In 2011, the United States government declared a cyber attack as equal to an act of war, punishable with conventional military means. Cyber operations, cyber crime, and other forms of cyber activities directed by one state against another are now considered part of the normal relations rangeof combat and conflict, and the rising fear of cyber conflict has brought about a reorientation of military affairs. What is the reality of this threat? Is it actual or inflated, fear or fact-based?Taking a bold stand against the mainstream wisdom, Valeriano and Maness argue that there is very little evidence that cyber war is, or is likely to become, a serious threat. Their claim is empirically grounded, involving a careful analysis of cyber incidents and disputes experienced by internationalstates since 2001, and an examination of the processes leading to cyber conflict.As the authors convincingly show, cyber incidents are a little-used tactic, with low-level intensity and few to no long-term effects. As well, cyber incidents are motivated by the same dynamics that prompt regional conflicts. Based on this evidence, Valeriano and Maness lay out a set of policyrecommendations for proper defense against cyber threats that is built on restraint and regionalism.