I find the chemical weapon definition to mitigate this issue ironic because it reminds me of the right grilling someone over sexual relations.
A weapon is only used in combat, really? So a gun is not a killing weapon unless it did so in combat. So a POW would not deserve a Purple Heart or any other military benefit extended to combat duty if their injury was due to getting shot/wounded/mutilated while a prisoner??? Next do we need to decide if combat is only when there is a declared war?