The unfettered use of chemical weapons or other WMD in the Middle-East or anywhere else is a threat to every civilised nation's interests. Now that hasn't happened yet but since Obama made the use of CW a red-line, one might argue that allowing this incident to go unpunished makes the scenario above more likely.
you mean in the same way that Israel do not allow UN inspections of their nuclear capabilities and are not signed up to the non proliferation treaties thus making them a threat to civilised nations, or is that different because the US carry a veto that will protect Israeli interests.
You can't have a rule book that you like to throw around if you casually forget about it when it does not suit.
There are a lot of people spouting media populist propaganda without really understanding that region at all.
I know I am grinding on Israel a lot, but they really are a case in point of why there is such distrust of the west with reagards to middle east policy and involvement.