In recent years, the geopolitical rivalry between Saudi Arabia and Iran has dominated the headlines. Many have charted the polarization between a Saudi-led Sunni camp and an Iranian-led Shia one, assuming that a predominantly Shia state like Iraq would automatically ally with Iran. In this compelling account, Katherine Harvey tells a different story: Iraq's alignment with Iran was not a foregone conclusion. Rather, Saudi efforts to undermine Iran have paradoxically empowered it. Harvey investigates why the Saudis refused to engage with Iraq's post-2003 Shia-led government, despite continual outreach by Iraq's new leaders and considerable pressure from the United States. She finds that certain deeply ingrained assumptions predisposed Saudi leaders to see a Shia-led Iraq as naturally beholden to Iran: the view that Iran is inherently expansionist, and the belief that Arab Shia tend to be loyal to it. This outlook was simplistic, even downright inaccurate; and, in refusing to engage, the Saudis created a self-fulfilling prophecy. As Harvey demonstrates, members of Iraq's new government initially sought to establish a positive relationship with Saudi Arabia, and to pursue a course independent from Iran. But, isolated and rejected by Saudi King Abdullah, Iraq ultimately had nowhere else to turn.