Deterrence Theory - The Concept of Deterrence

The Concept of Deterrence

The use of military threats as a means to deter international crises and war has been a central topic of international security research for decades. Research has predominantly focused on the theory of rational deterrence to analyse the conditions under which conventional deterrence is likely to succeed or fail. Alternative theories however have challenged the rational deterrence theory and have focused on organisational theory and cognitive psychology.

The concept of deterrence can be defined as the use of threats by one party to convince another party to refrain from initiating some course of action. A threat serves as a deterrent to the extent that it convinces its target not to carry out the intended action because of the costs and losses that target would incur. In international security, a policy of deterrence generally refers to threats of military retaliation directed by the leaders of one state to the leaders of another in an attempt to prevent the other state from resorting to the threat of use of military force in pursuit of its foreign policy goals.

As outlined by Huth, a policy of deterrence can fit into two broad categories being (i) preventing an armed attack against a state’s own territory (known as direct deterrence); or (ii) preventing an armed attack against another state (known as extended deterrence). Situations of direct deterrence often occur when there is a territorial dispute between neighboring states in which major powers (e.g. the United States) do not directly intervene. On the other hand, situations of extended deterrence often occur when a great power becomes involved. It is the latter than has generated the majority of interest in academic literature. Building on these two broad categories, Huth goes on to outline that deterrence policies may be implemented in response to a pressing short-term threat (known as immediate deterrence) or as strategy to prevent a military conflict or short term threat from arising (known as general deterrence).

A successful deterrence policy must be considered in not only military terms, but also in political terms. In military terms, deterrence success refers to preventing state leaders from issuing military threats and actions that escalate peacetime diplomatic and military cooperation into a crisis or militarized confrontation which threatens armed conflict and possibly war. The prevention of crises of wars however is not the only aim of deterrence. In addition, defending states must be able to resist the political and military demands of a potential attacking nation. If armed conflict is avoided at the price of diplomatic concessions to the maximum demands of the potential attacking nation under the threat of war, then it cannot be claimed that deterrence has succeeded.

Furthermore, as Jentleson et al. argue, two key sets of factors for successful deterrence are important being (i) a defending state strategy that firstly balances credible coercion and deft diplomacy consistent with the three criteria of proportionality, reciprocity and coercive credibility, and secondly minimises international and domestic constraints; and (ii) the extent of an attacking state's vulnerability as shaped by its domestic political and economic conditions. In broad terms, a state wishing to implement a strategy of deterrence is most likely to succeed if the costs of non-compliance it can impose on, and the benefits of compliance it can offer to, another state are greater than the benefits of noncompliance and the costs of compliance.

Deterrence theory holds that nuclear weapons are intended to deter other states from attacking with their nuclear weapons, through the promise of retaliation and possibly mutually assured destruction (MAD). Nuclear deterrence can also be applied to an attack by conventional forces; for example, the doctrine of massive retaliation threatened to launch US nuclear weapons in response to Soviet attacks.

In order for a nuclear deterrent to be successful, a country must preserve its ability to retaliate either by responding before its own weapons are destroyed or by ensuring a second strike capability. A nuclear deterrent is sometimes composed of a nuclear triad, as in the case of the nuclear weapons owned by the United States, Russia and the People's Republic of China. Other countries, such as the United Kingdom and France, have only sea-based and air-based nuclear weapons.

Proportionality

Jentleson et al. provide further detail in relation to these factors. Firstly, proportionality refers to the relationship between the defending state's scope and nature of the objectives being pursued, and the instruments available for use to pursue this. The more the defending state demands of another state, the higher that state's costs of compliance and the greater need for the defending state’s strategy to increase the costs of noncompliance and the benefits of compliance. This is a challenge, as deterrence is, by definition, a strategy of limited means. George (1991) goes on to explain that deterrence may, but is not required to, go beyond threats to the actual use of military force; but if force is actually used, it must be limited and fall short of full scale use or war otherwise it fails. The main source of disproportionality is an objective that goes beyond policy change to regime change. This has been seen in the cases of Libya, Iraq and North Korea where defending states have sought to change the leadership of a state in addition to policy changes relating primarily to their nuclear weapons programs.

Reciprocity

Secondly, Jentleson et al. outline that reciprocity involves an explicit understanding of linkage between the defending state's carrots and the attacking state's concessions. The balance lies neither in offering too little too late or for too much in return, not offering too much too soon or for too little return.

Coercive credibility

Finally, coercive credibility requires that, in addition to calculations about costs and benefits of cooperation, the defending state convincingly conveys to the attacking state that non-cooperation has consequences. Threats, uses of force, and other coercive instruments (such as economic sanctions) must be sufficiently credible in order to raise the attacking state's perceived costs of noncompliance. A defending state having a superior military capability or economic strength in itself is not enough to ensure credibility. Indeed, all three elements of a balanced deterrence strategy are more likely to be achieved if other major international actors (for example the United Nations or NATO) are supportive and if opposition within the defending state's domestic politics is limited.

The other important consideration outlined by Jentleson et al. that must taken into consideration is the domestic political and economic conditions within the attacking state affecting its vulnerability to deterrence policies, and the attacking state's ability to compensate unfavourable power balances. The first factor is whether internal political support and regime security are better served by defiance, or if there are domestic political gains to be made from improving relations with the defending state. The second factor is an economic calculation of the costs that military force, sanctions, and other coercive instruments can impose, and the benefits that trade and other economic incentives may carry. This in part is a function of the strength and flexibility of the attacking state's domestic economy and its capacity to absorb or counter the costs being imposed. The third factor is the role of elites and other key domestic political figures within the attacking state. To the extent these actors' interests are threatened with the defending state's demands, they will act to prevent or block the defending state's demands.