Profiled on the front page of the Wall Street Journal, Iranian-born scholar Vali Nasr has become one of America's leading commentators on current events in the Middle East, admired and welcomed by both media and government for his "concise and coherent" analysis (Wall Street Journal). In this "smart, clear and timely" book (Washington Post), Nasr brilliantly dissects the political and theological antagonisms within Islam. He provides a unique and objective understanding of the 1,400-year bitter struggle between Shias and Sunnis, and sheds crucial light on its modern-day consequences?from the nuclear posturing of Iran's President Ahmadinejad to the recent U.S.-enabled shift toward Shia power in Iraq and Hezbollah's continued dominance in Lebanon.