Simultaneous Attacks by Terrorist Organisations

While terror attacks that are a part of a coordinated effort receive attention in the popular media, they have not received much attention in the academic literature. The decision to carry out simultaneous attacks should be examined as one of the choices a terrorist organisation makes about the method of attack. Determining the impact of simultaneous attacks vis-à-vis a single attack can explain why groups would use this method. Up to one quarter of all attacks coded in two major databases, GTD and ITERATE, may be part of a simultaneous campaign. Empirical analysis shows simultaneous attacks are more likely to be successful and cause more fatalities, though not in a one-to-one fashion. These results underline the importance of considering simultaneous attacks in empirical analysis.