Why deplete ISIS fighting potential instead of, for example, firing one warning missile to Assad whereabouts, if US is 100% sure gas attack on civilians is done by his order?
This puts US on side of ISIS no matter which way media reports it.

So, no investigation, no respect for international law, just whatever US president with his questionable mental stability decides in his own chaotic manner.
US  attacks countries left and right whenever they find it useful, regardless who is their president, and that needs to stop somehow.

US politics is the largest destabilizer of the world and continues to decisively contribute to generation of terrorism organizations and general instability.
US has immensely benefited from it as being perceived as island of stability so capital  and brains, from the world they destabilize, continues to fly to US. 
I wonder what happens when that stops.