Michael Kenney’s work presents a fascinating examination of al Muhajiroun, or the Emigrants, which has operated in London from the mid-1990s to the present day. This is a banned radical Islamic group that has attempted to create an Islamic state in Britain, been implicated in terrorist violence, and seen a number of its members join ISIS. Kenney presents a description of this organization’s life cycle from its beginning as a group driven by an ideological leader to its transition into a more decentralized network. Through various impressive interviews with the organization’s members, Kenney details how the group mobilized, recruited, sustained collective action, responded to counterterrorism, and handled members who exited the organization. The key contributions of this work are its network analysis of the group and the vast array of interview material. One of Kenney’s significant conclusions is that the Emigrants provided an alternative to violence for younger males prone to radicalization. This insight is new and unique and, coupled with the very interesting interviews, makes this book an impressive read.

The book begins by examining the Emigrants using network analysis. With his colleagues Stephen Coulthart and Dominick Wright, Kenney’s analysis demonstrates the evolution of the Emigrants’ network structure. The group began as a scale-free network, which is characterized by different individuals (or nodes) attaching themselves nonrandomly to a well-connected node in the network. Omar Bakri, the leader of the group, represented this key node that attracted new followers. Using impressive ethnographic data collected through years of fieldwork, Kenney demonstrates that Bakri maintained his influence over the organization by becoming a father figure, conducting high-profile rallies, and providing education to his followers.

However, even though Bakri was central to the organization, it did not collapse when he left Britain and was prevented from returning after the London bombings in 2005. Instead, the group transitioned into a “small world” network, consisting of loosely tied cells led by various veteran activists. A highlight of the book is its combination of network analysis with exceptionally rich data. The interviews further demonstrate the tactics used to sustain collective action, such as requiring attendance at study circles. Theoretically, these efforts and shifts in response to counterterrorism are predicted by current research, but we are able to see the story in both the analysis and from the words of the participants in Kenney’s work.

The remaining chapters present the participants’ motivations and strategy in their own words. We learn that those individuals joining the Emigrants were not necessarily victims of racism, but rather were disaffected youth experiencing identity issues as Muslim immigrants in British society. This largely corroborates the finding that there is no singular pathway or mechanism that causes individuals to participate in antigovernment protest or violence. Once these participants entered the organization, Kenney demonstrates how the Emigrants sought to sustain collective action by tying youth together with older veterans. Kenney describes this strategy using the concept of a “community of practice,” which is a way for participants to learn trades and skills as part of being in the activist network. Interestingly, Kenney argues that this was a double-edged sword in that the community subjected its members to dogmatic, restrictive rules, which ultimately caused many to leave as they grew older and faced the pressures of adulthood and family life.

This analysis leads to Kenney’s very interesting conclusion: although the youth of this marginalized community were at risk for radicalization, participation in this protest network allowed many of them to exercise their political anger without joining more radical groups or moving abroad to fight for the Islamic State’s caliphate. The implication is that participation in less violent protest networks may actually be a positive for society, in that it can prevent youth in marginalized communities from engaging in far more threatening activity. In addition, the pressures of the organization also caused some of these individuals to leave it, thereby keeping the protest organization at a manageable size while not being a significant threat to the state.

Although this is an impressive work and is certainly worth reading, Kenney’s focus on one group does not allow the book to provide more general lessons or answer questions about protest groups’ overall strategy. For example, we see that the Emigrants existed for a long time, continuing to protest the British government. An obvious question is why this or any activist group would continue to engage in this behavior with little to no hope of success. One possible lesson Kenney draws is that the members’ bonds and the community of practice create a reason for activist groups to exist outside of their conflict with the government. Thus activist groups may be generally ineffective at motivating political change, but may continue to exist for reasons of solidarity and community. This suggests that radical networks may serve as a social group that prevents youth from still greater radicalization. This may be a positive, but these groups also may at some point exist just to exist without a political objective. Understanding this transition, and when it occurs more generally, could be a subject of theoretical interest.

In addition, the book provides extensive data on the behavior of the protest network, but does not add an extensive amount theoretically. Although it is interesting to read about the strategies used by the Emigrants to address collective action problems, most of these can be accounted for by rational choice studies. Nor does Kenney address how shifts in the global strategic context affected the Emigrants’ behavior. For example, many of the members claimed they were following in the tradition of al Qaeda and ISIS, but no information is provided on how they responded to the split between the two organizations. Generally, the book provides so much detail about the Emigrants that it fails to discuss the larger implications for counterterrorism research.

Nonetheless, this is a very interesting demonstration of some of the core concepts in the field of social protest, terrorism, and insurgency. We see how the Emigrants altered their structure to adapt to counterterrorism, how they maintained collective action in its face, and the longer-term trends of the organization as it evolved. In addition to these dynamics, Kenney’s counterintuitive argument that the organization’s evolution enabled it to serve as a release for younger men to engage in hostile protest, but ultimately disengage from the group, is a very interesting new finding. This suggests that these groups may have social objectives outside of the political and also that states may benefit from allowing them to exist at a low level, if they can be prevented from advocating or directly engaging in violence. Whether that is possible remains to be seen. In any event, the ethnographic evidence leading to this potentially controversial conclusion makes Kenney’s work a worthwhile read.