Bashar Assad almost certainly crossed a 'red line' by using sarin or some other chemical weapon against his own people, President Obama said in April. The casualty toll from the latest suspected use suggests sarin henceforth will be associated with Syria and Mr. Assad.
The OPCW inspectors were investigating recent claims that the Syrian regime used chlorine gas on a rebel-held town. Although the chemical is not outright banned, its use in weapons is.
The international effort to destroy Syria's chemical weapons stockpile is unprecedented for its tight deadline and dangerous security situation.
Iraq is the only other country that has been forced to surrender its chemical weapons.
President Obama is willing to push for a deal in which the international community would verifiably secure Syria's chemical weapons. That course will be difficult to pursue. But it is doable. Here's what's required.