Deterrence Theory - Rational Deterrence Theory

Rational Deterrence Theory

The predominant approach to theorizing about deterrence has entailed the use of rational choice and game-theoretic models of decision making (see game theory). Deterrence theorists have consistently argued that deterrence success is more likely if a defending state's deterrent threat is credible to an attacking state. Huth outlines that a threat is considered credible if the defending state possesses both the military capabilities to inflict substantial costs on an attacking state in an armed conflict, and if the attacking state believes that the defending state is resolved to use its available military forces. Huth goes on to explain the four key factors for consideration under rational deterrence theory being (i) the military balance; (ii) signaling and bargaining power; (iii) reputations for resolve; and (iv) interests at stake.

The military balance

Deterrence is often directed against state leaders who have specific territorial goals that they seek to attain either by seizing disputed territory in a limited military attack or by occupying disputed territory after the decisive defeat of the adversary's armed forces. In either case, the strategic orientation of potential attacking states is generally short term and driven by concerns about military cost and effectiveness. For successful deterrence, defending states need the military capacity to respond quickly and in strength to a range of contingencies. Where deterrence often fails is when either a defending state or an attacking state under or overestimate the others' ability to undertake a particular course of action.

Signaling and bargaining power

The central problem for a state that seeks to communicate a credible deterrent threat through diplomatic or military actions is that all defending states have an incentive to act as if they are determined to resist an attack, in the hope that the attacking state will back away from military conflict with a seemingly resolved adversary. If all defending states have such incentives, then potential attacking states may discount statements made by defending states along with any movement of military forces as merely bluffs. In this regards, rational deterrence theorists have argued that costly signals are required to communicate the credibility of a defending state's resolve. Costly signals are those actions and statements that clearly increase the risk of a military conflict and also increase the costs of backing down from a deterrent threat. States that are bluffing will be unwilling to cross a certain threshold of threat and military action for fear of committing themselves to an armed conflict.

Reputations for resolve

There are three different arguments that have been developed in relation to the role of reputations in influencing deterrence outcomes. The first argument focuses on a defending state's past behaviour in international disputes and crises, which creates strong beliefs in a potential attacking state about the defending state's expected behaviour in future conflicts. The credibilities of a defending state's policies are arguably linked over time, and reputations for resolve have a powerful causal impact on an attacking state's decision whether to challenge either general or immediate deterrence. The second approach argues that reputations have a limited impact on deterrence outcomes because the credibility of deterrence is heavily determined by the specific configuration of military capabilities, interests at stake, and political constraints faced by a defending state in a given situation of attempted deterrence. The argument of this school of thought is that potential attacking states are not likely to draw strong inferences about a defending states resolve from prior conflicts because potential attacking states do not believe that a defending state's past behaviour is a reliable predictor of future behaviour. The third approach is a middle ground between the first two approaches. It argues that potential attacking states are likely to draw reputational inferences about resolve from the past behaviour of defending states only under certain conditions. The insight is the expectation that decision makers will use only certain types of information when drawing inferences about reputations, and an attacking state updates and revises its beliefs when the unanticipated behaviour of a defending state cannot be explained by case-specific variables.

Interests at stake

Although costly signaling and bargaining power are more well established arguments in rational deterrence theory, the interests of defending states are not as well known, and attacking states may look beyond the short term bargaining tactics of a defending state and seek to determine what interests are at stake for the defending state that would justify the risks of a military conflict. The argument here is that defending states that have greater interests at stake in a dispute will be more resolved to use force and be more willing to endure military losses in order to secure those interests. Even less well established arguments are the specific interests that are more salient to state leaders such as military interests versus economic interests.

Furthermore, Huth argues that both supporters and critics of rational deterrence theory agree that an unfavourable assessment of the domestic and international status quo by state leaders can undermine or severely test the success of deterrence. In a rational choice approach, if the expected utility of not using force is reduced by a declining status quo position, then deterrence failure is more likely, since the alternative option of using force becomes relatively more attractive.