A critical aspect of any conflict is how well you understand your opponent. It is hardest to understand something inimical, and Islamist terrorism groups define themselves in opposition to the ‘West.’ As Jytte Klausen makes clear in her introduction, this is not a case of one state opposing another, but a conflict between state-based systems and a group of non-state actors whose central tenet is rejection of a state-based system. That makes understanding harder but even more important.

Klausen’s focus is on the Western nationals associated with terrorist plots related to Al-Qaeda. In 2006 she founded the Western Jihadism Project, which aims to facilitate archival and empirical study of the development and evolution of jihadist groups in Western democracies. Since then she – and generations of students at Boston’s Brandeis University – have created an online data archive of over 6,500 Western Jihadist extremists and their networks. Data is gathered from publicly available, open source documents including government reports and press releases, court documents, news articles, and social media postings, and is manually entered into the database by research assistants trained in both a unique coding scheme and in how to differentiate appropriate and legitimate sources from false ones.

One of the constant difficulties with the academic study of terrorism is that available data is never the complete picture: the successful terrorists stay secret; only becoming visible when they launch an attack or are prosecuted for a an offence. Additionally, data available to governments is used for law enforcement and investigative purposes, and could not, for practical reasons, be made public. Klausen’s project has sought to reduce this gap in academic understanding by collecting as much publicly available data as possible. In her methodology she acknowledges that even this has limitations – the advantage of relying on tested and verified sources such as court records is obvious, but publicly verified information will be only a fraction of the communications carried out in connection with acts of terrorism. Her research mirrors or shadows the network analysis and investigation carried out by the West’s security services, and her conclusions are similar: for many working on counter-terrorism her project will not reveal anything they did not already know. The novelty lies in the fact the data is now available for academic as well as investigative purposes. But that this research is necessary in order to raise the level of broader understanding of the scale of the challenge is clear, and it is an important contribution.

Much of the book’s narrative arc is already familiar. Klausen starts with the foundation of Al-Qaeda in a house in Peshawar in August 1988. By doing so, she brings the 1990s fully into the scope of her study, which is a welcome corrective to narratives that begin in 2001. She details the 1993 World Trade Center bombing, Al-Qaeda’s Sudan years, the Algerian GIA and the ‘Londonistan’ phenomenon, the 1998 dual embassy bombings in Kenya and Tanzania, before going on to 9/11, the day that everything changed. The book then follows the development of ‘homegrown’ terrorism: Madrid in 2004; London in 2005; and the attacks that were thwarted, including the transatlantic airliner plot of 2006. The final phase covers the rise of the Caliphate, the prevalence of the ‘Just Do It’ model for lone actors or locally organised attacks, and the vast numbers of Western citizens drawn to become foreign fighters.

What is different from other analyses is the thrust of the author’s argument: Klausen uses social network analysis to detect command and control, on the basis that we should be looking not at the ‘why’ but the ‘how.’ She contends that jihadism in the West is not simply about local grievances and disaffected youth but is the result of a strong organisational culture with a vision (Islamic awakening); a mission (the end of all states resulting in a borderless Muslim nation of righteous believers); a strategy (to be achieved through stages) and a plan. Much has been made elsewhere of insights from documentary evidence into the more mundane and bureaucratic administration of Al-Qaeda and Daesh. Klausen is more interested in using the data to address a central question: how much of this is carefully crafted and how much an accidental and haphazard movement?

Her answer draws on modern organisation and network theory; terrorist groups control their members as business leaders manage organisations. To stay in business a terrorist group must grow, replace losses, and expand while preserving core strategic objectives. Coordination of complex illegal operations across countries requires centralised command and control. A terrorist group is a political proselytising organisation, a capital raising entity and a military organisation all in one. Was Osama bin Laden a brilliant strategist? Not necessarily. But in his own destructive terms he got the concept right. His focus on shaping image and myth was a critical factor in the group’s success in the West and enabled Al-Qaeda to mimic a social movement, using friendship groups, propagandists, and locally based leaders to build a transnational terrorist organisation. Violence also helped recruit new followers (in the case of Europe 2014-17, the best propaganda came from the coverage of the attacks).

Transnationalism was a strategic choice by jihadist managers of the network who split different functions into different territories. Thus those in the West proselytised and recruited while training and combat took place in Pakistan or Afghanistan. Klausen’s network theory rests on the hypothesis that to become a terrorist you have to know one.  Her term is ‘facilitated complex social contagion’ – facilitated because networks are manipulated to promote contagion (radicalisation and recruitment). Complex, because social reinforcement is required. This is not a book about the internet, but what she describes would not have been possible without it.

The networks in the West were global by default: they evolved initially around dissidents displaced from areas of political conflict, whose radicalism pre-dated their arrival in the West, and were later kept alive by a new generation whose dual-national identities often enabled them to look at two very different geographies and cultures. In the 1990s, the western hubs of displaced North African and Middle Eastern extremist Islamists were strongly networked; the founding members of Al- Qaeda were dominated by veterans of the Egyptian Islamic Jihad and the Islamic Group, and bin Laden’s Vanguard offices in Europe and North America were built on the infrastructure of charities, offices, and centres set up by Abdullah Azzam, Osama bin Laden’s Palestinian mentor and the man credited with inventing the concept of ‘global jihad.’ The network was strengthened by veterans of conflicts in Afghanistan, Algeria, Bosnia, Kashmir, Chechnya and Iraq, and a new generation were radicalised by those conflicts.

Klausen points her spotlight on the central role of militant expatriates, and particularly proselytising individuals such as the ‘Blind Sheikh’ Omar Abdel-Rahman, an Egyptian in Brooklyn whose network was linked to the bombing of the World Trade Center in 1993; Abu Hamza al-Masri of the Finsbury Park Mosque in London; Abu Qatada al-Filistini, a radicalising religious authority and scourge of the British establishment, and later Omar Bakri Fostock, founder of Saudi Arabian jihadist network Al Muhajiroun, who was  succeeded by Anjem Chaudhury. These were the critical actors in the networks, and they were able to operate because their own activities were within the law. The ‘homegrown’ attacks in Madrid and London are shown to have had links overseas – in Spain’s case to the Libyan Islamic Fighting Group and the Moroccan Islamic Combat Group. The British men who carried out the London bombings in 2005 were part of a much larger cadre who had been trained in Pakistan. The author rightly highlights the strong role played by facilitators and middle-men, such as Rashid Rauf (later arrested in Pakistan in connection with the plot to blow up transatlantic airliners in 2006). Interestingly, she concludes that although British-Pakistanis revitalised Al-Qaeda’s European operations after 9/11, they ended up, at best, as middle managers.

The concept of ‘leaderless jihad’ pre-dated (by some margin) the war in Syria and foundation of the Islamic State. Klausen concludes that British militants were far from being leaderless; they may have been radicalised through domestic networks but it took direction and coordination to turn them into effective operatives within a decentralised cell structure. The network becomes increasingly fragmented and diffuse as the internet enabled ‘Just Do It’ terrorism, pioneered by the US citizen Anwar Al-Awlaqi, creator of Inspire magazine and of the concept of ‘open source jihad.’ This template was exploited with great success by Daesh.

As always, women are missing in network analysis, because they are hardly visible in data that rests on convictions and plots. Yet any study that really showed us how Al-Qaeda and its successors mobilised Western jihadis would need to include the role of a female support network in the West. There is only a tiny section on women; it would be terrific to understand this better.

By starting with the foundation of Al-Qaeda in 1988, the book is bin Laden-centric, which risks obscuring some of the continuities and commonality with sequential or co-existing jihadi movements. Osama bin-Laden undoubtedly precipitated a step change, but remained linked with antecedent groups active in the 1980s and 1990s. A networked analysis which scrutinises Lashkar e-Tayyiba or – even better – the militant Kashmiri group HUJI (Harakat ul-Jihad al-Islami, and its charismatic leader Ilyas Kashmiri) would illuminate starkly the local connectivity with British Kashmiri dual-nationals who simply were transnational – a quarter of a million travel every summer to Azad Kashmir, on the frontline of Kashmiri jihad. Summer holidays offered opportunities for adventure and training. Did this natural networking take place in Britain or Pakistan or both? Probably both.

That continuity is also evident in the hypnotic refrain of the ‘single narrative,’ a list of perceived injustices against Muslims which repeats: Palestine, Kashmir, Afghanistan, Iraq, Bosnia, Chechnya, Afghanistan, Iraq, Libya, Syria. The role of these conflicts in developing common cause and shared identity among western jihadists is evident. Klausen points to the jihadist revival in north Africa after 2011, and attacks on the US Consulate in Benghazi and on western tourists in Tunisia as an eerie echo of Egyptian Islamic jihadi tactics in the 1990s. This should be a stark warning about the long-term potential problem inherent in the networks developed in the Syrian War from 2011 onwards. Europe bore the immediate brunt, with a dramatic increase in the number of successful attacks made possible by ‘networks, networks, and networks.’ Klausen concludes the structural underpinnings for a jihadist comeback are still largely in place. It is difficult to see any other outcome given that tens of thousands of foreign fighters from around sixty countries are still incarcerated in North East Syria and Iraq.

This book details forensically the influence of networks on jihadis in the West. This is one perspective, but it would be interesting to flip the question around: it was the engagement of people from the West with the Al-Qaeda leadership in Pakistan and Yemen that made them such innovative and dynamic organisations. The West was not just a mobilising and recruiting ground; these networks brought in new people who shaped their strategy and kept them contemporary. After all, the proselytising influence of Anwar Awlaqi and Samir Khan, both American citizens who moved to Yemen and produced Inspire magazine, shows how devastatingly creative that engagement can be.

Western Jihadism: A Thirty Year History by Jytte Klausen, Oxford University Press, pp 560; £30