Addressing the question of whether war is a rational decision or a mistake is important to understand the causes of war and explain the reduction in the number of wars fought among countries in today’s nuclear era. The argument, under which war is a mistake, is a normative claim about what action states should have chosen, based on the outcomes that have been produced. That is, for a decision to be good, it needs to have produced the actor’s preferred outcome. However, the mistake perspective is problematic under the uncertainty and competitiveness of the anarchic international political system.
The rational theory provides a better alternative. In this paper, the rational theory of war will unfold by beginning with an understanding of states, consistent with the realist’s perspective and the expected utility theory, to be maximizing utility. This perspective will then be confronted with three different characteristics of the system, leading to a theory of states’ rationality in the form of strategic interaction. According to this theory, the reason for the reduction in the number of wars fought among countries under today’s nuclear era is caused by the nature of rational states, interested in maximizing their power under anarchy, being constrained by the relative balance of power in the system, the systemic nature of warfare and the system’s payoff structure requiring certain strategic behaviour. Firstly, the concept of mutual assured destruction has increased the costs of war and shifted the rational utility-maximizing states’ policy from winning to avoiding wars. Second, today’s ‘balanced multi polarity’, stabilized by nuclear technology, makes international relations more secure and thus less prone to wars between states now than in the past. Thirdly, the defensive nature of nuclear second strike capability prevents states from engaging in offensive military action. Finally, the structure of today’s nuclear era as the game of chicken imposes different strategic behaviour to rational states, requiring them to replace war by another instrument of states’ policy.
Rationality and the maximization of expected utility: Higher costs of war
The rising costs of war under today’s nuclear era have shifted the rational utility-maximizing states’ policy from winning to avoiding wars, thus reducing the number of wars between countries now compared to the past. Wars, according to the realist’s perspective, are fought by rational utility-maximizers states seeking to increase their relative power and security under anarchy. The realist’s notion of anarchy, “an ordering principle, which says that the system comprises independent states that have no central authority above them” (Mearsheimer 2001, p. 60) is, in itself, not sufficient to account for conflict. However, this system requires that a self-centered rational state, having no one else to rely on, must at the very least focus on its own security. Moreover, states operating under this system of...