Chemical weapons are a nightmare for Syrians

This week, the world is learning that on August 21, Syria's Assad regime attacked civilians living on the outskirts of Damascus, killing at least 355 of them, including many small children. According to Vice President Joe Biden, there is "no doubt" that chemical weapons were used by the regime -- and not, as the Assad government has claimed, by rebel forces.

The victims suffered terrible and painful deaths. Many experts are concluding that most likely a nerve agent such as sarin was deployed. Sarin is a type of organophosphate (OP), a class of chemicals used for making herbicides, insecticides and nerve gases.