The only precedent for this is the disastrous Iraq war where the reason for the invasion was given as disarming Saddam of Weapons of Mass Destruction he turned out not to have. Most countries would therefore be justified in being skeptical of any country claiming the right to disarm another of WMD. Additionally when this is done by the major powers the action is likely to be seen as being hypocritical. In the case of Chemical Weapons the United States does not have a particularly clean record. The United States used less deadly chemical weapons, Agent Orange, in Vietnam in order to clear foliage, and in Iraq it used white phosphorus as an incendiary weapon. The United States has so far failed to decommission its own Chemical Weapons and instead keeps getting extensions. [1] Similarly both Russia and the United States had Biological Weapons programs, and although these have ended still maintain large smallpox supplies.  [1] Monbiot, George, ‘Obama’s Rogue State’, monbiot.com, 9 September 2013,