Syrian Rebels who are made up of many mercenary extremist Muslim groups - Al Nusra, Muslim Brotherhood, Al Qaeda and others, fire poisonous gas on civilians and blame it on Assad. Same dirty game was played in Libya. Using these lies the US/UN/France/UK/Qatar bombs and destroys Libya. Being unsuccessful at taking over Syria by funding, arming and sending al Qaeda mercenaries in to fight they now must take drastic means to justify attacking Syria. This has to do with stopping the gas pipeline through Syria to Russia.