A friend asked me this today, and I realized that with my knowledge of the middle east, I didn't have an answer for him. So my question for you guys is has there ever been a lengthy period of peace in the region. Between things like the Crusades, the Palestinian conflict, etc it's obviously had more than it's share of conflict.
Most places have not had extended peace, war has been pretty common in all areas of the world. When places get an extended peace they are usually noted. Pax Romana for instance was 120 years of peace from ~70 to ~190 AD, at this time Rome owned much of what is referred to at the Middle East, including North Africa, Egypt, Palestine, Syria.
There were always periods of relative peace during times that the middle east was ruled by a single political entity. This includes the Achaemenid (Persian) Empire, Roman Empire, Umayyad Caliphate, and Ottoman Empire.
Keep in mind however that the periods of time during which these empires were either rising or on the decline were generally quite violent as well.