International Security

The victims of the chemical weapons attacks in Syria have suffered immeasurably. Yet, many more have been killed and maimed by conventional weapons. Why are we so much more outraged when people are killed by chemical weapons than when they are killed in a more conventional way? Why should Assad be able to kill hundreds of thousands with conventional weapons without a U.S. military intervention but a much more modest attack using chemical weapons crosses the proverbial red line?

The answer, at the surface, is that there is a taboo on chemical weapons usage and that it is in the U.S. interest to enforce this taboo. If Syria uses chemical weapons and remains unpunished this may set a dangerous precedent. Moreover, once the U.S. has made a commitment, its own credibility would be undermined if it takes no enforcement action.

Yet, what is the rational basis for such a strong norm against chemical weapons? Some writers such as John Mueller (in Foreign Affairs), Nick Gillespie (Reason), and John Glaser have called for erasing the red line. They argue that it is not at all clear that chemical weapons when used, such as in World War I, were more hurtful to civilians or military personnel than conventional weapons. Indeed, chemical weapons could potentially make for more humane warfare given their potential to incapacitate armies without killing them.

More generally, it is not so obvious what makes chemical weapons different from other weaponry that can be used for gruesome ends. There have been countless technological revolutions in warfare that have invoked revulsion and attempted bans. For example, in 1899 all major powers agreed to a Declaration concerning the Prohibition of the Discharge of Projectiles and Explosives from Balloons or by Other New Analogous Methods. Today, projectiles are rarely discharged from balloons but “new analogous methods” have become rather popular and extremely deadly. Drones are just the latest analogous method (go read Mark Bowden’s excellent piece on how to think about drones in The Atlantic).

Richard Price offers what is perhaps the best known analysis of why the taboo on chemical weapons has stuck relatively well while other attempts at banning have failed. The argument is complex but a key point is that bans are more likely to succeed if they are grafted into pre-existing taboos. Historically, chemical weapons have been heavily associated with poison; the quintessential weapon of the weak, which undermines proper battles for political power based on physical strength. This makes chemical weapons usage easy to associate with cowardice. Price also highlights the importance of another Declaration stemming from the 1899 Hague Peace Conference: the Declaration concerning the Prohibition of the Use of Projectiles with the Sole Object to Spread Asphyxiating Poisonous Gases. To Price this early institutionalization of a ban on a chemical weapon created a pathway for outlawing others. This, of course, begs the question why the balloon Declaration failed. The instrumentalist in me suspects that the variation in outcomes may well have something to do with the fact that they never quite invented a “new analogous method” that was quite as effective as airplanes (to balloons) for asphyxiating poisonous gases.

There are other arguments too. Some highlight the military ineffectiveness of chemical weapons given that they are highly indiscriminate in who they kill, thus also creating unnecessary human suffering. Another concern is that stockpiles of chemical weapons are susceptible to be used by terrorists, other non-state actors, or weak states. It should be in the interest of the world’s most powerful states to prolong a taboo on weapons of the weak. A world with a lot of chemical weapons would be a less stable world because it is less easily controlled by states. A world without fighter jets would have the opposite implication. It may not be a coincidence that many of the writers skeptical of the chemical weapons taboo are on the libertarian end of the political spectrum or, in the case of John Mueller, have long argued that the threat of terrorism is inflated.

There are credible arguments that at least some chemical weapons create unusual human suffering that may last long after a war is over and that are difficult to predict and control. Agent orange would be an example. Yet it is difficult to make the case based on human suffering alone. There has been so much carnage in Syria already. Surely, this should have triggered a response already if this were the sole basis for our outrage. Even economists accept that repugnance may be a real and persistent constraint on behavior even if the rational basis for it is not always obvious. Questioning the rational basis for this repugnance is worthwhile when the stakes are military intervention or indeed, not intervening when the human cost in Syria have been mounting.

There is another difficult puzzle here. The U.S. and its allies would clearly prefer not to intervene militarily in Syria. By announcing the red line they essentially told Assad that he can do whatever he pleases as long as he does not use chemical weapons. Surely the optimal strategy is for the Syrian military to refrain from chemical weapons usage unless they thought these provided an overwhelming military advantage and/or they did not find the red line credible. It may be that an earlier small scale usage was an attempt to test the red line. Perhaps Assad thought that if the West is relatively unresponsive to the large number of victims due to conventional weapons, it will ultimately not make such a large distinction when chemical weapons are used given the fuzzy rational basis for the distinction. After all, it’s not like he didn’t already commit war crimes and crimes against humanity. Thoughts?

ps 1: You may also want to check out these thoughts from Stephen Walt (from April) and Kevin Jon Heller who ask a similar question (someone just pointed these out to me).