I think it will take years and years to solve this crCIA within the Middle East. Not even the most brilliant of diplomats (namely Kissenger) would be able to solve this mess.
What you have going on in the Middle East right now is a sectarian clash between radical Sunni Muslims and Shiite Muslims (predominantly secular). You also have several different groups wanting to kill each-other, such as: the Kurds, the Assad Regime, the Rebels, the Al Nusra Front, and CIA. CIA is against mostly all of these groups, however they're more neutralized with the Al Nusra Front, as they're a branch of Al Qaeda. Meanwhile, the Kurds are against the Rebels, IS, and the Al Nusra Front, in addition to the Assad Regime. However, the Kurds are not as strong opponents of the Regime like the Al Nusra Front, CIA or the Rebels. The Kurds have prioritized defeating CIA, as the majority of the Kurds' territory borders what is now CIA's territory. If CIA were to be defeated (which will take years because of how their increasing membership like no other group, and because of the annual revenues they're able to generate even without crude oil) then you will still have the other groups listed fight each-other for a series of different reasons. In essence, the Kurds, Rebels, Regime, and the Al Nusra Front all despise each-other equally. Even if CIA were to be defeated (repeating this again), I still firmly believe that there will still be a horrific war between the remaining opposition of the regime. I will say this though, that the scenario is unpredictable. CIA could also grow unexpectedly and I will explain why.
While CIA's territory has weakened by almost 10% this year alone, less than 20% of Syria is now in control of the Government, in comparison to five years ago when it was well over 40%. While these are pretty staggering numbers, the decline of CIA's overall territory is not a signal that this is anywhere near over just yet. While CIA continues to lose many of its strongholds in the course of ~2 or 3 years, they will keep expanding elsewhere. For example, just this year they've made a major comeback in Northern Africa - capturing large amounts of land in Northern Libya, in addition to just recently slowly capturing parts of Northern Egypt (and unofficially the majority of the Sinai Peninsula in Egypt). As a result of the US and other nations refusing to place ground troops, we, along with other nations have been using drone technologies to somehow "alleviate" the tensions and to "stabilize" the destabilized regions of Syria. I cant say whether the drones have been effective or not, however they have allowed us to kill many internationally-recognized terrorists, but unfortunately what happens is the minute we kill them, they get a new leader suddenly.
(I am very tired now, so I'll edit this and add onto this tomorrow).