Recent decades have seen an increase in the number of studies on violent Islamic extremism. Scholarship on this topic has discussed the theological content of jihadi Salafism and its intention, the challenges of internal coherence and leadership within jihadi organizations, the drivers of jihadi recruitment, and the role of the state as a (de)radicalizer of violent extremism. Thomas Hegghammer, Aaron Zelin, and Jacob Zenn examine the phenomenon of violent Islamic extremism in different world regions and at different moments in time.

In The Caravan: Abdallah Azzam and the Rise of Global Jihad, Hegghammer reexamines the life of Abdallah Azzam, the Palestinian cleric who led the mobilization of Arab fighters to Afghanistan in the 1980s and who is considered to be the founding father of transnational jihadism. The book thus discusses the historical role played by a particular individual in the spread of transnational jihadi ideology. By contrast, Zelin’s Your Sons Are at Your Service: Tunisia’s Missionaries of Jihad and Zenn’s Unmasking Boko Haram: Exploring Global Jihad in Nigeria analyze the formation, subsequent rise, and further evolution of jihadi terrorist organizations. All three emphasize the role of Salafi jihadi ideology and extensively refer to the particular political and socioeconomic context in which Islamic extremism manifests itself. The books are clearly written and cover extensive historical and analytical ground. All three add substantial knowledge to the existing canon on jihadism.

The research question that Hegghammer tries to answer is “why jihad went global” (p. 1). The conflict in Afghanistan, which began with the Soviet invasion in 1979, was the first to attract foreign fighters, and it came to be “the most transnational rebel history in modern history” (p. 2). Azzam was able to reorient Islamic extremists from their respective domestic locales to Afghanistan. The emergence of the so-called Afghan Arabs therefore was a formative event, which so far has not been analyzed in the Anglophone literature. This study, which the author began to research in 2007, draws on previously published books about Azzam’s life in Arabic, jihadi publications, recorded lectures, and interviews with people who engaged with Azzam. It provides an in-depth chronological account of the various stages in Azzam’s life: his birth in Palestine, his first contacts with the Muslim Brotherhood, his career as a university academic, his conservative teachings and writings, the conditions in Afghanistan at the end of 1981, the background to Azzam’s fatwa calling for Muslims worldwide to come to Afghanistan and fight global jihad, the dire modalities of the recruitment of foreign fighters, the fragmentation of the jihadi movement in Afghanistan, and the assassination of Azzam on November 24, 1989, under mysterious circumstances. The book comes with an online companion (www.azzambook.net) that allows scholars to access an array of primary sources and can also be used as a teaching tool.

Reading through the main corpus of the book—508 pages, excluding the extensive bibliography—never gets tiring. This is the result of two factors, the first of which is the exceptional clarity of Hegghammer’s writing. Despite the complex and multifaceted nature of the topic at hand, the book is a pleasure to read. The second factor, which is related to the first one, is the author’s ability to link Azzam’s thinking to the unfolding political situation in the Middle East from the end of World War II onward. This makes the book as much a review of Middle Eastern contemporary history as it is a book about Azzam. The book helps readers understand not just what drives individuals to become mujahideen but also provides fascinating insights into the day-to-day challenges of keeping transnational jihadism going. Hegghammer provides a holistic analysis of the drivers of jihadi radicalization. He highlights three key elements that enabled Azzam to recruit the mujahedeen: motivation—the creation of an Islamic foreign-fighter doctrine; organizers—individuals disseminating the foreign-fighter doctrine across the globe; and low constraints—the lack of any activity in the Arab world and the West to prevent recruits from going and organizers from operating. It deserves notice that the United States was the only nation in which Azzam was able to establish a national affiliate organization.

The conclusion elaborates on all three drivers and discusses Azzam’s contribution to the Arab involvement in Afghanistan. Here, the author briefly discusses the commonalities between the conflict in Afghanistan and the more recent conflict in Syria. It would have been useful to have a more extensive discussion of the lessons Western governments might take from what happened in Afghanistan three and a half decades ago. This is not a critique of the book, because Hegghammer early on states that his goal is to provide a historical analysis of the events and factors that shaped Azzam’s life. His book will be an instant classic among scholars researching transnational jihadism. Yet, his rigorous analysis does raise the question of whether the three factors, which enabled the mujahedeen in the early 1980s, continue to operate unabated.

Aaron Zelin’s Your Sons at Your Service: Tunisia’s Missionaries of Jihad explores the history of Tunisian jihad. It retraces the emergence of Ansar al-Sharia (AST), a jihadi group that formed in Tunisia in the direct aftermath of the Arab Spring. Zelin discusses the conditions enabling the group, why it prioritized conversions and education over violent activities (a strategy known as “dawa first”), and why the AST ultimately failed to fulfill its mission in Tunisia. Zelin draws on jihadi bibliographies, the Western Jihadism Project database, materials released by AST, court files, Libyan and Tunisian government documents, and information derived from meetings with AST members during four research stays in Tunisia.

The book starts out by providing a historical analysis of the rise of the Islamist movement following Tunisian independence from France. Although the Tunisian state implemented a strictly secular political system and there were few jihadi ideologues in Tunisia before 2011, Tunisian jihadism did not emerge out of nowhere. Long before the Arab Spring, Tunisian jihadi fighters were present but operated largely outside of Tunisia. They first emerged in Afghanistan during the early 1980s and subsequently participated in the jihad in Bosnia and Algeria.

Zelin explains the rise of domestic jihadism in Tunisia by pointing to the post-2011 Tunisian government. After the overthrow of the long-lasting dictator Ben Ali in February 2011, the transitional government declared a general amnesty, freeing a significant number of convicted jihadis from prison. This decision enabled the AST to become a major national security threat between February 2011 and August 2013. In August 2013 the government declared the AST a terrorist organization, thereby curtailing its ability to operate within Tunisia’s borders. To put it more provocatively, the Tunisian state became a facilitator of violent Islamic extremism, even though it had the capacity to demobilize extremism later on. The AST did not collaborate with or become co-opted by the al-Naddah party, Tunisia’s political Islamist movement, which was part of the post-2011 government. However, the al-Naddah administration showed a consistent bias in favor of the AST. Members of the AST, who resorted to violence against the state, generally received shorter prison sentences and punishments than secular perpetrators of the same crimes. This bias further demonstrates that the presence of political Islamism does not necessarily undermine jihadi activity as some have suggested. The chapters discussing the AST’s religious, educational, and social activities convincingly argue that jihadi organizations are susceptible to outside advice and strategic learning. Jihadis might be ideologues, but to achieve their goals, they acknowledge local realities and borrow from Western strategic thinking.

Zelin’s step-by-step analysis of the response of the Tunisian state toward AST-orchestrated violence is particularly illuminating. Zelin fills a lacuna in the jihadism literature, in which there is a paucity of studies on Tunisian jihadism. Scholars interested in other countries will find his study an important empirical point of departure for their own works. The fact that the AST increasingly focused on the jihad in Syria and Iraq raises at least one provocative question: If the Tunisian state was able both to facilitate and undermine jihadi activity, what precisely should states do when confronted with domestic jihadi terrorism? Unfortunately, Zelin does not address this question and explicitly refrains from theorizing his findings.

Whereas Zelin provides the first systematic analysis of Tunisian jihadism, Jacob Zenn contributes to the growing field of studies about Boko Haram, one of the world’s most lethal and brutal Salafi jihadi groups. By highlighting Boko Haram’s international and regional jihadi influences, Zenn delivers a pathbreaking study of jihadism in Africa in general and in Nigeria in particular. The book draws on new Arabic and Hausa sources; correspondence between Boko Haram, Al Qaida, and ISIS; Nigerian government sources; and interviews with members of various Boko Haram factions. This book also comes with an online companion through which readers can access many of the book’s sources (https://unmaskingbokoharam.com).

Zenn shows that jihadism in Nigeria has its origins in the early 1990s when the first Nigerian Salafis came into contact with members of Al Qaida in Sudan, where Osama bin Laden then resided. Nigerian jihadism thus is at least one decade older than scholars conventionally assume it to be. Through a very intricate and dense analysis, Zenn illustrates the personal and organizational links between Al Qaida of the Islamic Maghreb (AQIM), al-Shabaab, and the so-called Nigerian Taliban, whose members self-identified with global jihadism and whose core later became Boko Haram. Most studies about Boko Haram elaborate on the Nigerian state’s crackdown on it in July 2009, which resulted in the killing of its then-leader in a police station under dubious circumstances. Zenn demonstrates how the close cooperation between AQIM and Boko Haram enabled the latter’s comeback. Boko Haram’s successful car bombing attacks between 2011 and 2013, for example, would not have been possible without training and advice by AQIM. During this period, Boko Haram also significantly widened the radius of its activities. Boko Haram’s interconnectedness with AQIM, Al Qaida, and, later on, ISIS had direct implications for the leadership struggle within the organization. At different moments in time, AQIM and ISIS took sides in favor of specific individuals and against Abubakar Shekau, who emerged as Boko Haram’s leader after the 2009 crackdown.

Zenn’s analysis goes further. He demonstrates that at the heart of these divisions were questions of theology, in particular questions about how to go about fighting jihad. Shekau’s exceptionally hardline approach viewed Muslim lives as collateral in the fight against the Nigerian state. Under his leadership Boko Haram attacks resulted in the brutal killings of hundreds of innocent civilians, which sparked controversy inside the group. Thus, as with Hegghammer’s and Zelin’s works, readers gain a firsthand account of the internal dynamics within jihadi Salafi organizations.

The book goes far beyond any previous analysis of Boko Haram. It makes a compelling case that the group must not be confined to the Nigerian context, although Zenn does not deny the importance of local factors. The book demonstrates, however, that Boko Haram’s trajectory should be seen as the result of global and regional dynamics; thus, socioeconomic factors such as joblessness are not the driving force behind its emergence. The book is a remarkable scholarly achievement that adds new and provocative layers to the study of jihadism in Africa.