Introduction
This chapter examines what causes war between states. First, I briefly address some preliminary questions: When/why did the causes of war become important to the study of International Relations (IR)? What is at stake in this issue? Why does it matter? To whom? The next section outlines some of the major issues and debates in this subject-field of IR with reference to a few selected landmark contributions over the last several decades. The following section presents what I regard as the most useful set of concepts for analysing and understanding this topic.
Before I begin the discussion, I should clarify that, usually – and this is the practice I follow in this chapter – only those interstate armed conflicts with more than a certain number of total battle deaths are treated as ‘war’. IR scholars generally set this minimum at around 1000 in line with the ‘Correlates of War Project’ definition (Singer and Small 1972: 381). The Cuban Missile Crisis (1962), with just one ‘battle’ death – of an American U2 pilot shot down over Cuba – was clearly not ‘war’ by this definition, whereas the Falklands War (1982), resulting in about 950 battle deaths, is usually treated as ‘war’; ‘not to count it [as war because the number fell below the 1000 mark] would be splitting hairs’ (Russett 1993: 12).
Interestingly, war has not always been regarded as a problem requiring serious scholarly attention to its causes. Strange though it may now seem, some thinkers and practitioners – especially of the nineteenth century – held a benign or even positive view of war. Especially through the experience of World War I, however, a contrary view that sees war in a negative way – as a criminal act or a pathological state requiring prevention and remedy – has become dominant. Our interest in the causes of war rather than, say, heroic deeds on the battlefield is a reflection of this broad shift in our attitude towards war. Since this shift was also a key factor in the formation of IR as an academic discipline, it is unsurprising that inquiry into the causes of war has been a traditional concern of that subject (see Introduction).