How did Iran's clergy justify their country's devastating eight-year war with Iraq? Seeking to rationalize Iran's war in Islamic theological terms, this study examines Iran's conduct up until the cease-fire and acceptance of Resolution 598 in 1988. The author offers an explanation of each policy and action of Iran's clerical leaders with reference to the Qur'an, theological writings and tradition, and Islamic historical precedent. The concepts of nationalism and the Islamic nation-state, pan-Islamism and international relations are all discussed in the context of Iran's policy of total war.