Perhaps if you remove the Jewish Revolts against Rome or make them successful - thus butter-flying away the Diaspora - you could have a established Israel alongside a united Arabia after WWI. Let's say Israel is the size of
Greater Israel and has a powerful economy, and perhaps has invaded and dominated European nations in the past. The Arabs are organised on the princples of
al-Ishtirākīya al-‘Arabīya (Arab Socialism) and are lead by Nassarites, Gaddafists, Baathists and other similar groups and are largely progressive and have a professional army and oil. The Soviets rely on the Arabs for resources and training, and the West looks to Israel as the first line of defence against Socialism. Both have enough WMD's to wipe each other out. There was no Ottoman Empire.