While those,who want to bomb are pointing to UN REPORT indication probability of Syrian government responsibility, nobody is explaining why no rebel fighters were among the casualties. If it were a government attack the rebels would have been the target. But, if it were a jihadist attack, the killing of civilians would fit their normal MO... As seen in the marketplace, mosque and other terrorist attacks. Makes sense fir them to stage a sarin attack on civilians to use for the propaganda value against Assad.
In the USA, Syria is a Machiavellian scheme situation -- if we attack Assad, that makes the Rebel victory the result of American actions... they owe us an it will be hard for the Jihadist forces to turn the true Syrian populist rebels against us. The Republicans know that, if we refuse to help, when the rebels win they will attribute it to the majority Jihadist force among the rebels -- that allows the Jihadist elements to rally the people against America ... thus ensuring widespread war... First in Lebanon, and against Turkey ... with eventual attacks on Israel -- when Egypt is stable enough to join in.
The second part of the scheme is to nominate Ted Cruz for President in 2016. This will precipitate a Constitutional Crisis in which the candidate is undeniably a Canadian by birth, who spent the first four years of his life as a Canadian citizen. The specific language of the Constitutional qualification clause will come into play if Cruz is either the Presidential, or vice-Presidential, candidate (or worse, nominee elect). That could paralyze the "Commander-in-Chief" position long enough to ensure an opening for the Jihadists to wage their war.