Terrorist Group Survival as a Measure of Effectiveness

Some terrorist groups only carry out one attack and then disappear, while others wage campaigns of terror for decades. Why do some terrorist groups last much longer than others? A growing body of research provides in-depth empirical evaluation of this important question (Cronin 2006, 2009; Daxecker and Hess 2013; Gaibulloev and Sandler 2014). However, there has been little effort to consolidate the findings that exist thus far. The topic of terrorist group endurance is pertinent to the theme of this edited volume, the effectiveness of terrorism, because endurance can be seen as a component of effectiveness. Terrorist groups need to survive before they can hope to achieve political success. “The minimum goal of any organization is survival,” argues Crenshaw (1987), drawing on classics of organizational theory (Wilson 1974). In spite of the importance of understanding terrorist group longevity, there is still confusion regarding why some groups last longer than others. A dozen or so quantitative analyses of global samples of terrorist groups have sought to understand group endurance, as this manuscript explains, but results are mixed. Few variables are consistently associated with group endurance. One set of factors that shows some association with group longevity involves interorganizational dynamics – in particular, terrorist group cooperation and competition. Some studies find cooperation helps group survive, and other studies find a link between competition and group endurance. Cooperation and competition are interesting because research has shown that terrorist group alliances are associated with group lethality (Asal and Rethemeyer 2008; Horowitz and Potter 2014), and terrorist group competition has been argued to contribute to innovations and more extreme violence (Bloom 2004, 2005; Conrad and Greene 2015). Both types of intergroup relationships are fairly common among terrorist organizations.