The rules of war are absurd, but necesssary

How can war ever be just?

During the invasion of Ukraine, we have heard frequently terms like ‘war crime’ and ‘just war’. In a fight to the death, when your aim is the taking of the life of another human being, the idea of there even being such a thing as a ‘crime’ or ‘justice’ in that context is seemingly absurd. Furthermore, institutions like NATO are endlessly discussing the ‘rules of conflict’, while in the UN Security Council Russia absurdly has a veto ruling out action against its own aggression. Seeming absurdity on top of seeming absurdity. But the rules of war are necessary. Defining terms like ‘war crime’ and ‘just war’ do have a clear and important role to play, even in the face of the chaos, the heartache and the bloody killing of war, writes Saba Bazargan-Forward


Ukraine’s heroic struggle against Russia’s wanton aggression has elicited a lot of talk about the possibility of a ‘morally just’ war. At first, the very idea of such a war might seem absurd. After all, wars are horrific. They represent humanity at its worst, in which our all our ingenuity, our energies, our capacities, are aimed at killing one another. “War is cruelty,” William Tecumseh Sherman famously said, “and you cannot refine it”. Any attempt to unearth moral principles for war seems not just foredoomed to failure but also morally perverse. On this view, there can no more be rules for war than there can be rules for murder or rape. Worse still, it might seem that ethicists and legal theorists, in discussing the very possibility of a just or legal war, or wars fought justly, serve only to lend a veneer of legitimacy to the politicians and plutocrats who, in their vaulting ambition, drive the machine of war at the expense of countless innocents ground up underneath. 


On one view, there can no more be rules for war than there can be rules for murder or rape.


A similar worry pertains to the Law of Armed Combat, which derives from international agreements (such as the Geneva Conventions), customary international law, the conventional principles of nations, as well as case law. Though the Law of Armed Combat is complex, there are two principles undergirding many of its proscriptions. The first is that those who are not or are no longer participating in hostilities cannot be targeted. The second is that the parties to an armed conflict are constrained in the methods of warfare. Those who breach the Law of Armed Combat – especially the laws defining atrocities – might be individually accountable for war crimes and prosecuted as such. To make matters more complex, NATO has its own policies and procedures defining their ‘rule of engagement’ in war. The very existence of laws and rules governing conduct in war might seems to suggest that war is a licit activity like any other activity for which there are laws and rules, such as those governing the use of automobiles, or fireworks, or pesticides. But surely, it might be said, this is absurd. How can there be laws and rules regulating an activity that is itself criminal?


War can be, and often is, morally just.


As compelling as these arguments might be, they are mistaken. War can be, and often is, morally just. As such, laws and rules governing conduct in war are perfectly apposite. To understand why, it is necessary to begin with an admittedly abstruse issue: the meaning of the word ‘war’. It might seem strange that we should confront an issue as grave as war by first appealing to semantics. But much of the confusion surrounding the morality of war derives from a confusion about the use of words.

War ethicists have long since recognized that ‘war’ might refer to two different things. Consider, for example, the Russo-Japanese War of 1904. When we refer to that war, we might be referring to a single military conflict between Russia and Japan. But sometimes when we refer to a war we mean to single out one side in a conflict. So, we might refer to ‘Russia’s war against Japan’, or, alternatively, to ‘Japan’s war against Russia’. In this sense, the Russo-Japanese War actually consisted of two wars. The same goes for all wars. Consider World War II. It consisted of at least two wars: the Allied war against the Axis powers, and the Axis’ war against the Allied powers. Ditto for civil wars. The 1860 Civil War in the United States consisted of two wars: the North’s war against the South and the South’s war against the North.

There are, then, two senses of ‘war’: the sense that refers to the conflict as a whole, and the sense that refers to a particular side in a conflict. In colloquial discourse, we often switch between these senses without even noticing it. Once we properly disambiguate between these two senses of ‘war’, we have taken the first step toward recognizing the sense in which it is possible for a war to be morally just.

So, when we refer to the war in Ukraine, we might be referring to the war as a whole. Or, alternatively, we might be referring to either Russia’s aggression or to Ukraine's defense against that aggression. Construed the first way – as a reference to the war as whole – it does indeed resist any positive moral evaluation. The war, as a whole, is an utterly horrendous tragedy. But repair now to the second way of construing war – as a reference to a war a particular side is fighting. More specifically, consider Ukraine’s defensive war against Russia. That war is indeed morally just. The decision of the Ukrainian government and of the Ukrainian people to resort to war as a means of resisting Russian aggression is a morally just decision. This is in contrast to Russia’s morally unjust decision to wage an aggressive war against Ukraine. The upshot here is that by distinguishing the two sides in a conflict we can elucidate the sense in which both of these claims can be true: the war in Ukraine is morally unjust and Ukraine’s defensive war against Russia is morally just.

But why believe that Ukraine’s defensive war against Russia is morally just? In addressing this issue, some contemporary war ethicists abstract from the specific context of war, in order to consider the general conditions under which a resort to defensive violence might be morally just. (Jeff McMahan is the prime mover and most prolific defender of this methodology).

Take the following hypothetical case. Suppose I live in a dangerous place, rampant with murderous bandits and other folks of ill-intent. One night, on my way to a grocer, an aggressor armed with a knife corners me. He is intent on killing me for no good reason. I try reasoning with him, but my attempts fail. I offer my money, which he takes; but he is still intent on killing me. I brandish my concealed firearm, but this too fails to dissuade him. He lunges at me, and my only means of preventing my own demise is by shooting him. Presumably, in doing so, I have not committed a wrong.


These constraints aren’t the conceit of those engaged in a futile or pernicious attempt to humanize an inhuman practice.


This isn’t to say that killing the aggressor is permissible regardless of what harm he will otherwise inflict. Suppose we amend this hypothetical so that the aggressor is not intent on killing me, but instead intent on subjugating me in perpetuity. Again, if the only way to avoid this outcome is by killing him, doing so is morally just. But suppose, alternatively, he is intent solely on stealing my wallet. Even if I could kill him as a means of preventing that outcome, doing so would be morally unjust since the harm I avert is not significant enough to warrant the aggressor’s death. But if what the aggressor will otherwise do to me is bad enough, then killing him is morally just if that’s the only way to stop him.

To say that killing him is ‘morally just’ is not to say that his death is a good thing. Rather, it is to say that I did not act wrongly in killing him. That is, I did not commit murder. This is because the aggressor, through his culpable actions, forfeited his right against necessary defensive violence. We can admit that killing him is a tragic affair, but still maintain that it was a just killing in that it did not violate his rights. 

The same goes for war. The reasons why an individual can justly kill a culpable aggressor when necessary to defend her own basic freedom, are fundamentally the same as the reasons why the people of a country can justly resort to war against an aggressing state (or non-state actor) when necessary to defend themselves from wrongful subjugation. Such killings do not count as murder. Importantly, though, the killing that the aggressing side commits is indeed unjust and can indeed count, at least morally, as murder. Thus, when Russian forces kill in Ukraine, they are doing so unjustly because they are doing so in furtherance of wrongly subjugating the Ukrainian people. But when Ukrainian forces kill, they are doing so justly because they are doing so in furtherance of resisting wrongful subjugation.

This doesn’t mean, though, that any and all wars aiming at resisting wrongful subjugation will be morally just. If subjugation could be resisted through less harmful means, such as diplomatic channels, then resorting to warfare would violate what is known as the ‘necessity constraint’. There are other constraints as well. When we wage war (including defensive war) civilians are foreseeably maimed and killed, even if they are not intentionally targeted. This is euphemistically called “collateral damage”. The harms inflicted on civilians over the course of a war add up. It might turn out that the good we achieve by resisting aggression isn’t morally worth it given the carnage resulting from achieving that aim. Such a war, even if it has a just cause (such as resisting wrongful subjugation) nonetheless violates what war ethicists call ‘the proportionality constraint’. The moral here is that, in morally evaluating a war – such as Ukraine’s defensive war against Russia – we need to determine not just whether that war has a just cause, but whether the war is morally worth it – that is, whether it satisfies the proportionality constraint. If it fails to do so, waging that war is unjust even if the war has a just aim.

Supposing the just side in a war satisfies all these conditions, they might still conduct themselves badly in war, by targeting civilians, using illicit weapons, abusing prisoners of war, and so on. Those killings would be unjust. As mentioned at the outset, it might seem bizarre that there should be ‘rules’ governing conduct in war. But again, we can repair to the norms of self-defense more generally to understand the basis for these rules.

To see this, consider again the example of the culpable aggressor attempting to kill me while I’m on my way the grocer. Suppose I successfully subdue the aggressor, but then proceed to torture him. Or suppose his young child is accompanying him, and I defend myself by targeting his child, knowing that it will distract him. These tactics would not constitute a morally just means of defending myself. This is because such tactics either inflict unnecessary harm, or otherwise harm those who are not themselves threatening me. These basic precepts of defensive violence (along with others) ground the rules of war, which restrict even the parties whose resort to war is just.

We are now in a position to better understand what contemporary war ethicists mean when they claim that a given war is ‘just’. They mean that a particular side’s resort to war is morally just, and that it is fought in a morally just way. That side’s resort to war is just if it’s aim is to resist wrongful subjugation, and if there is no less harmful means of securing that aim, and if achieving that aim is worth it given the resulting carnage of war. And that side’s war is fought justly if it restricts its targets to threats from the other side and avoids unnecessary or disproportionate carnage.

These constraints aren’t the conceit of those engaged in a futile or pernicious attempt to humanize an inhuman practice. They are instead grounded in the norms of defensive violence that protect valuable goods, such as our freedom, our homes, and our lives. Such rights are so important, that the only way to forfeit them is precisely by violating those selfsame rights. This explains why necessary lethal defense against such violators does not constitute murder. 

These considerations provide a basis for the Law of Armed Conflict which governs conduct in war. In addition, these considerations suggest that there should be international procedures regulating the resort to war in the first place. For example, the United Nations has a procedure for protecting its members against unlawful aggression by authorizing the use of collective sanctions or military force against the aggressor. Unfortunately, this procedure is often victim to the institutional shortcomings of the United Nations Security Council. As a permanent member of the Security Council, the Russian Federation has veto power in such decisions and can therefore unilaterally forestall any such attempt by the UN to stymie Russia’s aggression in Ukraine. Clearly, the institutional design of this collective-action decision-procedure is fundamentally flawed; but this does not vitiate the basic moral principle that tells us aggressive, unjust wars ought to be met with collective defense. We simply need better institutional design at the international level to enforce that principle.

Much more can be said – and has been said – about war ethics. I haven’t considered the responsibility of individual combatants for the unjust wars in which they are fighting. I haven’t considered how to weigh goods and evils in evaluative whether a war satisfies the proportionality constraint. I haven’t considered the morality of preemptive wars or humanitarian wars or wars against non-state actors. Neither have I considered what justice requires after war.

Rather, my goal here has been to make sense of how and why we can – and should – uncover moral and legal norms for the most immoral of human conduct.

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