also it's total nonsense to state that if Assad had quickly been removed Isil would be running the whole country. You have absolutely no idea whether that is true or not and frankly I do not believe it one bit. They exploited a vacuum. If there had been another quickly appointed administration with forces backing then Syrias fall would have been no more likely than jordans now
I just don't know how much more evidence you need.
I'm far from sure you believe it yourself hence your big use of the word "if" on two absolutely essential points, neither of which you could likely deliver. I'll deal with the military though rather than trying to find a credible alternative leadership
The officer corps of the Syrain military are hand picked loyalists to the Assad dynatsy and could be relied on to fight.
OK, what do you think happens to this group (the military) when they suddenly have some Professor from Damascus university imposed on them as their new leader? or as is more likely, an ex-emigre.
Remember they lose a fair amount of their status and their 'buy in' when Assad is toppled. Are they still willing to go out and fight and risk death for this new regime which has disenfranchised them by it's very existance and imposition? I know you prefer to simply blunder into things without assessing the evidence, and then try and spin your way out of a hole, but in your silly world of unicorns and pixies, do you expect the degraded officer corps of the army to unswervingly answer this new administration? Have you learnt nothing from what happened in Iraq and Libya?.
Those who stay loyal to the concept of government, will be a reduced body of men. Others will melt away back into society, whereas others will take up arms in support of the various militia groups that such a vacuum would form (the Saddamists are an example of this happening elsewhere of course if you want evidence). Which ever way you look at it, the Syrian state military (already struggling) would be a degraded fighting force
Who exactly do you think is carrying the fight to ISIL at the moment Clive? If the Syrian military stopped fighting tomorrow what do you honestly think would happen? Or are you seriosuly suggesting that ISIL would then disband and liberal democracy would breakout and everyone lives happily ever after. This is pink castles in the sky and mermaid territory. ISIL would march straight on Damascus, pronounce an expansion of the caliphate and enslave and kill anyone of whom they disapproved
I'm afraid what you're guilty of Clive is picking out a 100% idealist end game, and then trying to back fit and agreeable narrative over the top of it to suit your own personal opinion. You're wantonly ignoring for reasons of dogma all the unfortunate pragmatic objections that you encounter on the way, because you have an unshakable belief in there only being one way, and no compromise (even imperfect ones).