According to the United Nations, the Syrian civil war has already claimed over 60,000 lives. Yet it is not these deaths -- however tragic -- but rather the use of chemical weapons that the United States has identified as the threshold beyond which the Syrian regime's conduct will become intolerable. "The use of chemical weapons is and would be totally unacceptable," President Barack Obama said, addressing Syrian President Bashar al-Assad, on December 3, 2012. "If you make the tragic mistake of using these weapons, there will be consequences and you will be held accountable." The same day, Secretary of State Hillary Clinton sounded similarly grave warnings, stating that the use of chemical weapons "is a red line for the United States."
Now, with reports surfacing that the Syrian regime may have used a substance known as Agent 15 (a hallucinogenic chemical) in an attack last December, it is worth examining why countries such as the United States have singled out the use of chemical weapons as uniquely intolerable -- and what it will mean if Washington does not live up to its word and respond to Assad's attack with serious countermeasures.
Some history is in order. The Chemical Weapons Convention (CWC), which came into force in 1997, prohibits not only the use of chemical weapons but also their production, possession, and transfer. With the support of 188 states around the world, the CWC is one of the most widely adhered-to international treaties, and it has come to symbolize the idea that it is possible to "civilize" the conduct of war -- seemingly against all odds. The CWC marked the culmination of over a century of diplomacy condemning chemical weapons, and, as time has gone by, the use and even the possession of such weapons have become an international taboo. This tradition underpins Clinton's recent statement that the Assad regime's "behavior is reprehensible; their actions against their own people have been tragic," she continued, "But there is no doubt that there's a line between even the horrors that