Considering the ambiguities of the evidence so far, the controversy over allegations that chemical weapons were used in Syria, much of the political posturing seems premature. The issue came up on President Obama's first day in Israel, with the Israelis saying they are convinced that chemical weapons were used. The trouble is, there isn't much evidence.
Though most Western reporting has focused on the assumption that the Asad regime was behind the alleged chemical use, it was the Asad regime that first reported the claim, blaming rebel forces. The most publicized video also shows victims in a government hospital. Now each side is blaming the other, but why would the regime have made the first charge? Possibly to justify a retaliatory use?
But what chemical weapon was allegedly used? Questions are being asked but not really answered. The video shows people in a hospital in masks, and some on respirators, and complaining of pain in the chest. But there is no visible burning of the skin as many chemical weapons would produce, and the results do not look like highly lethal nerve agents were used.
The coincidence of these allegations with the 10th anniversary of the Iraq war, launched to stop weapons of mass destruction that weren't present, should be an added reason for caution in such an ambiguous situation.
The recent rebel victory in the city of Raqqa, giving them control of their first major city and first full province (though they control much of Idlib province as well), (see also here), could be seen as s turning point for the war, and the regime could be feeling cornered and ready to use chemical weapons. But the evidence for that is by no means in.