The big question here is whether the opposition would be better than Assad or not. Although, Assad is definitely an a$$hole, but if his oppositions are worse than him, we should not wish for opposition to win. That's what I call being flexible and using practical wisdom(Aristotle wisdom as they say in philosophy). Currently, Al-Nusrah, ISIS, and jabha islamiyah are the most strongest ones. FSA which was the sane part of the opposition has been weakened and now has less importance than ISIS for say.But that would mean Assad would remain in power. Only if Assad leaves I can see deal with Iran. Otherwise there will be no deal. That is what I mean there is no way back,
Template:Syrian civil war detailed map - Wikipedia, the free encyclopedia
wiki maps are pretty updated, and you can see the influence of ISIS alone, compared to rest of the opposition. let alone the FSA. The bottom line of my thought is that turkey needs to seek her own interests in this conflict. If it is satisfied by the presence of Assad, Turkey should not sacrifice her own interests here for the crazy vahabi and salafists. Do not forget that these people, arabs, have betrayed Turks multiple times and they are not our brothers and they have never treated us with good will, and have not seek turks interests at all. So, we do not have any responsibility about them. from the humanitarian point of view, Turkey hosts many of their refugees, with the situations much more better than their arab brother countries, and has done too many political actions to solve the conflict in a civil way. In which these actions are more than enough for them.