It was the chemical weapons attack that so nearly led to direct war between the US, the UK, France and the Syrian government; a war which most likely would have delivered the whole of Syria to IS and Al-Qaeda extremists.
The recent tragedies in Colorado Springs and San Bernardino have prompted more calls for gun control. But what controls? And will they work? Gun-control advocates say we need universal background checks and bans on assault weapons and gun sales to those on the no-fly list.