Griswold takes the reader on a journey along the tenth parallel--the line of latitude seven hundred miles north of the equator--where we find a geographical and ideological front line where Christianity and Islam collide. Religious conflicts are also conflicts about land, water, oil, and other natural resources, and that local and tribal issues are often shaped by religious ideas. A deeply personal account, Griswold also places the intersection in its historical and social context. A must read.