Nationalism has been inhibiting peace in the Middle East for at least a century. For example, nationalism helped to inhibit peace in the last days of the Ottoman Empire. Then, Arabs in areas like Palestine wanted to be free from Turkish rule. The Arabs were helped during WWI by the Allied powers. This Arab nationalism inhibited peace. Today, perhaps the best example of nationalism inhibiting peace is the Arab-Israeli conflict. In this conflict, nationalists on both sides want very badly to control the area. They have been in conflict because of this since the creation of the State of Israel in 1948.
make sure to include background info to the arab-israeli conflict and details such as dates , people, and places well :)