We shall never give in to terrorists’ demands, as doing so would merely encourage other terrorists who come to learn that violence pays. After all, terrorists are rational enough to copy rewarding behavior. This basic assumption is intuitive and simple. Perhaps unsurprisingly, the imperative to never concede dominates counter-terrorism policies. Is, however, terrorist contagion an automatic consequence of concessions? What if the compelling logic of the rational copycat reaction to concessions is too simple? In fact, we have no evidence to support the logic1 of the no-concessions doctrine.2 It must not necessarily be the case that terrorists regard all concessions worthy of exhibiting copycat behavior, and it must not always be the case that copycat behavior ushers in an increase in violence. Assumptions about rational copycat reaction to concessions fail to problematize whether concessions are perceived as a reward and what it is that is being perceived as rewarded behavior. Rational choice explanations remain void if they fall short of breaking up the black box of cost-benefit analysis and ignore the element of perception. Clearly, whether I copy someone is conditioned by my evaluation of the concession as being an actual reward or in fact, rather, a punishment. If the latter is the case, this would lead me instead to react quite differently to prevent this punishment and innovate instead of copy behavior. Even if I come to conclude that the concession is rewarding, what I perceive to be the rewarded behavior worthy of being copied is not automatically guaranteed. Copying someone implies minimizing the difference between oneself and the role model. However, what one perceives as the determining difference is crucial for what is regarded as the source of the role model’s success. Whether my colleague got promoted because he is simply better than me, or because he stopped working poorly, might not make a major difference for the promotion, but can make an immense difference for my decision on how to follow suit. What we perceive as being rewarded determines to a great part what we copy. Our perception of what is being rewarded, in turn, is influenced by our relation to the role model. Whether I follow similar or competing goals as my colleague influences my judgment about the cause of his promotion. The same holds true for terrorist reaction patterns. Of course, terrorist groups might perceive terror just like renouncing terror – as the rewarded and hence

no-concessions imperative argue that conceding only serves to signal that violence pays, the challenge for employing concessions constructively is “to make it quite plain that dropping violence will be rewarded.”3 But how do we reveal what precisely terrorists perceive as rewarding or not? Clearly, a major research hurdle to confront is the sheer impossibility of disclosing how precisely terrorist groups judge concessions. Talking to terrorists can contribute to fill this gap. Practically, governments often do negotiate with and concede to terrorists. The inconsistency of no-concessions policies is a convenient point of departure for researching terrorist perceptions. It is through dialogue and the reintegration of former terrorists into law-abiding society that the terrorist subject becomes most accessible for interviews.4 Accordingly, the author completed field research in Egypt, Syria,5 Colombia and Turkey, and spoke with – among others – former and current members of listed terrorist groups. The goal of this empirical research was to find out whether conceding to terrorists indeed serves to radicalize other terrorists. In short: whether the noconcessions doctrine can be confirmed. The field material and subsequent analysis call the no-concessions doctrine into question: concessions do not always lead to copycat phenomena, and, if they do, it is not always terrorism that is copied. Concessions to terrorist groups have varying effects on other groups depending, for example, on the types of concessions – selective or collective6 – or on the types of the terrorists’ motivations in relation to those groups receiving concessions – similar versus competing motivations.7 While the type of concession determines whether concessions are perceived by terrorists as failure or success, and whether these react with innovation or copycat in the consequence, the relation of similarity or competition determines whether violence or renouncing violence serves as the role model behavior for copycat or innovation mechanisms. The implications for policy are apparent: it is not necessarily the case that a firm no-concessions stance should be politically signaled by all means. In fact, concessions can – under certain conditions – be employed to reward the renunciation of violence. This book aims to introduce and explain the variation in terrorist reaction and applies the findings to the policy discourse.