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The ethics of war

DOI: 10.4324/9780415249126-L166-1
Version: v1,  Published online: 2021
Retrieved July 24, 2024, from

Article Summary

Philosophical work on the ethics of war is often labelled ‘just war theory’. Despite the label, there is no single accepted theory of when and how one can justifiably wage war. Rather, there is substantial disagreement amongst just war theorists about when and how wars may be fought. And, despite talk of ‘just’ wars, actual wars are, at best, justified rather than just. Many of the people who suffer harms in war have done nothing to lose their usual rights against being harmed. Whilst a person’s rights against harm can be justifiably infringed when doing so is necessary for avoiding a greater evil, it is still unjust that they suffer this harm (unlike, for example, if a person suffers a punishment that they deserve). When someone is justifiably made to suffer an unjust harm, they are plausibly owed compensation.

Most work on the ethics of war distinguishes between moral principles governing the justice of the war overall (jus ad bellum) and moral principles governing the conduct of war (jus in bello). Whilst there is broad consensus on at least some of the formal ad bellum and in bello criteria, there is considerable disagreement about their substantive content. For example, it is widely agreed that, to be justified, war must be a proportionate means of pursuing a just cause, but there is little disagreement about what counts as a just cause, and how to judge whether a degree of force is proportionate to that just cause.

Other disagreements concern our theoretical approaches to war – in particular, whether war is morally extraordinary, and thus cannot be judged by the moral rules that govern the use of force in other, more domestic contexts. Further key debates concern the relationship between jus ad bellum and jus in bello – for example, whether those whose war is ad bellum unjustified can satisfy the in bello conditions. This in turn bears on the moral standing of combatants who are fighting an ad bellum unjust war. There is also significant disagreement about the extent to which civilians are liable to attack in war.

Ethical issues that arise in the aftermath of war, such as reparations and punishment, fall within the scope of jus post bellum. Jus post bellum has three central concerns: (i) constraining the wrongdoing of victors, (ii) facilitating post-war reconstruction, and (iii) securing lasting peace.

Citing this article:
Frowe, Helen. The ethics of war, 2021, doi:10.4324/9780415249126-L166-1. Routledge Encyclopedia of Philosophy, Taylor and Francis,
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