Wehrey dispassionately chronicles sectarianism in the three Gulf countries where Shiite-Sunni tensions are arguably most significant: Bahrain, Kuwait, and Saudi Arabia. He details how regional developments, above all the Islamic Revolution in Iran in 1979, the U.S. invasion of Iraq in 2003, and Hezbollah’s confrontation with Israel in 2006, all fanned the embers of sectarian animosity. Nonetheless, in Wehrey’s view, the root causes of the conflict lie in weak political institutions, the systematic disenfranchisement of minority groups, and the irresistible temptation of local political actors to exploit sectarian sentiments to advance their agendas. The royal families that rule all three countries seek at all costs to prevent any alliance, in the name of a reform agenda, between moderate Shiites and moderate Sunnis, although one could easily argue that such an alliance would serve the long-term interests of all three monarchies. Wehrey might leave the reader wondering when artificial disputes instigated for short-term political gain become bloody enough to be considered real and possibly become intractable.