Paul Pillar

Threats of Force Don't Always Help

No matter how the next chapters of the Syrian chemical weapons story play out, a conclusion repeatedly being drawn from the story is that threats of military force work. Both those who have an innate fondness for the making (and executing) of such threats and the Obama administration—eager to describe its handling of the Syrian issue as a success—have their separate reasons for pushing this conclusion. Expect to hear it a lot in the coming days.

The conclusion is a simple one with intuitive appeal, flowing naturally to many people ever since as children they witnessed schoolyard bullies getting their way by threatening to beat up other kids. The sequence of events over the past month does make it appear that the threatened use of U.S. military force was a leading reason for the departures that Syria and Russia took over the past week regarding chemical weapons (although Eliot Cohen offers an interesting challenge to this view, noting other important factors that shaped the Russian and Syrian decisions). The danger of the commonly accepted conclusion comes from promoting a simple belief that “threats work” without considering all of the other reasons that lead them to work or not to work, and then to apply that belief to situations where they probably will not work. The situation most often invoked, of course, is Iran and the issue of its nuclear program. The simplistic belief about the supposed universal efficacy of threats of military force thus accentuates an already widely held and mistaken assumption that the more that Iranians fear a military attack the more likely they are to make concessions about their nuclear activities.

A large corpus of scholarly work has addressed the subject of military threats and sought-after political or diplomatic outcomes, a subject that usually comes under the heading of coercive diplomacy. This research by political scientists has not arrived at some single grand conclusion that military threats do (or don't) work. Instead, the research has concerned the numerous conditions and variables that increase or decrease the chance they will work. The political scientists have had plenty of material to examine; successful and unsuccessful examples of the use of threats can be found throughout history. This is true both of threats of armed force that never materialized and ones that did. In modern U.S. history, for example, the Vietnam War and especially the air war against North Vietnam was a large and conspicuous example of a failed attempt to use armed force to get an adversary to change its policies—in this case, to get the North Vietnamese to abandon its objective of uniting all of Vietnam under its rule.

Among the other variables that matter are whatever other pressures and constraints, besides the threatened military force, the targeted regime is experiencing. Failure to take such variables into account is a shortcoming of the frequent references to the air wars in the Balkans in the 1990s as supposedly having been successful in breaking the will of Slobodan Milošović. The references routinely ignore what else was going on at the time, such as what Croatian forces were doing on the ground in Bosnia. In Syria today, the Assad regime is engaged in an intense civil war and waging a struggle both domestically and internationally not only for its legitimacy but for its very existence. Nothing remotely resembling that is true of the government in Iran.

Of particular importance are the nature of the specific issues in dispute and what they imply for the priority that each side places on them, the determination of the target regime to maintain its stance, and how defensible that stance is internationally. Here again there is a big difference between the Syrian and Iranian situations. The Syrian regime not only possesses but also, it appears, lethally used a weapon that is the subject of a near-universal prohibition. The type of (not quite so universally prohibited) weapon that is supposedly the concern with Iran is one that Iran does not possess, has never used, and hasn't even decided to build. The Iranian program that is the focus of concern is one that the Iranians believe, strongly and correctly, they are entitled to maintain under international law and the relevant international control regimes.

An added aspect of the issue involved in the Iranian case is that to the extent there is any interest in Tehran in someday developing a nuclear weapon, probably the most important motivation would be a hope that such a weapon would help to deter foreign military attack on Iran. Threatening an attack is thus more likely to stoke than to diminish any interest in such a weapon.

Among the reasons that threats of armed force often not only do not work but may even be counterproductive—stiffening the resolve of the decision-makers on the other side—is that regimes do not like to be bullied. They are even more likely than schoolkids to push back, once they have gotten their nationalist dander up. Another, somewhat related, reason is that domestic politics are affected by such threats, with hardliners being empowered or incumbent decision-makers having to modify their policies to avoid losing out to the hardliners.