I realize the title is counter-intuitive, but please read my reasoning.
We know that Assad always maintained control over the use of his chemical weapons, and denied repeated requests to use them near Damascus, per the German intelligence. The Germans have concluded that Assad neither ordered nor approved the use of the weapons.
If accurate, that is bad, because it means that Assad's commanders are willing to cross him. Which means that Syria is entering a post-Assad era, and the commanders are now concerned with their own fate in that new regime.
More below the Orange Squiggle of Power.
Consider Afghanistan and Iraq as examples of what happens when nations composed of many fractious tribes lose strong central authority. In Afghanistan most of the country is ruled by warlords; in Iraq, the central government has a little more control but there is still sectarian and tribal battling.
Now throw chemical weapons into the mix. Suppose you are a military commander under Assad who is in control of chemical weapons. The odds are pretty good that you have your position because you were perceived as loyal to Assad; but you see the handwriting on the wall, and you are more loyal to yourself than to him.
The odds are also pretty good that you are a ruthless bastard, as I think that's a characteristic Bashar al-Assad would value in a military commander.
So now, in post Assad Syria, you want to be a Warlord! And rule a vast domain! Are you willing to use chemical weapons to secure and expand your domain? Sure - if you can get away with it. And you also have to worry that your neighboring Warlord will if you don't.
Imagine, if you will, 5 or 10 or 20 fiefdoms, each armed with chemical weapons and ruled by a warlord willing to use them. With shifting alliances, some of these warlords are allied with extra-Syrian powers - Iran, or Al Qaeda, or Hezbollah, or Israel, or the US, or Russia, or Turkey, or Saudi Arabia, or whoever else you can imagine wanting to have a finger in that particular pie.
In a colossal clustering copulation like that, how long would it be until another mass casualty attack occurred - and then another - and then another? And the pressure would be very great for the United States to Lead the World in Doing Something.
Getting UN approval would not be the problem. Going in and getting the weapons would be a very big problem. As in Iraq, the sequel, sized problem.
For all of our sakes, I hope the diplomacy works. And if the diplomacy doesn't work, I hope Assad is in fact in control of his chemical weapons.
Because an innocent Assad might mean war, later rather than sooner, and very large rather than "incredibly small".