People need to understand that real-world politics is not a Hollywood movie. Strategical moves and interactions are much more complicated than the "we are the good guys and we need to kill the bad guys" narrative. I have written a post on the real motives behind the whole thing. Guess what, its all about control of the natural gas market. You might want to check it out.
RE: Repeating Lies to Wage War in Syria: Assad Was Accused of Chemical Attacks in April 2017, Still No Proof