1
Although publicity is often characterized as the lifeblood of terrorism (e.g., Crenshaw, 1983;
Hoffman, 1998; Schmid and Graaf, 1982), the willingness of groups to claim responsibility for
acts of terror varies considerably. A 1985 RAND report found that more than sixty percent of
terrorist acts in the 1960s and nearly forty percent of terrorist acts in the 1970s went unclaimed
(Cordes et al., 1985). Anonymous attacks, like the September 11
th
attacks on the World Trade
Center and the Pentagon, continued into the 1990s and early twenty-first century alongside
violence perpetrated by groups like the Al Aqsa Martyrs Brigade, appear eager to take credit for
their work. What accounts for the difference?
I argue that that the rate at which groups take credit for acts of terror is influenced by the
competitive context they face. Competition has long been seen as a significant influence on the
behavior of terrorist organizations, yet few efforts have been made to specify and test the
relationship between competition and terrorism. Drawing on research on the economics of
advertising (e.g., Telser, 1964), I argue that groups publicize their involvement in terror attacks
to communicate demands and signal commitment to particular causes. As the number of groups
active in a particular arena increases, i.e., as the context becomes more competitive, the ability of
any group to rely on violence alone to identify themselves to opponents and supporters declines.
Therefore, as the number of terrorist organizations increase, groups take credit for attacks more
frequently in order to communicate more clearly with their intended audiences. I examine the
plausibility of this argument about competitiveness using cases of terrorism committed in Israel,
Northern Ireland, and England between 1968 and 1977. The results suggest that situational
competitiveness is a stronger predictor of credit taking than the principle rival explanation that
credit taking is driven by the ideological proclivities of groups.
Convention