Is Clausewitz’s Conception of the Relationship Between War and Politics Still Relevant in the Twenty-First Century?

Clausewitz’s conception of the relationship between war and politics remains highly relevant in the twenty-first century, although it must be applied flexibly rather than mechanically. In On War, Clausewitz insists that war is not an autonomous sphere governed only by violence or military technique. Instead, it arises from political purpose and remains subordinate to it: war is “a continuation of policy by other means,” and “the political object is the goal, war is the means” (Clausewitz, 1976: 28–29). This makes politics central not only to the outbreak of war but also to its conduct and limits. Clausewitz further argues that the political object determines the military objective and the degree of effort thought worthwhile, so that wars may range “from a war of extermination down to simple armed observation” depending on the importance of the political aim (Clausewitz, 1976: 20). His argument therefore offers more than the general claim that war is political: it provides a framework for explaining how political objectives shape the nature and intensity of warfare.

Mary Kaldor challenges the adequacy of this framework for contemporary conflict. She argues that many twenty-first-century wars are “inconclusive, long lasting and have a tendency to spread,” rather than moving towards decisive resolution in a classically Clausewitzian sense (Kaldor, 2010: 271). In her view, contemporary wars are frequently sustained by fragmented political dynamics involving state and non-state actors, making the relationship between military action and political purpose much less coherent than Clausewitz appears to suggest (Kaldor, 2010: 274–275). This essay argues, however, that Kaldor’s critique qualifies Clausewitz more than it refutes him. Clausewitz remains relevant because war is still fought for political purposes, and those political objectives continue to shape both the conduct and intensity of violence. Yet Kaldor is right that in many contemporary conflicts those purposes are more fragmented, and the outcomes of violence more inconclusive, than Clausewitz’s classical formulation appears to imply.

Clausewitz’s Conception of War as a Political Instrument

Clausewitz’s most important contribution to this debate is his insistence that war cannot be understood apart from politics. His statement that war is “a continuation of policy by other means” is not merely a famous phrase; it is the centre of his understanding of war as a political instrument rather than an end in itself (Clausewitz, 1976: 29). War remains a distinct activity, with violence as its means, but it is still directed towards aims set by policy. This is why Clausewitz insists that “the political object is the goal, war is the means,” and that means can never be considered separately from the ends they are meant to serve (Clausewitz, 1976: 29). In other words, war is not meaningful on its own terms. It only becomes intelligible when read in relation to the political purposes that generated it.

This point is especially significant because it rejects the idea that war becomes detached from intention once fighting begins. Clausewitz explicitly states that war “springs from some political purpose,” and that policy remains the “supreme consideration” in its conduct (Clausewitz, 1976: 28–29). Politics does not disappear once violence starts; instead, it continues to shape how military force is used. War may develop its own pressures and constraints, but these do not sever it from political purpose. Rather, they affect the manner in which political objectives are pursued. War is therefore political in origin, political in direction and political in limitation.

That insight remains powerful because it provides a way of understanding war as purposeful rather than purely chaotic. States, insurgent groups and other armed actors do not usually fight for violence alone. They fight to secure territory, preserve regimes, deter enemies, establish authority, destroy rival political orders, or impose new ones. Even where those objectives are morally indefensible, internally contradictory or strategically unrealistic, they are still political objectives. Clausewitz’s enduring relevance lies in this basic insight: organised violence remains bound to political purpose. The actors involved in war may have changed and the forms of warfare may have evolved, but war still derives its meaning from the ends it is meant to serve.

Political Objectives and the Intensity of Fighting

Clausewitz’s theory becomes even more relevant when he explains the connection between political objectives and the intensity of fighting. He argues that the political object determines the military objective and the amount of effort regarded as justified in achieving it (Clausewitz, 1976: 20). This is one of the strongest aspects of his continuing usefulness, because it shows that war is not only political in a broad philosophical sense. Its scale, scope and violence are conditioned by the value attached to the political aim being pursued.

Clausewitz does not claim that all wars inevitably become absolute wars in practice. Rather, he distinguishes between the abstract logic of war and the realities of actual conflict. In practice, war is shaped by political considerations, and political aims differ in importance. If the political objective is limited, the war is likely to remain limited. If the political stakes are considered fundamental, the war is more likely to approach greater extremes of effort and destruction (Clausewitz, 1976: 20, 28–29). Strong motives make war “approach its abstract concept,” whereas weaker motives make it appear more plainly as a political instrument among others (Clausewitz, 1976: 29). Clausewitz therefore offers a theory of variation in warfare rather than a claim that every war necessarily culminates in total violence.

This point is central to the question because it shows how tightly war is connected to politics in Clausewitz’s thought. Politics shapes not only the decision to fight but also the level of sacrifice, mobilisation and destruction thought acceptable. The intensity of fighting depends on what political actors believe is at stake. A limited political aim does not justify unlimited violence; by contrast, war linked to regime survival, existential security or major territorial loss is far more likely to generate intense and prolonged combat. This remains highly relevant in the twenty-first century, where wars continue to differ dramatically in scale and brutality. Contemporary military technology may alter the means available, but it does not eliminate the political logic that governs decisions about how much force to use. Clausewitz’s framework still helps explain why some wars remain restrained whereas others become devastating: the answer lies in the perceived significance of the political object.

Mary Kaldor’s Critique of Clausewitz

Mary Kaldor challenges this Clausewitzian framework by arguing that the proposition that war tends towards extremes no longer captures the character of many contemporary conflicts (Kaldor, 2010: 271). In her account, today’s wars are not driven by a classical “urge to decision” but are instead prolonged, dispersed and often inconclusive (Kaldor, 2010: 272). Rather than resembling the large-scale interstate wars most closely associated with Clausewitz, many contemporary conflicts involve mixtures of state forces, militias, insurgents, networks and external actors operating in fragmented political environments.

Kaldor’s argument is not that war has ceased to be political. Rather, she suggests that the politics of contemporary war have changed. Instead of coherent policy directed towards decisive military victory, contemporary conflicts may be sustained by fragmented authority structures, exclusionary identities and political economies that benefit from the continuation of violence (Kaldor, 2010: 274–275). She describes such conflicts as a kind of “mutual enterprise,” in which direct combat is often avoided, civilians become central targets, and the tendency is towards “war without end” or “permanent inconclusive war” rather than clear resolution (Kaldor, 2010: 274–275). On this view, treating such wars as if they were classical contests of wills may actually worsen them, because the central problem is no longer how to secure decisive victory but how to prevent or end protracted violence (Kaldor, 2010: 279).

This critique matters because it directly challenges any simple claim that Clausewitz remains fully adequate to the present. If many twenty-first-century wars fail to culminate in decision, and if violence itself becomes politically productive for those engaged in it, then war no longer appears to be an instrument subordinated to clear policy in the classical sense. Kaldor therefore forces us to ask whether Clausewitz’s conception is broad enough to explain conflicts in which political purpose is fragmented, authority is dispersed, and military escalation fails to generate meaningful political outcomes.

Evaluating Kaldor

Kaldor’s critique is persuasive in showing that many contemporary wars do not resemble the decisive interstate conflicts often associated with Clausewitz. She is also right that military escalation frequently fails to generate stable political resolution. In this respect, she exposes the limits of any rigidly classical reading of Clausewitz. However, her argument does not fully refute Clausewitz’s conception of the relationship between war and politics. Instead, it qualifies it.

The central reason is that even the conflicts Kaldor describes remain political. They may involve fragmented politics, transnational networks or identity-based mobilisation, but they are not apolitical. Violence is still used to gain power, control territory, defend authority, preserve a political order or exclude rival communities. In that sense, Clausewitz’s deepest claim still holds: war remains inseparable from politics. Kaldor shows that the content and structure of politics have changed, not that war has ceased to be political.

The secondary literature helps make this point more clearly. Schuurman argues that “new wars” scholars often exaggerate the break between Clausewitz and contemporary conflict, overlooking the flexibility of Clausewitz’s thought and the extent to which it can illuminate civil wars and insurgencies as well as classical interstate conflict (Schuurman, 2010: 96–97). Clausewitz did not claim that all wars would take a single fixed form. On the contrary, he recognised that war changes its appearance according to historical and political circumstances.

Similarly, Kalyvas challenges the distinction between “old” and “new” wars by arguing that the supposed novelty of recent conflicts often rests on a distorted understanding of both present and past wars (Kalyvas, 2001: 100–101). He suggests that contemporary wars are often described through incomplete information, while older wars are retrospectively simplified and idealised (Kalyvas, 2001, p. 100). Taken together, these arguments weaken the claim that Clausewitz has simply been superseded by a wholly new era of warfare.

The strongest conclusion, then, is that Kaldor modifies Clausewitz rather than invalidating him. She rightly warns against applying a narrow and rigid model of decisive interstate war to all contemporary conflict. Yet she does not overturn the broader Clausewitzian insight that war remains bound to political purpose. Clausewitz is still relevant, but his relevance lies in explaining the political nature of war, not in predicting that all wars will culminate in clear decision.

Case Study: Gaza and the Problem of Political Outcomes

The Gaza war provides a particularly revealing test of both Clausewitz and Kaldor because it demonstrates, at the same time, the enduring political nature of war and the difficulty of converting military violence into stable political outcomes. At the most basic level, the conflict strongly supports Clausewitz’s argument that war is political. The military campaign has been tied to explicit political aims: destroying Hamas as an organised force, restoring Israeli deterrence after the attacks of 7 October, defending the state, and shaping the future political order of Gaza. These objectives may be contested, internally contradictory or difficult to achieve, but they are clearly political. Military force is therefore not operating autonomously; it is being used in pursuit of political ends, exactly as Clausewitz suggests when he insists that war is subordinate to political purpose (Clausewitz, 1976: 28–29).

The war also demonstrates Clausewitz’s point about the relationship between political objectives and the intensity of fighting. Once leaders define the stakes as existential or strategically vital, they become more willing to employ extensive force and sustain prolonged conflict. The scale of destruction in Gaza is therefore not explained by military capability alone. It reflects the perceived value of the political object at stake and the level of effort judged necessary to secure it. In that sense, Clausewitz’s argument remains highly illuminating: the degree of force considered acceptable is inseparable from what political leaders believe is under threat or what they think can be achieved through violence (Clausewitz, 1976, p. 20). The conflict thus confirms that political purpose continues to shape not only the decision to fight but also the intensity and persistence of warfare.

At the same time, Gaza reveals the limits of a straightforwardly instrumental reading of war, and this is where Kaldor’s critique becomes powerful. The existence of political objectives does not mean that military action can successfully realise them. In Gaza, one of the central problems has been the widening gap between the scale of military violence and the possibility of a clear, durable political outcome. The use of overwhelming force has not automatically produced stable political decision; instead, it has generated devastation without resolving the underlying political conflict. This closely reflects Kaldor’s argument that contemporary wars may become prolonged and inconclusive, not because they lack political content, but because military escalation fails to translate into meaningful settlement and may even deepen the dynamics of insecurity and fragmentation (Kaldor, 2010: 271, 274–275). The war is therefore political in motivation but uncertain in outcome.

This point is especially important because it shows that Clausewitz and Kaldor are not simply opposites. Gaza confirms Clausewitz at the level of principle: war remains an instrument of political purpose. Yet it also confirms Kaldor’s warning that in many twenty-first-century conflicts, violence does not lead to the kind of decisive outcome associated with classical models of war. Instead, political aims may remain contested, multiply, or become harder to achieve as violence intensifies. The Gaza war therefore suggests that Clausewitz is still indispensable for understanding why the conflict is fought and why it is fought with such intensity, but Kaldor is equally valuable in explaining why that violence does not necessarily produce political resolution. The relationship between war and politics still exists, but in contemporary conflict it is often unstable, fragmented and resistant to closure.

Conclusion

Clausewitz’s conception of the relationship between war and politics remains highly relevant in the twenty-first century because war continues to be fought for political purposes and directed towards political ends. His insistence that war is “a continuation of policy by other means” still provides one of the strongest frameworks for understanding why wars occur, how they are fought, and why their intensity varies according to the importance of the political object (Clausewitz, 1976: 20, 28–29). This is the central reason his ideas endure: war is not autonomous violence, but organised force shaped by political purpose.

Mary Kaldor nevertheless offers an important critique. Her analysis of contemporary conflicts as prolonged, fragmented and inconclusive rightly exposes the limits of applying Clausewitz too rigidly to modern warfare (Kaldor, 2010: 271, 274–275, 279). Yet her argument ultimately qualifies Clausewitz rather than displacing him. Even in the conflicts she describes, violence remains political, however diffuse or unstable the politics involved may be. Clausewitz therefore remains relevant not because he provides a complete model of every form of contemporary conflict, but because his core insight still holds: war, even in the twenty-first century, remains inseparable from politics.

References

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