In a heated exchange with Senator Ted Cruz during a hearing earlier in the day, Mr Holder said it was not appropriate to use lethal force - "drones, be it guns or whatever else" - on a US citizen.
In fact, however intrusive or comprehensive the inspection regime developed for a chemical weapons ban might be, it will be entirely inadequate to ensure that lethal chemical agents are not covertly produced and stored wherever nations, organizations or individuals wish to do so.