ABSTRACT
The goal of this chapter is to assess whether the way a terrorist cell operates (e.g., plans, prepares, and executes its attacks, hides from the authorities, gains expertise, etc.) is in some way related to the composition of the cell in terms of the types of perpetrators. To this end, this chapter will present a case study of the 9/11 hijackers. First, the available perpetrator typologies will be reviewed in order the select a typology that can be applied to the 9/11 hijackers. Then, using that same typology, all nineteen hijackers will be categorized in order to establish the composition of the cell. The next step is the formulation of hypotheses. Given the composition of the cell, how would one expect the terrorist cell to behave? The third step is the testing of the hypotheses: did the 9/11 hijackers act the way one would expect on the basis of the hypotheses? The conclusion will assess the findings and explain why and how they are important for the field of Perpetrator Studies. The question whether perpetrator typologies have the potential to move the field of terrorism studies forward will be addressed in the conclusion as well.
