Fragmented societies in middle East, an irreversible fact?

Before the twentieth century, Palestine, as many other Arab countries, was under the Ottoman Empire. During that period, the Palestinians and the Arabs were one state, one nation and they all cared about their Arab nationalism. They were all Arabs who wanted to get rid of the Ottoman Empire. However, the First World War took place and the Ottomans lost in this war. The result of this war was many agreements signed between the winning European countries such as San Remo, Sykes Pico and Belfour Declaration which all resulted to the division of the Arab nations.