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The Mirage of Post-Clausewitzianism: Understanding War and Politics on the Frontier of Clausewitzian Thought

To cite this article: Milevski, Lukas, “The Mirage of Post-Clausewitzianism: Understanding War and Politics on the Frontier of Clausewitzian Thought”, Military Strategy Magazine, Special Edition, “The Continuing Relevance of Clausewitz”, December 2020, pages 16-20.

It used to be fashionable to decree that Carl von Clausewitz and On War had become obsolete, especially in the 1990s when Martin van Creveld, John Keegan, and Mary Kaldor each developed notions of war and warfare which were purportedly post-Clausewitzian. Keegan even suggested that war had almost never been and actually should not be Clausewitzian. None of them produced a convincing portrayal of post- or non-Clausewitzian war and each received substantial pushback from the field of strategic studies, particularly anyone acquainted with Clausewitz’s work. Attempts to replace Clausewitz have diminished since then, the most notable of the few by Emile Simpson in 2012.

Nonetheless, such attempts provoke a question: what could post-Clausewitzian war actually look like? In a certain sense, this is the same as asking to identify the limits of Clausewitz’s theory of war. However, not all limitations are equally significant. Clausewitz did not write about sea power, or technology, or the economics of war, each of which represents a limitation, but one of omission rather than of logic. They do not fatally affect the logic or structure of Clausewitz’s theory of war. Such limitations of omission have been compensated by subsequent thinkers such as Julian Corbett, who imported some of Clausewitz’s ideas into the study of sea power. Limitations of logic are more important; in principle they represent the basis for repudiating the Clausewitzian system of knowledge for understanding war and replacing it with something else.

This article begins by briefly explaining the various cases made against Clausewitz by van Creveld, Keegan, Kaldor, and Simpson, what these critiques all have in common, and what they reveal about Clausewitz’s theory of war. Thereafter, the focus shifts to the cultural context of the critics and its importance in providing definitions of key concepts such as policy and politics which are not only incompatible with Clausewitz’s theory of war but are even in and of themselves problematic.

The Cases Made Against Clausewitz

Harold Winton has suggested that theory serves four distinct purposes: explanation; categorization; establishing relationships with other fields; and anticipation.[i] All four of the major challenges to Clausewitz of the past 30 years (van Creveld, Keegan, Kaldor, and Simpson) have focused on one single element of theoretical purpose: establishing relationships. All four also focused on a single relationship, between war and politik, whether translated as policy or politics.

Martin van Creveld sought to provide an explicitly post-Clausewitzian perspective on war: “this work aims at providing a new, non-Clausewitzian framework for thinking about war”.[ii] He did this by (incorrectly) suggesting that the Clausewitzian trinity comprised the government, army, and people, all presumed to be possessed by a state: “That organized violence should only be called ‘war’ if it were waged by the state, for the state, and against the state was a postulate that Clausewitz took almost for granted”.[iii] Further, “[a]rmies were defined as organizations which served the government, whether monarchical, republican, or imperial.”[iv] Thus van Creveld concluded that “Clausewitz’s ideas on war were wholly rooted in the fact that, ever since 1648, war had been waged overwhelmingly by states.”[v] The state-orientation he forced on Clausewitz infected his understanding of politics as well:

Whatever the exact meaning of the term ‘politics,’ it is not the same as ‘any kind of relationship involving any kind of government in any kind of society.’ A more correct interpretation would be that politics are intimately connected with the state; they are, indeed, the characteristic form that power-relationships assume within the kind of organization known as the state. Where there is no state, as was the case during most of human history, politics will be so mixed in with other factors as to leave room neither for the term nor for the reality behind it.[vi]

Thus van Creveld characterized Clausewitz’s theory of war as state-centric in such a way that one of the key relationships the latter enunciated—that war is a continuation of politics with the admixture of violent means—breaks down in all but a very particular set of circumstances. He mischaracterizes both war and politics.

John Keegan similarly assaults the war-politics link; the first sentence of his first chapter starkly asserts “[w]ar is not the continuation of policy by other means.”[vii] Although he acknowledges that a fixation on ‘policy’ is a quirk of translation and suggests that politik should more accurately translate as ‘political intercourse’, he then lofts the same state-centric banner as van Creveld. “It implies the existence of states, of state interests and of rational calculation about how they may be achieved. Yet war antedates the state, diplomacy and strategy by many millennia.”[viii] His reasoning for innately associating politics and the state was even weaker than that of van Creveld; he simply passed it over as a given. Instead, he contrasted politics with culture by suggesting that non-Western forms of warfare “defied altogether the rationality of politics as it is understood by Westerners … to perceive how incomplete, parochial and ultimately misleading is the idea that war is the continuation of politics.”[ix] Keegan, although he characterizes war acceptably, mischaracterizes politics even more extremely than van Creveld. Not only is it state-centric, but politics must also be rational in a way understood by the West, otherwise it is not politics. Implicit in Keegan’s writing is the suggestion that the Western understanding of politics is simultaneously right—the rational standard to which all non-Western politics, to be politics rather than culture, must be measured—and wrong—unable to comprehend forms of politics outside the West’s culturally narrow understanding of the phenomenon. Yet, for Keegan, the problem was not the West’s, or his own, understanding of politics, but the relationship between war and politics expressed by Clausewitz.

Mary Kaldor follows van Creveld and Keegan in associating Clausewitz with state-centric understandings of both war and politics, with similarly poor justification. She leaps with even more haste than Keegan from Clausewitz’s definition to invoking the state: “Clausewitz defined war as ‘an act of violence intended to compel our opponent to fulfill our will’. This definition implied that ‘we’ and ‘our opponent’ were states, and the ‘will’ of one state could be clearly defined. Hence war, in the Clausewitzian definition, is war between states for definable political end, i.e. state interest.”[x] Despite mischaracterizing, then critiquing Clausewitz, her ambition was not to supplant him as such, but to highlight differences between her view of the prevalent thinking and what she believed to be empirical reality in Bosnia-Herzegovina in the mid-1990s. Nonetheless, her critique’s focus on the Clausewitzian relationship between war and politics, again misrepresented politics as something inherently state-based and rational.

Of the four critiques of Clausewitz, Emile Simpson’s is the most sophisticated and best elaborated. It also is based on a traditional-Clausewitzian versus contemporary war distinction, particularly regarding the relationship between war and politics. Simpson distinguishes between two such relationships:

“first, the use of armed force within a military domain that seeks to establish military conditions for a political solution, a practice traditionally associated with the concept of war; second, the use of armed force that directly seeks political, as opposed to specifically military, outcomes, which lies beyond the scope of war in its traditional paradigm.”[xi]

The former is purportedly Clausewitzian: military action, on the basis of the physical results achieved, enables new politics to occur, leading to the end of war and a new pattern of interaction between prior belligerents. The latter is an ill-defined concept which seems essentially to boil down to others not interpreting action the same way as the acting belligerent. As Simpson explained using the example of Israel’s 2006 war with Hezbollah, “Israel’s actions in war were not interpreted by the Lebanese people and government, a key strategic audience, in accordance with Israel’s interpretive structure of war. Thus what for Israel was part of a battle in Beirut was for the Lebanese the death of family or friends. The capture of a military objective for Israel was seen by various constituencies, particularly in parts of the Muslim world, as a heroic fight by Hezbollah for Palestinians in Gaza and Islamic militants generally.”[xii] Essentially, it is about being aware of how other parties (not simply the direct enemy) think about one’s military activities. Yet again, the critique focuses on the relationship between war and politics, this time on the basis of differing perceptions of that relationship among belligerents and bystanders.

In concentrating on this one aspect of theory, all these works inadvertently highlight the fundamental problem of trying to imagine post-Clausewitzian war. Clausewitz’s theory of war is highly multi-dimensional and encompasses myriad aspects: a handful of different definitions of war; the wondrous trinity; the methodology of historical kritik by which to study war; the relationship between offense and defense; military genius and the qualities of military command; and so on. Although some of Clausewitz’s insights are less crucial than others, On War alone contains hundreds of pages of insight, let alone other works which Clausewitz also wrote during his lifetime. This leads to the question of how much Clausewitz must be refuted before one’s vision of war is truly post-Clausewitzian? This is not to catalogue and rate his ideas, but rather to suggest that moving past Clausewitz is difficult and complex. It is also why the critics, including but not limited to these four, focused not on the content of Clausewitz’s theory of war but on the one element of theory inherent in defining external relationships with other fields and other key concepts—particularly politik, whether policy or politics. By questioning his relevance in this way one may try to refute Clausewitz without engaging with the bulk of his theory. Van Creveld was honest about this, still recognizing On War as the second best book on war ever written.[xiii] Implicitly it is not that his ideas are wrong, but that the relationships are—or, became wrong over time as social and political conditions changed.

Clausewitz, Culture, and Context

Underlying the critiques of Clausewitz is the assumption that relationships his theory defined between war and politics/policy have been culturally conditioned in an age of states, making his theory state-based with relevance that rises and falls along with the fortunes of the state as a method of political organization. Both policy and politics are therefore activities of and products by the state; they cannot exist beyond it. This is outright wrong. As his writings evolved Clausewitz actually moved away from ascribing the state a dominating role: “In one of his earlier manuscripts, Clausewitz regarded war as the continuation of ‘l’intérêt naturel des états’, being much in conformity with the primacy of policy as we know it today. This gradually however changed first into Staatspolitik and finally into Politik when he wrote his last version of Vom Kriege after 1827.”[xiv] Beyond this factual point, however, it is notable that those making this culturalist critique ignore their own cultural context and its effect on their thinking about key concepts—in particular, on both politics and policy—and in turn how this has affected their judgments on Clausewitz’s theory of war.

Central to the cultural context of the critics is the assumption that policy is inherently rational, where rationality is generally defined using key elements such as a narrow (usually material) understanding of self-interest and the efficient pursuit of goals to maximize gains. Rationality has often been understood in the light of its two potential sources: either human beings themselves are innately rational, or the processes by which humans behave and act in organized social settings may be designed to force otherwise irrational creatures to make rational choices.[xv] This is the culturally dominant understanding of rationality in the West and has been prevalent in the social sciences, from economics to business management and administration, political science, international relations, and indeed strategic studies, since the 1920s, despite recurring challenges to such notions of rationality and rationalism such as those posed by the very occurrences of the Second World War and the Cold War.[xvi] Rationality is a word culturally imbued with very particular meaning.

Thus in combating Clausewitz’s critics, his defenders dispute his purported state-centrism but often not the centrality of rationality to policy; rather, they similarly also assume its importance. Christopher Bassford’s definition of policy is “rational action, undertaken by an individual or group which already has power in order to use, maintain and extend that power.”[xvii] Bassford also leans heavily on rationality in his description of the Clausewitzian trinity, shortening Clausewitz’s primordial violence, enmity, and hatred; play of chance and probability; and subordination to reason simply to irrationality, nonrationality, and rationality.[xviii] Peter Paret similarly invokes rationality as a defining element of policy.

Implicit in both sides of the Clausewitzian debate is therefore the assumption that policy concerns fulfilling narrowly-defined, usually material goals as efficiently as possible to maximize gains. Yet basic acceptance of rationality by Clausewitz’s defenders continues to leave him open to criticism on the basis that often throughout history war has not been a rational instrument of policy or a rational continuation of political intercourse, especially when judging by outcomes. For example, even without the state fixation, Keegan’s criticism still stands if policy is assumed to be inherently rational because policy-makers (and not just non-Western policy-makers) often take broader interpretations of their self-interest and the interest of their polity than mere material benefit, and they often do not seek to maximize gains outright but satisfy themselves with lesser achievements. Such stances exceed the bounds of rationality as it is generally culturally understood in the West—at least in Western academia—yet are politically normal even in the West. The fixation on rationality produces an understanding of politics and policy which cannot even encompass Western politics within and between states, let alone also politics in non-Western and non-state contexts. The rationality focus produces an inapt understanding of political behavior which in turn excludes much political behavior as nonpolitical because it does not fit the definition of rationality. Moreover, this emphasis on rationality is also an inaccurate depiction of Clausewitz’s understanding of politics; his “ideas are more complex than these crude depictions of strict political rationalism suggest.”[xix] Yet the centrality of rationality is so culturally ingrained that, rather than question their own limited and inapt understanding of policy, Clausewitz’s critics attempt to undermine his contention that war is the continuation of politik with grand statements which deride Clausewitz and establish ever grander counter-concepts such as culture.

Simpson’s more distinct critique of Clausewitz is founded on ways of teaching strategy, war, and Clausewitz himself which are culturally unique not just to the West, but even more narrowly to professional Western militaries. Although Simpson did not emphasize states, such teaching tends to emphasize their importance; one may note the military cultural importance of the self-described Clausewitzian Harry Summers’ On Strategy, which depicts—in line with later critics—a state-focused Clausewitzian trinity. Second, it reflects the professional military’s preference to imagine a military-only, politics/policy-free zone of activity in the operational level of war.[xx] Only in such optimistic fantasy thinking does war establish exclusively military conditions for subsequent political consequences, rather than being thoroughly infused by politics throughout the whole experience. As Clausewitz wrote to a colleague, “the political element even extends to the separate components of a campaign; rarely will it be without influence on such major episodes of warfare as a battle, etc. According to this point of view, there can be no question of a purely military evaluation of a great strategic issue, nor of a purely military scheme to solve it.”[xxi] Although Simpson was presumably taught this operational perspective professionally as if it were Clausewitzian thinking, it in fact reflects modern Western military culture and professional predilections rather than Clausewitz himself.


When considering Clausewitz, the critics are actually criticizing but a stylized understanding of Clausewitz, commonly shared but nonetheless wrong. Kaldor comes closer than most to both recognizing and acknowledging this: “it is the stylized notion of war that still profoundly affects our thinking about war and dominates, even today, the way policy-makers conceive of security.”[xxii] This stylization of Clausewitz, and of the understanding of war his caricature came to represent, emerged principally out of the 1970s, to which the popular 1976 Michael Howard and Peter Paret translation contributed, and from which the critics could not escape even as they criticized what they believed to be Clausewitz’s actual theory of war. Hew Strachan has recognized this, writing back in 2007 that

[t]he Clausewitz so readily condemned by commentators of today, such as Martin van Creveld, John Keegan and Mary Kaldor, is the Clausewitz who was fashionable in the 1970s. The fact that the rationality of the “formula” of war’s relationship to policy looks less clear in 2007 does not invalidate it as an interpretative tool. The problem has arisen from its artificial exclusivity, from its being taken so very much out of context. There is much more to On War than one hackneyed catchphrase, and the tragedy for the armed forces of the United States and their allies today is that greater attention to rather more of the text would have provided the intellectual underpinnings for greater self-awareness and strategic sensitivity than has been evident over the last half decade. We need not to ditch On War but to read more of it, and to read it with greater care.[xxiii]

Yet it is not just Clausewitz whom we must treat with greater care. We must treat all of our ideas and their sources with greater care and, in the context of Clausewitz and strategic studies, particularly those ideas to which Clausewitz connects war and to which strategic studies as a field connects itself. Many of Clausewitz’s critics, in lieu of questioning their own knowledge and its contexts, preferred to fault Clausewitz’s theory of war. Today the prospect of wholly surmounting Clausewitz and studying war without him remains a mirage, although the need to move beyond inapt stylizations of Clausewitz, as well as of other key concepts in strategic studies such as war, strategy, politics, and policy, remains eternally necessary.


[i] Harold R. Winton. “An Imperfect Jewel: Military Theory and the Military Profession”, Journal of Strategic Studies 34/6 (December 2011), 855-856.
[ii] Martin van Creveld. The Transformation of War. (New York: The Free Press 1991), ix.
[iii] Ibid, 36.
[iv] Ibid, 38.
[v] Ibid¸ 41.
[vi] Ibid, 125.
[vii] John Keegan. A History of Warfare. (New York: Vintage Books 1994), 3.
[viii] Ibid.
[ix] Ibid, 24.
[x] Mary Kaldor. New & Old Wars. (Cambridge: Polity 2006), 17.
[xi] Emile Simpson. War From the Ground Up: Twenty-First-Century Combat as Politics. (London: Hurst & Company 2012). 1.
[xii] Ibid, 71.
[xiii] Van Creveld, The Transformation of War, 231.
[xiv] George Dimitriu. “Clausewitz and the politics of war: A contemporary theory”, Journal of Strategic Studies 43/5 (2020), 653.
[xv] Hunter Heyck. “Producing Reason” in Mark Solovey and Hamilton Cravens (eds). Cold War Social Science: Knowledge Production, Liberal Democracy, and Human Nature. (New York: Palgrave Macmillan 2012), 100.
[xvi] Ibid, 99-116; Miles Kahler. “Rationality in International Relations”, International Organization 52/4 (Autumn 1998), 919-921.
[xvii] Christopher Bassford. “John Keegan and the Grand Tradition of Trashing Clausewitz: a Polemic”, War in History 1/3 (1994), 326.
[xviii] Edward J. Villacres and Christopher Bassford. “Reclaiming the Clausewitzian Trinity”, Parameters 25/3 (Autumn 1995), 9-19.
[xix] Thomas Waldman. “Politics and War: Clausewitz’s Paradoxical Equation”, Parameters 40/3 (Autumn 2010), 1.
[xx] Hew Strachan. “Strategy or Alibi? Obama, McChrystal and the Operational Level of War”, Survival 52/5 (September 2010), 160.
[xxi] Quoted in Peter Paret & Daniel Moran (eds). Carl von Clausewitz: Two Letters on Strategy. (Fort Leavenworth: US Army Command and General Staff College 1984), 21.
[xxii] Kaldor, New & Old Wars, 17.
[xxiii] Hew Strachan. “A Clausewitz for Every Season”, The American Interest 2/6 (July 2007),