[Hootowl99]

Chlorine gas is poisonous but I don't put it in the category of a WMD. It is probably the most common industrial chemical there is. The primary uses are as a raw material in plastics manufacturing and in water sanitation. For Iraq and Syria, water sanitation is going the primary and likely only use for chlorine.

All public water systems of a significant size will have ton cylinders of gaseous chlorine for maintaining the quality of the public water system and disinfection of treated wastewater. Take away the chlorine and disease such as typhus and diphtheria will become established.

[shotgun]

Chlorine gas cylinders in municipal water use are in the process of going the way of the dinosaurs because they are extremely hazardous.

They are being replaced by liquid chlorine generators either using calcium chloride tablets (water soluble solution ) sodium hypochlorite ( rock salt and electricity). The resulting chlorine product is so weak that it won’t even bleach your clothes.

[driftdiver]

When its installed in an artillery shell I would classify it as a WMD. Obviously it has other uses.