http://www.bbc.co.uk/news/world-us-canada-23842867

While a government using chemical weapons against its own people is an affront that may demand international action, it seems obvious that a far greater horror from the US point of view is those weapons being used against its own people or allies.

The great fear since the 9/11 attacks has been such weapons falling into the hands of those the West regards as terrorists.

Given that one of the main opposition groups in Syria has formally declared allegiance to al-Qaeda, that must be a real possibility.