In less than one month -- the blink of an eye in international diplomacy -- Syrian president Bashar al-Assad has apparently agreed to verifiably disarm his country of some 1,000 metric tons of chemical weapons. This strategic capability was developed and improved upon over more than four decades and has been employed perhaps two-dozen times against the armed opposition and civilians during the current civil war. The remarkable and rapid transformation of the Assad regime's stance -- from refusing to acknowledge that it had chemical weapons, to allowing international inspectors to secure and remove them -- occurred after President Barack Obama's Aug. 31 pledge to "take military action against Syrian regime targets." Consequently, it has become a near unanimous matter of faith among U.S. officials and foreign-policy watchers that Assad gave up his chemical weapons arsenal only because of the credible threat of military force.
This is misleading, primarily because it is unknown what role contemporaneous negative and positive inducements from Russia or Iran might have played on Assad's decision-making. It also fails to consider that Assad may have cannily concluded that, given the overwhelming international opposition to his use of poison gases, disarming himself of one military capability (of limited battlefield utility) made his survival as the leader of Syria more likely, if not assured.
Accurately addressing the question of whether military coercion "worked" in Syria is vitally important, in particular because it has implications for how the United States and its partners proceed with their (suddenly accelerated) diplomatic negotiations with Iran over its nuclear program. To do so, it is useful to review what coercive diplomacy actually consists of and what its potential shortcomings are. This review reveals that, given its costs and risks, coercive diplomacy remains a tool to be used sparingly and only in concert with an array of inducements.
Coercive diplomacy, or compellence, is the threat or limited use of force to stop an adversary from doing something or undertake some material change that it otherwise would not have. The coercing state usually makes its demand with a specific deadline or some sense of urgency. Deterrence, on the other hand, attempts to persuade an adversary from taking some action by threatening something that it values. The deterring state often makes its demand with less specificity and over a more open-ended time frame; economist Thomas Schelling characterized this as "we can wait -- preferably forever; that's our purpose."
Much like debates about the role of credibility in international relations, there is something of an academic-policy gap about the utility of coercive diplomacy. Scholars have concluded that it has limited success as a policy tool. Barry Blechman and Stephen Kaplan determined that in 37 attempts between 1946 and 1975 in which U.S. armed forces attempted to influence another country's behavior through non-kinetic deployments, compellence over the long-term (three years or more) succeeded only 19 percent of the time. Meanwhile, international relations scholars Alexander George (examining seven in-depth cases) and Robert Art (22 cases) have independently found that U.S. coercive diplomacy efforts succeeded roughly 30 percent of the time.
Finally, Professor Todd Sechser recently compiled the Militarized Compellent Threats dataset, containing 210 interstate compellent threats between the end of World War I and 2001. "Overall, challengers achieved full compliance in 87 of the 210 compellent threat episodes (41.4%)," Sechser found. He also warned of the "Goliath's curse," where having military superiority -- as the United States does -- can actually reduce the effectiveness of compellent threats, since the weaker targeted state, fearing a coercing state will make even greater demands in the future, will fight costly wars sooner in order to deter aggression later.
These numbers should be viewed with some skepticism, since evaluating coercive diplomacy outcomes is difficult and subjective. Consider the debate about why Libya's Muammar al-Qaddafi gave up his fledgling uranium enrichment program and most of his chemical weapons in 2003. Academics Bruce Jentleson and Christopher Whytock argued, "U.S. credibility on the use of force was a factor," though "probably not the most important one," with Western intelligence penetration of Libya's weapons programs and the effect of multilateral sanctions on domestic politics in Libya having a greater impact. Members of the George W. Bush administration, however, incorrectly focused only on the demonstration effect of coercive regime change in Iraq. Former Vice President Dick Cheney claimed Qaddafi's concessions were "one of the great by-products ... of what we did in Iraq and Afghanistan," noting that just "five days after we captured Saddam Hussein ... Qaddafi came forward and announced that he was going to surrender all of his nuclear materials to the United States."
It is also revealing to contrast how U.S. officials embrace the use of coercion for their own objectives, while condemning its use by others. In the East China Sea and South China Sea territorial disputes, Washington consistently tells Beijing that it must solely rely upon a rules-based diplomatic approach. Secretary of Defense Chuck Hagel declared at the Shangri-La Dialogue in Singapore earlier this year, "The United States stands firmly against any coercive attempts to alter the status quo." Similarly, Hagel's deputy, Ashton Carter, noted in reference to the Asia-Pacific, "We oppose provocation. We oppose coercion. We oppose the use of force," adding a U.S. preference for "peaceful resolution of disputes in a manner consistent with international law." Of course, resorting to coercion and the use of force to change the status quo are defining characteristics of U.S. foreign policy, and -- as the reactions to Syria demonstrate -- they are widely embraced among pundits and officials. The defining questions of East Asian relations in the coming decades is whether China emulates the U.S. military by embracing coercion, or follows U.S. guidelines as to how local disputes should be resolved.
While running for president in 2008, then-Senator Hillary Clinton repeatedly justified her 2002 vote authorizing the use of force to threaten the removal of Saddam Hussein from power by proclaiming, "I believe in coercive diplomacy.... We have used the threat of force to try to make somebody change their behavior." Clinton then added, "What no one could have fully appreciated is how obsessed this president was with this particular mission."
Therein lies the great risk of coercive diplomacy: The coercing state publicly demands that another state change its behavior -- a strategy that fails most of the time. Then, with its reputation on the line, the coercing state can back down, as Obama has done recently, or plunge headlong into war, as Bush did in 2003.
This risk is worth bearing in mind as one of the longest coercive diplomacy experiments in the world continues to play out: The United States and Israel are demanding that Iran abandon or accept significant restrictions on its uranium-enrichment and plutonium-producing facilities, or else face a military attack. If Iran actually believes that this is the final demand that outside military powers will make, it might accept verifiable limits on its nuclear program. Or, having learned from the coercive regime changes in Afghanistan, Iraq, and Libya, it might just flatly refuse.