, her essay on Inconclusive Wars presents her theorem as a reinterpretation of Clausewitz’s central tenets of the trinitarian conception of war, the primacy of policy and politics and the dialectic of ideal and real war (Kaldor, 2010). Small wars, civil wars and other kinds of New Wars, which in 21^st-century warfare are more common than the wars on which Clausewitz based his writings, do fit within the broader central tenets (Kaldor, 2012, pp. 214-215; Kaldor, 2010). The more practical sides of his writings, however, tried and tested on empirical observations of the realities of Napoleonic warfare, have lost their applicability. Where does Clausewitz, for example, stand when it comes to the temporal suspension of war, the standing still, that is so common in 21^st-century conflict (Kaldor, 2010)? Or how does he account for the role of God as a point of gravity in many of the modern religion-based militant movements (Lind & Thiele, 2015)? While the Clausewitzian metaphysics described above set a highly useable framework to create theories with which to explain these 21^st-century military occurrences, On War certainly does not provide us with a theory that covers the actual practicalities of modern warfare.

Clausewitz describes war as, amongst other things, a chameleon, ever-changing and adapting to its contexts and circumstances though steadfast in its theoretical and philosophical core. The same, this essay argues, can be said about Clausewitz himself. Whether that makes Clausewitz more or less relevant is very much up to debate: Clausewitz’s work seems caught in what Olson describes as a “scholarly fog of interpretations” (Olsen, 2013). Whereas more enquiries on the deeper nature of war often claim that On War is still very much relevant in the 21^st century, analytical argumentations cast doubt on its usefulness in researching actual conflicts. Whether this asserts or denies his relevance depends on how you look at using Clausewitz, rather than on the actual work itself. For On War, much like the metaphorical chameleon that is war itself, adapts to its contexts and its interpretation. It is, therefore, that this essay has argued for a distinction between the practical Clausewitz and the metaphysical Clausewitz.

This distinction neither confirms nor denies his irrelevance, but does show that the validity of his writings depends on how you look at them. From the metaphysical lens, a lot of the arguments against Clausewitz can be debunked. Whilst doubt can be cast on the theoretical model of war as a science because of On War’s unfalsifiable epistemology, the metaphysical Clausewitz creates a basic framework on which modern theories can still be based. From an analytical perspective, however, one can argue that Clausewitz’s practical observations of war have become irrelevant. With 21^st-century warfare playing out on a smaller, more localised and temporarily extended scheme, the broader ideas promoted in On War do not hold ground. In a world of small-scale, asymmetrical and autonomous conflict, the Clausewitzian frameworks can be used to create novel, tailored military theories. As On War’s own empirical and practical observations have become outdated, those theorists clinging to classical interpretations of the practical Clausewitz will find themselves on the losing side of the conflict.

To best analyse On War would, thus, mean to distinguish between the outdated practical Clausewitz and his broader metaphysical framework, in which both relevant and irrelevant theories and well as interpretations, can be found. The continued relevance of Clausewitz in the 21^st century can therefore best be found not in his own work but rather in the framework he set up and the continued active debates On War have spurred over time.

Bibliography

Bassford, C. (2007). The primacy of policy and the “Trinity” in Clausewitz’s mature thought. In Hew Strachan and Andreas Herberg-Rothe (eds.) Clausewitz in the Twenty-First Century. Oxford University Press.

Durieux, B. (2007). Clausewitz and the two temptations of modern strategic thinking. In  Hew Strachan and Andreas Herberg-Rothe (eds.) Clausewitz in the Twenty-First Century. Oxford University Press

Fleming, C. M. (2013) Clausewitz’s Timeless Trinity: A Framework for Modern War, Taylor & Francis Group.

Grünbaum, A. (1979). Is Freudian psychoanalytic theory pseudo-scientific by Karl Popper’s criterion of demarcation? American Philosophical Quarterly, 16(2), 131–141.

Herberg-Rothe, & Strachan, H. (2007). Clausewitz in the Twenty-first Century. Oxford University Press.

Kaldor, M. (2012) New and Old Wars: Organized Violence in a Global Era / Mary Kaldor. Third edition. Polity.

Kaldor, M. (2010). Inconclusive wars: Is Clausewitz still relevant in these global times? Global Policy, 1(3), 271–281.

Lantis, J. S. (2009). Strategic culture: From Clausewitz to constructivism. In Strategic Culture and Weapons of Mass Destruction (pp. 33-52). Palgrave Macmillan, New York

Lind, W. S., Thiele, G. A. (2015) 4th generation warfare handbook. Castalia House, Finland

McLaren, N. (2006). Popper Versus Freud. Australian & New Zealand Journal of Psychiatry, 40(1), 97–98

Mierendorff, J. (2021). Is Carl Von Clausewitz still relevant in the 21st century? Pointer: Journal of the SAF.

Olson, W. (2013). The continuing irrelevance of Clausewitz. Small Wars Journal | Jul, 26(1), 55am.

Schwandt, J. (2019) Why we should stop teaching Clausewitz. Task&Purpose. https://taskandpurpose.com/opinion/just-say-no-to-clausewitz/ Last accessed on 27-02-2022.

von Clausewitz, C. (2008). On War. (Howard & P. Paret, Eds.). Princeton University Press.

Williams, J. (2007). Epistemology and War—The Rise of Rationalism and Clausewitz’ Critique of Pure War. https://severalfourmany.wordpress.com/2007/09/30/3043/ Last accessed on 26-02-2022.

Further Reading on E-International Relations

• Misreading Clausewitz: The Enduring Relevance of On War
• Is Dependency Theory Relevant in the Twenty-First Century?
• Is the Nature of War Changing? Time to Avoid a Supposedly Unavoidable Question
• Mapping the Nexus Between Security and Development in the 21st Century
• Cyber War Forthcoming: “It Is Not a Matter of If, It Is a Matter of When.”
• Fighting over War: Change and Continuity in the Nature and Character of War