via New Scientist 
Chemical warfare is centuries old, but rapid advances in science could create deadly new weapons. We must act now
SYRIA, AD 256: Persian forces are under siege by the Romans. The attacking forces seek to tunnel under the Persian fortifications, but are met by a toxic mix of fumes from burning sulphur and bitumen. Syria, 2013: as yet unsubstantiated claims and counterclaims abound that chemical weapons have been deployed in the country.
The abhorrent effects of chemical warfare were unequivocally demonstrated during the first world war. This year, we mark the 25th anniversary of the use of chemical weapons against civilians in Halabja in northern Iraq under Saddam Hussein’s leadership.
Most governments now regard such weapons as militarily redundant, as demonstrated by their membership of the Chemical Weapons Convention (CWC), which prohibits the production and use of chemical weapons, commits them to destroying all existing stocks, and prevents reacquisition.




