Yes, there is a "Wag the dog" smell about this, but an attack of this size doesn't happen overnight. Lots of conference table and intelligence consulting happened, before this was greenlighted and it likely has been sitting on the shelf waiting for the proper atrocity to justify it, like the whole GWOT assembled by the PNAC. Well, they're baaack. At this point the possibility that the gas attack was a false flag is at least as plausible as Assad doing this. Qui bono? Assad was winning, and had no reason to bomb his own people and lose credibility. Remember Bush's fabricated WMDs? They've done it before, and got away with it.