When Heads Roll: Assessing the Effectiveness of Leadership Decapitation

Abstract Leadership targeting has become a key feature of current counterterrorism policies. Both academics and policy makers have argued that the removal of leaders is an effective strategy in combating terrorism. However, leadership decapitation is not always successful, and existing empirical work is insufficient to account for this variability. As a result, this project answers three primary questions: (1) Under what conditions does leadership decapitation result in the dissolution of a terrorist organization?; (2) Does leadership decapitation increase the likelihood of organizational collapse beyond the baseline rate of collapse for groups over time?; and (3) In cases where decapitation does not result in group collapse, to what extent does it result in organizational degradation and hinder a group's ability to carry about terrorist attacks? I develop a dataset of 298 incidents of leadership targeting from 1945–2004 in order to determine whether and when decapitation is effective. First, I identify the conditions under which decapitation has been successful in bringing about organizational decline. The data show that a group's age, size, and type are critical in identifying when decapitation will cause the cessation of terrorist activity. As an organization grows in size and age, it is much more likely to withstand the removal of its leadership. Organizational type is also significant in understanding the susceptibility of an organization to decapitation. Ideological organizations are most likely to experience a cessation of activity following the removal of leader, while religious organizations are highly resistant to leadership decapitation. Second, I determine whether decapitation is an effective counterterrorism strategy that results in organizational collapse. The data show that decapitation does not increase the likelihood of organizational collapse beyond a baseline rate of collapse for groups over time. Organizations that have not had their leaders removed are more likely to fall apart than those that have undergone a loss of leadership. The marginal utility of decapitation is negative for many groups, particularly for larger, older, religious, and separatist organizations. Finally, I look at the extent to which decapitation results in organizational degradation and hinders a group's ability to carry about terrorist attacks. Case studies illustrate whether decapitation has an effect on the operational capacity of an organization by identifying whether the removal of key leaders changes the number and lethality of attacks. If certain organizations are more resilient than others, it is important to know when decapitation should be effective and when it could lead to counterproductive outcomes. Overall, these findings illustrate the need to develop a new model for evaluating the efficacy of leadership decapitation and for developing effective counterterrorism policies. Jenna Jordan is a PhD Candidate at the University of Chicago. For helpful comments on previous drafts, I would like to thank Mia Bloom, John Campbell, Alexander Downes, Anne Holthoefer, Chaim Kauffman, Charles Lispon, Jennifer London, John Mearsheimer, Michelle Murray, Robert Pape, Sebastian Rosato, Keven Ruby, John Schuessler, Paul Staniland, seminar participants at the Program on International Security Policy at the University of Chicago, the TISS New Faces program, the Lehigh University Speaker Series, the Chicago Project on Suicide Terrorism, and two anonymous reviewers for Security Studies.