Real evidence of chemical weapons use - the red line that keeps smearing? I'd be amazed if there really was any use. Syria does have nerve agents - same as Iraq. But I don't see Assad as arrogant enough to use them like Hussein did. Perhaps a local commander panicked or wanted to play messiah, but I'd be fairly surprised at that. I don't have much doubt that CWs were used - either by Assad or even by a rogue military operation.
But Obama has not made any convincing case that this is qualitatively different than, say, the Jinjaweed (Arab militia) killing a far greater # in the Sudan.....or the machete-wielding killers in Africa who have killed even more. What I find amazing is the possibility that the Senate will likely pass this. Barack Obama refuses to own any problem he creates or exacerbates - he needs to own this.