More Combatants, More Terror?: An Empirical Test of the Outbidding Thesis

In armed internal conflict, violence against civilians is frequent. For insurgent groups, so-called terrorist acts are an important part of conflict with the state and yet there are numerous unanswered questions about the role and uses of terrorism during these conflicts. This paper examines the causes of terrorism in the context of a larger struggle between a state and insurgent groups. In particular, we examine the hypothesis that outbidding among insurgent groups results in more suicide terrorism specifically and also more terrorism of any type. A global analysis of terrorism from 1970–2004 provides limited support for Bloom’s thesis related to suicide terrorism. An extension of the argument to all types of terrorist attacks provides even less support for an outbidding thesis. Similar to Pape’s argument, the outbidding thesis has received considerable attention in academic and policy circles. But both hypotheses have received little empirical support and suggest that considerable cross-national work is still needed to understand suicide terror adequately.