Until the attacks of September 11, 2001, few Americans knew anything about Islam, let alone about the distinctions between Sunni and Shi‘a, the Sufi and Wahhabi, the origins of the Holy Qur’an and Shari‘a law, and the respect that all Muslims, even secular ones, harbor for the prophet Muhammad, his family, and Islamic traditions. In The Sunni-Shi‘a Divide Robert Betts traces the tortuous history of Islam’s sectarian divisions, emphasizing the most important one, the Shi‘a departure from Sunni “orthodoxy.” Although the majority of Muslims remain faithful to the Sunni sect of Islam, approximately 15 percent subscribe to the Shi‘a creed. As America’s involvement in the Middle East drags on, Betts reiterates that policymakers, scholars, and laymen alike must understand the many faces of Islam, the internal forces in the United States that have brought us into these military conflicts, and the role of Israel in the region’s escalating tensions. How the increasing hostility between the two main Islamic factions plays out on the world stage—as Sunni Turkey, Shi‘a Iran, and their allies vie for dominance—is of major consequence for everyone, especially financially strapped Europe and the United States.