To my mind, the situation in Syria has prompted an incredibly thoughtful debate within the political science community, one that undermines the idea that scholars have become irrevocably detached from policy. Ian Hurd and Charli Carpenter have written excellent pieces on the legality of chemical weapons and military intervention.  James Fearon contributed this superb piece on the strategic dilemmas involved in the US response.  And once again, The Onion has shown us all that it is the smartest game in town when it comes to foreign policy.Much of the conversation has concerned the question of interventions in civil conflicts, asking under what conditions interventions are successful and if those conditions apply in Syria. But like Jon Western and others, I’m thinking about Syria not as a case of intervention in civil conflict and more about it as a case of deterrence and compellence.

The United States has made it clear that strikes will be limited in both the extent of force applied (cruise missile strikes lasting a few days) and in its intended outcome (strikes are not intended to change the balance of power on the ground).  Reports out of the White House suggest that the Obama administration seeks both to change Assad’s behavior (to compel the abandonment of chemical weapons), as well as to deter other actors—yes, Iran, we’re looking at you—from considering similar action in the future.

We all know that coercive diplomacy is a tricky business.  To add to the myriad concerns about US strikes, I want to outline a few problems that shape the success of compellence: the problem of definitions; the problem of credible assurances; and the problem of finding room to negotiate.

First, if compellence is going to be effective, the US must be crystal clear in defining the behavior that Assad must cease.  On the face of it, this seems to be something that the Obama administration has achieved: it has gone out of its way to explain that Assad must stop using chemical weapons.  Thus “the use of chemical weapons” is the bright red line that must not be crossed.  But what seems to be a bright line is actually quite blurry.  For example, is the action to be stopped “mass killing of civilians” or “mass killing of civilians with chemical weapons”?  Moreover, given that the US did not respond to Assad’s prior use of chemical weapons, does this suggest that there is a threshold of civilians killed, that if he just uses a tiny bit of chemical weapons then strikes will not re-occur?

This brings me to a second and related point.  For compellence to be successful, there must not only be credible threats, but credible assurances as well.  Here, the US must credibly promise that if Assad does not use chemical weapons in the future, then the US will not escalate its use of military force.  Certainly the US has been reluctant to intervene in Syria, but can it promise not to intervene if, say, Assad sticks to killing lots of civilians with incendiary weapons rather than sarin?  Hardly seems the type of promise the US wants to make, or can make publicly.

Third, if compellence is going to work, there has to be space for bargaining: Syria must be willing to accept what the US is offering.  In a comment on Fearon’s post, Andy Kydd suggests that this is the case, noting that “if the goal is simply to prevent Assad from using chemical weapons to kill civilians, this is a very modest demand that does not conflict with Assad’s objectives, and so limited punishment has more of a chance of achieving it. He can simply kill them with artillery as he has been doing thus far.”  Good point, but Assad has domestic considerations that might make accepting US ultimatums unacceptable, even if it is commensurate with his interests. If it was a rogue unit that ordered the attacks, for example, attempting to stop the behavior might cause defections within the armed forces.

In short, it’s unclear that the US can offer the types of clear definitions, the credible assurances, or the deal necessary to make compellence effective.  If this is the case, the strike is more punishment for punishment’s sake than it is to achieve an end goal.