Chemical weapons are weapons to be used in special war fare which is very likely to occure at any moment in this century. Wat's the need of making ya enemy and you to use less powerfull weapon ,why don't we then replace all guns with flowers .Weapons must stay weapons.
However this is an irrelevant question since the US has already been dismantling its chemical weapons programs for the past 20 years with around 89.75% already destroyed and our last 2 chemical depots scheduled to be dismantled in and around 2017. The dismantling of chemical weapons and disarmament is a slow and lengthy process and you are late to the party.
The US should not destroy their chemical weapons on the off chance they will need them. It is a bad cycle of will we need it? And if we get rid of it will another country get a bigger badder weapon? There is nothing wrong with having the weapon, just do not use it as a threat at every disagreement.