An Introduction to International Relations

Introduction

This chapter provides a brief introduction to the ethics and laws of war in three parts. The first part outlines what international law and the ‘just war’ tradition have to say about recourse to force, the second section explores the conduct of war and the final section explores two recent issues as examples of moral and legal debate: the legitimacy of pre-emptive self-defence and the use of suicide car bombs.

War is an almost ubiquitous part of human history. For as long as there have been distinctive human groups, there has been organised violence – war – between them (Gat 2006). But because endemic violence between communities had detrimental effects on whole civilisations – inhibiting demographic growth, for example – many developed rules and customs to limit and control the extent of violence and determine the victors. As Ian Clark (2016), Stephen Neff and others have pointed out, ‘war’ is not just the practice of organized violence but a particular form of organized violence ordered by customs, ethics and – more recently – legal rules. Thus, although some realists argue that there is no place for morality in war – reflecting the views of the Union Army's General Sherman who, during the US Civil War, maintained that ‘war is all hell’ and the only moral course was to do everything possible to succeed – the fact is that the concept of war itself is deeply imbued with moral and legal arguments. Indeed, Sherman's argument is itself a moral argument about war. Others would go further. Those that Martin Ceadel (1987) described as ‘warists’ – among them nineteenthcentury nationalists, twentieth-century fascists and twenty-first-century jihadists – see war itself as a moral good.

Today, questions about when it is legitimate to go to war and how war must be conducted are central to public and political debates, and play a significant role in policy-making and military decision-making. Indeed, it is war's character as a rulegoverned activity that demarcates it from other forms of violence, such as raiding and terrorism. Decisions to invade countries like Iraq or Afghanistan, intervene – or not – in major civil wars such as those in Libya and Syria, participate in wars such as Vietnam and World War I, or send peacekeepers to South Sudan or Mali are only partly strategic choices.