Why do some insurgent groups target American nationals? At first glance, it appears to be a risky strategy, inviting retaliation from the world's foremost military power. But a number of incentives make anti-American violence an attractive option for certain insurgent organizations.Killing Americans explores the risk factors involved in insurgent groups' decisions to plan and conduct attacks on Americans. If, for example, American culture is prevalent in a given country, this tends to lessen the likelihood of attacks. On the other hand, extremist ideology and the deployment of American military forces in the area encourages them. And the consequences for an insurgent group that carries out violence against American citizens can be beneficial: they can raise their profile among sympathizers and gain credibility with would-be recruits. Drawing on quantitative analysis and case studies from around the world, this book shows that insurgents tend to become more lethal and more likely to survive after having made their first attacks on Americans. By considering American involvement abroad, organizational traits of insurgent groups, and potential consequences of attacks, Killing Americans provides a comprehensive account of variation in insurgent anti-American violence.