Today, on the tenth day after the horrific massacre of more than 1000 innocent civilians in the Syrian civil war, the President of the United States confirmed that a powerful case has now been made that the Syrian government under President Bashar al-Assad was responsible for this attack against his own people:
Our intelligence shows the Assad regime and its forces preparing to use chemical weapons, launching rockets in the highly populated suburbs of Damascus, and acknowledging that a chemical weapons attack took place. And all of this corroborates what the world can plainly see -- hospitals overflowing with victims; terrible images of the dead. All told, well over 1,000 people were murdered. Several hundred of them were children -- young girls and boys gassed to death by their own government. This attack is an assault on human dignity.
It also presents a serious danger to our national security. It risks making a mockery of the global prohibition on the use of chemical weapons. It endangers our friends and our partners along Syria’s borders, including Israel, Jordan, Turkey, Lebanon and Iraq. It could lead to escalating use of chemical weapons, or their proliferation to terrorist groups who would do our people harm. In a world with many dangers, this menace must be confronted.
The President explained that the action that he proposes to be taken -- in response to this violation of the universal norm against the use of chemical weapons – is to be limited, both in scope and in duration.
Confident that the Assad regime can be he held accountable for this ghastly deployment of deadly gas against its own citizens, he believes that our own national security interests compel the deterrence of this kind of behavior by degrading the capacity of the regime to carry it out.
The President added that because the Chairman of the Joint Chiefs of Staff – the senior leaders of the armed forces in the Department of Defense who advice the President – assured him that such a mission will be effective “tomorrow, or next week, or one month from now,” he will also seek the authorization of the Congress:
I’ve told you what I believe, that our security and our values demand that we cannot turn away from the massacre of countless civilians with chemical weapons. And our democracy is stronger when the President and the people’s representatives stand together.
The Universal Norm Against the Use of Chemical Weapons
Another aspect of this situation are Syria's responsibilities under the instrument signed on 17 December 1968 and deposited with the respresentative of the United Nations.
There is a brief summary of the history of the Geneva Protocol -- (officially, the "Geneva Protocol
Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or other Gases, and of Bacteriological Methods of Warfare"] -- in the Wikipedia entry:
The Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or other Gases, and of Bacteriological Methods of Warfare, usually called the Geneva Protocol, is a treaty prohibiting the first use of chemical and biological weapons. It was signed at Geneva on 17 June 1925 and entered into force on 8 February 1928. It was registered in League of Nations Treaty Series on 7 September 1929. The Geneva Protocol is a protocol to the Hague Conventions of 1899 and 1907.
It prohibits the use of "asphyxiating, poisonous or other gases, and of all analogous liquids, materials or devices" and "bacteriological methods of warfare". This is now understood to be a general prohibition on chemical weapons and biological weapons, but has nothing to say about production, storage or transfer. Later treaties did cover these aspects — the 1972 Biological Weapons Convention (BWC) and the 1993 Chemical Weapons Convention (CWC). ...
The main elements of the protocol are now considered by many to be part of customary international law.
In his book, "The Chemical Weapons Taboo," Richard Price provides an interesting analysis of various treaties on point – including the backstories in the struggles to ‘get to yes,’ as the Mediators say; and Price also takes a look at political choices, over time. There is also an interesting discussion about weapons that are used characteristically by those traditionally less powerful. See this brief summary of his treatise here.