I often feel like the Middle East is a victim of poorly drawn post-colonial borders. One nation will back another nation at one point and then at another point back another nation. The cultural diversity that exists within these countries is often forgotten. A country like Iraq not only has a Sunni vs Shia thing going on but also a Persian vs Arab conflict to contend with. And then throw the Kurds in there on top of it all. Lebanon has Alawis, Christians, Sunnis, Shia, Arabs, Syrians, etc.
Given all the diversity, it can be difficult for foreigners to keep up with all that is happening and who is who in the zoo. We rely on 30 second sound bites from CNN/BBC to get our propaganda on who the good guys and the bad guys are today.
The post-colonial borders just seem to indiscriminately cut across so many cultural groups that it is no wonder that the allegiances in the Middle East are constantly in flux. And then you throw in Western proxy manipulation on top of that and its a giant mess.