Iraq and Iran are the two most important states in the Gulf region, given their population size, military strength, and the potential threat they pose to other states in the region. This book enhances our understanding of the troubled relationship between Iran and Iraq, placing it in historical context, examining the rapid deterioration leading to the eight-year war that started in 1980 and the effects of that trauma, and exploring the ongoing issues that currently bedevil bilateral relations. The authors cover such central issues as how each side has sought to use opposition groups in the other state to weaken it, ethnic divisions, the role of outside states (especially the United States), and a fascinating account of how the war affected a generation of Iraqis and Iranians. The role of the U.S. in the region and how U.S. policy has affected the two states are also considered. This book provides a basis for understanding the background of a tumultuous relationship that is entering a new era.