Coercive diplomacy is based on achieving political objectives and fostering a state’s national interest without waging war. It is essentially a diplomatic strategy, one that relies on the threat of force rather than the use of force. If force must be used to strengthen diplomatic efforts at persuasion, it is employed in an exemplary manner, in the form of quite limited military action, to demonstrate resolution and willingness to escalate to high levels of military action if necessary.
‘You can claim to be really successful not when you obtain one hundred victories in one hundred battles, rather when you seize your enemy without even fighting’. This was quoted by Sun Tzu summarizing perfectly the meaning and the aim of coercive diplomacy, that is to make an enemy stop or undo an action without resorting to military action, but through issuing a specific demand backed by a threat of punishment for non-compliance with it. Clearly, the threat must be credible and potent enough to persuade the opponent that it is in his interest to comply with the demand. A state can coerce its adversary threatening political consequences, such as the expulsion from an international organization, economic sanctions, such as an embargo and the suspension of an economic agreement, or the use of force. It should be remarked that coercive diplomacy offers an alternative to reliance on military action; it is based on the threat of force rather than the use of force to get other actors to comply with one’s wishes. If force is used at all, it takes the form of an exemplary or symbolic use of military action, to demonstrate motivation and resolution to escalate to high levels of military action if necessary. Hence, in coercive diplomacy, force is not employed as part of conventional military strategy, but as a component of a political-diplomatic strategy aimed at persuading the adversary to back down. It is a more flexible, psychological instrument in contrast to the ‘physical, quick and decisive’ use made in military strategy. Furthermore, the threat and use of force in coercive diplomacy is coupled with clear communication, signaling and bargaining to make the opponent aware of one’s intentions, motivation and credibility at every step of the ongoing crisis.
Interestingly, the notion of coercive diplomacy can be distinguished by other related concepts. First, coercive diplomacy is regarded as a defensive strategy, thus distinct from blackmail – an offensive strategy – which occurs when a threat is employed to coerce a subject to give up something of value without putting up resistance. Coercive diplomacy has also to be distinguished from deterrence, i.e. a strategy that makes use of threats to dissuade an opponent from undertaking an encroachment of one’s interests not yet initiated. On the contrary, coercive diplomacy is directed at stopping an action already undertaken. The term compellance (strategy that employs threats to make an opponent stop an action already undertaken) is often used to encompass coercive diplomacy as well. George and Simons, however, suggest a difference between the two concepts, arguing that the use of “compellance” entails an exclusive reliance on military threats to wear down the enemy’s resistance. Rather, states employing coercive diplomacy have a broader range of threats to employ and, above all, may couple threats of punishment with positive inducements and assurances to influence the adversary; this variant of coercive diplomacy is referred to as “carrot and stick” approach. This was famously employed by Kennedy in the Cuban Missiles Crisis, unlike, for example, Bush in the First Gulf War.
The strategy of coercive diplomacy can take a variety of forms and pursue very different objectives. At the extremes of the spectrum of available strategies are the “try-and-see” approach and the ultimatum. The former occurs when the coercing power takes one threatening step at a time, waiting for the reaction of the adversary before making additional threats. This strategy avoids putting pressure on the counterpart and, thus, prevents the crisis from escalating sharply. The latter consists in making a specific and detailed request backed by a rigid time limit. The conditions included in the ultimatum are presented as final and require unconditional and categorical acceptance by the opponent. The terms of compliance can range from several days to only a few hours: for instance, the Italian ultimatum to the Ottoman Empire in 1911, regarding the surrender of Libya, had a deadline of twenty-four hours, while the U.S. ultimatum to Germany in 1916 demanded compliance ‘immediately’.
A state employing coercive diplomacy can achieve a wide range of objectives. The most limited one is to make the enemy stop an action already undertaken; a more ambitious one is the reversal of what has been already accomplished, namely the opponent is forced not only to stop its enterprise, but also to give up the advantages that its action had previously gained; finally, the most difficult one, as Bruce Jentleson notes, is the cessation of the opponent’s hostile behaviour through a change in the composition of his government or the regime.
Coercive diplomacy is an attractive strategy because it offers the possibility of achieving political objectives without resorting to the use of traditional military force, with less bloodshed and political costs. In the history of international conflict, it has proved to be particularly efficient to intimidate, with little risk and weaker adversaries. Nevertheless, it is also a dangerous option as it can backfire, quicken the escalation and lead to an unanticipated war. This happens when the coercing power boxes into the corner a highly motivated adversary which is inclined to escalate the crisis to avoid a humiliating defeat. Moreover, the opponent can reject the request thinking it is a bluff, and challenge the coercing power, especially in the case of ultimatum. Thus, two key-variables of coercive diplomacy are the magnitude of the demand made on the opponent and his motivation not to comply with it; these two variables are strictly connected as the strength of the adversary’s reluctance to comply with the request is deeply sensitive to the magnitude of the request advanced by the coercing power.
Overall, it is possible to identify several conditions that favour the successful use of coercive diplomacy in a dispute between two states such as: clarity of the objective, efficient communication of intentions and signaling of interests at stake and unilateral coercive diplomacy. A key-variable that underpins these is a balance of power in favour of the coercing state: its availability of massive material capabilities is more likely to persuade the counterpart to back off, as it will perceive the threat as sufficiently credible and potent. These conditions rest on the assumption of a “rational” opponent, who correctly evaluates whether the danger and risks of not complying outweigh the costs and gains to be expected from yielding to the demand of the coercing power.
In front of the Soviet deployment of medium-range ballistic missiles in Cuba, President Kennedy decided to avoid the option of military intervention and adopted coercive diplomacy ordering a naval blockade that, in his intentions, would demonstrate his strong resolution to order an invasion of Cuba and induce Khrushchev to remove the missiles. The U.S. President adopted a “try-and-see” approach as he slowed the implementation of the naval blockade and of the build-up of military forces, waiting for the reaction of the opponent. Throughout the crisis, both Kennedy and Khrushchev adhered to strict principles of crisis management and gave clear signaling of their interests at stake and their preference for a peaceful settlement of the crisis. Following dramatic events that could potentially lead to war, such as the shooting down of a US U-2 spy plane over Cuba, Kennedy decided to exert a stronger pressure on the USSR, conveying the equivalent of an ultimatum to the Soviet Ambassador; at the same time, however, he adopted a “carrot and stick” approach accepting in secret the removal of U.S. Jupiter missiles from Turkey. Khrushchev accepted Kennedy’s formula and put an end to the crisis. The strategic environment and the policies of both leaders made the use of coercive diplomacy possible in this case. On the one hand, Kennedy limited his objective and the means he employed on its behalf. He gave the Soviet leader enough time to evaluate costs and risks of non-compliance and coupled his threats with positive inducements. On the other hand, Khrushchev clearly understood the asymmetry of interest in favour of the United States and its resolution to achieve its objective: it was more important to the United States to remove the missiles from Cuba than it was to the USSR to keep them there. Thus, he backed off accepting the quid pro quo before the crisis escalated to war.
A second case study using coercive diplomacy is the First Gulf War. After the Iraqi invasion of Kuwait in August 1990, the USA summoned Saddam Hussein to back off. The USA, together with the UN, took all the steps deemed necessary in order to make their threats credible: they were successful in constructing an economic embargo and in putting together a massive coalition of thirty-five states; U.S. President Bush deployed military forces to Saudi Arabia and, in October, threatened the use of force against Iraq; finally, in November, U.N. Resolution 678 issued an ultimatum which called on Iraq to comply with the request of withdrawal from Kuwait by 15th January 1991. Notwithstanding all these measures, Saddam refused to comply and Iraqi troops retreated from Kuwait only after being defeated in a ground military campaign in February 1991. Different reasons can account for the failure of coercive diplomacy in this case. Even though the U.S. and the UN gave clear signaling of their intentions since early August, their threats were not considered to be credible by Saddam: he underestimated the international resistance that annexing Kuwait would generate and believed that even if the USA embarked on a war, it would not be able to sustain domestic support in case of heavy casualties suffered by U.S. troops. He was also convinced that, in case of war, all the Arab countries would come to his support against the American enemy. Furthermore, Saddam’s motivation and interests at stake were extremely high in the dispute: he had depicted Iraq as the emerging Middle Eastern power after the end of the Cold War and himself as the undisputed Arab leader; backing off in front of U.S. threats would have irreparably damaged his public image as champion of Arab interests. He believed that the risks to his personal power from surrender without fighting outweighed the risks of defeat in war; accordingly, he decided not to back off and escalated the crisis to war.
In conclusion, the practice of coercive diplomacy is widely employed by states in the international system as it proves to be a viable means to achieve political objectives without resorting to war, which is costly also for the winner. However, its successful use is conditional to a favorable strategic environment and to the presence of several circumstances for the coercing power.