I agree with you totally, but the sad truth is that after suffering that dreadful chemical attack, thousands, probably tens of thousands of innocent civilians will be killed by Western or American missiles if they decide to intervene with military action. Furthermore, I've heard loads of "should we, shouldn't we" debate yet very little about the objective of such action and more importantly the end game and exit plan. If anyone thinks life for the average person in Afghanistan will improve once the troops pull out then your are deluded. The same applies to Syria, there are millions who support Assad, if he and his regime are overthrown with the help of outside forces, those people aren't going to stand around, they will form terrorist organisations, killing and bombing yet more innocents.
However difficult, the solution to this crisis must be formed, executed and implemented by the Syrian people themselves. The sad fact is that many more will die before that solution is found.