answer:The real problem is that every one of the players (Syria, ISIS, Iran, US, Russia, Saudi Arabia, and the rebels) has entirely different reasons for screwing around in Syria. And off on the side, there is Israel. Russia is in cahoots with Assad to save Assad’s butt; only secondary is their dislike of ISIS. The rebels can’t stand Assad but they don’t like ISIS either. Saudi Arabia hates Iran, hates ISIS because they see it as a threat, sort of supports the rebels because they don’t like ISIS. And then there’s the US who is sort of an ally to Saudi Arabia and Russia at the same time (ISIS enmity) but dislikes Russia because of the whole Crimea thing and the fact that Putin is becoming another czar. Bottom line: it is a real mess. They all have stated goals and unstated goals, and there is no way for them to reach any sort of a meeting of the minds. The US probably should have gotten involved three years ago – but there’s no guarantee that doing so would have changed anything. My guess is that Syria is going to come out ugly no matter what, and won’t get settled for a LONG time.