Book excerpt: Examines the dynamics that drive changes in the religio-political landscape of the Muslim world, the effects of 9/11, the global war on terrorism, and the war in Iraq. The authors present a typology of ideological tendencies; identify the factors that produce religious extremism religious violence; assess key cleavages along sectarian, ethnic, regional, and national lines; and identify possible strategies and military options for the United States to pursue in this critical and volatile part of the world.