It was beginning to look like the Syrian civil war would end in a permanent stalemate. The Economist predicted the country would be functionally be divided in 3. The Alawites taking the belt from Damascus to Aleppo and west to the coast. The rebels controlling the Euphrates valley, and the Kurds their North East portion. Such a result might be viable as the many 3rd parties to the affair could maintain their interests at a relatively low price. Nobody would win, but nobody would lose either.
However, that assumes no game changers. The apparent chemical attacks this week near Damascus could be such a game changer. Somewhere there is a red line, and Assad may have just crossed it.
Chemical weapons have not been used widely since they were banned after WW1. Expensive, finicky, subject to wild swings in efficacy due to weather, and just as dangerous to the attackers as the defenders, chemical weapons have been more trouble than they were worth. It's simply too difficult to get a reliable tactical advantage on the battlefield sufficient to outweigh the political costs. Those political costs are based on the terror chemical weapons inspire in civilians.
Assad seems to have found a way to use them as a poor man's nuke. Lobbing chemical weapons into opposition neighborhoods overcomes the tactical disadvantages. If they are ineffective due to weather, its no loss. The distance between your forces and the targets will be sufficient to avoid exposure if the wind blows the wrong way. There is no effective counter-measure for the rebels. Though their usefulness is limited to terrorizing civilians.
But there is a political cost. At some point, after some red line, the International Community will put aside their differences and squash the Assad regime as a common threat. Last year, the Russians let it be known that they strongly opposed the use of chemical weapons in Syria. Their current rhetoric insists not that its OK to use the weapons, but absent conclusive proof, they have not been used at all. Widespread and blatant use by Assad would render that position untenible. In the big picture, Assad is not an essential asset to the Russians. They will throw him to the wolves if it suits them. Iran will still be there, but Iran cannot stop the Western powers if they decide to intervene.
All this means that Assad can go too far and lose everything. As of today, it looks like the red line has been found.
