Understanding what makes terrorist groups’ propaganda effective: an integrative complexity analysis of ISIL and Al Qaeda

The Islamic State of Iraq and the Levant (ISIL) became an increasingly powerful terrorist organisation in a relatively short period of time, drawing more recruits than its former affiliate, Al Qaeda. Many have attributed ISIL’s successful expansion in part to its extensive propaganda platform. But what causes terrorist groups to be effective in their communication to the public? To investigate, we examined one aspect of terrorists’ rhetoric: Integrative complexity. In particular, this historical examination provides a broad integrative complexity analysis of public statements released by key members of ISIL and Al Qaeda over a 10-year period when ISIL was rapidly growing as a terrorist entity (2004–2014). Findings revealed that (a) ISIL demonstrated less complexity overall than Al Qaeda (p <.001) and (b) ISIL became increasingly less complex over this focal time period (p <.001), while Al Qaeda’s complexity remained comparatively stable (p =.69). Taken together, these data suggest that as ISIL grew in size and strength between 2004 and 2014–surpassing Al Qaeda on multiple domains such as recruitment, monetary resources, territorial control, and arms power–it simultaneously became less complex in its communication to the public.