I have posted this before, but modernity has completely altered the economic logic of a State or a tribe. Most importantly, land itself is literally approaching irrelevancy. It still must be farmed and optimized but all the customers are living on sheets of concrete and physical proximity is optional.
From this it follows that we need to establish both the super state to which no one actually belongs but all somewhat participate as needed and the natural city state which captures the cultural aspirations of a tribal grouping or any such grouping as people accept.
Thus we can establish city states for the Palestinians in say Tyre, Bethlehem, and Gaza. Everyone there today become a direct citizen of his city state. The rest of the land is then managed by say Israel. Israel has its own City States if necessary to establish individual citizenship. Think of all those orthodox types. What this means though is that everyone has the right to buy and sell land and open enterprises in the balance of all the lands.
After all, good land husbandry happens to be a universal objective and requires conforming laws and willing hands. Thus a Palestinian, a citizen of say Tyre, could own a farm near Jerusalem and actually reside there most of the time. With common interests with one's neighbors, security issues end.
This has to be applied throughout the Middle East and in many other places as well. What it voids is a conflict based on the spoils system of governance which will take a long time to end.
In Syria it is obvious that the alowites of Bashir Assad need their own established City States as do the Sunnis and the Kurds at least. The rest is mostly desert now but that can change as well once wilful cooperation becomes possible...