Online Terrorism Studies: Analysis of the Literature

This article summarizes the recent research note that examines the literature on online terrorism studies, published by Ali Unlu and Kamil Yilmaz.

By Kamil Yilmaz

There has been a steady increase in the number of scientific productions on terrorism during the last two decades. One specific area of research that gained traction is online radicalization and terrorism, which has rapidly developed in recent years due to developments in and affordances provided by the Internet and social media. While there are studies examining research on terrorism, there is a dearth of research that focus on examining particularly studies on online terrorism. To fill this gap, we wanted to understand how online terrorism concepts have been studied over the years and how funding influences the research topics and current trends in the field.

To achieve these tasks, we employed bibliometric and statistical analysis of published articles, and analyzed article citation, bibliographic co-citation and coupling networks, keyword networks as well as country collaboration networks by utilizing ISI Web of Knowledge Social Sciences Citation Index (SSCI) database and R, VosViewer and Gephi analytics software. In a nutshell, we examined 8,466 articles in 2,090 journals published between 2001 and 2022.

Core Terrorism Journals vs Other Journals: The importance of funding

Our initial analysis of the data necessitated us to differentiate between core terrorism journals and other journals. Appending several journals to the list created in prior work, we focused on 14 terrorism journals that accounted for the 256 articles in our dataset. The remaining 8,210 articles were published in other journals, predominantly in Computer Science journals.

One of our major findings was that core terrorism journals focus on threat of certain groups and counter strategies of those groups while paying less attention to right-wing groups or hate speech emerging from own citizens. In other words, it seems that terrorism is studied as an external threat and internet as a playground of terrorist groups mainly for propaganda and recruitment. On the other hand, most of the studies in non-terrorism journals focus on hate speech, populism, gender media and social media studies. The new research tools, such as text mining, machine learning and deep learning, enable researchers to study different aspects of the phenomenon but these works are not published in terrorism journals.

We also found that Computer Science publications received more funds than the publications in terrorism journals. Among 10 most productive journals that published articles on online terrorism, there are no journals that received funding other than Computer Science journals. While more than half of publications in Computer Science field received funding, the ratios for Criminology, Sociology and Political Science are quite low, where terrorism studies are more likely to be studied. It is curious to know why this is the case; we can speculate that funders may be supporting new research methods on social media platforms that focus on hate speech and populism research, which may be considered an internal threat for social wellbeing.

Intellectual Topography of the Subject

Our findings indicate that among 2,090 journals, only 43 (around 2%) journals constitute the most effective journals in terms of their citation performance. The top ten list of journals represent the two main division of the journals, between computer science and terrorism journals. Computer science journals produce more than the terrorism and any other field journals. When we focused only on terrorism journals, Studies in Conflict and Terrorism journal published 38.7% of all articles, followed by Terrorism and Political Violence (31.6%) and International Journal of Cyber Warfare and Terrorism (10.9%).

In analyzing the boundaries and interactions between disciplines, bibliographic coupling (BC) of the articles revealed that research on online terrorism has five major groups of research fields, which include Computer Science Journals (the biggest network), health and psychology journals, and mainly terrorism and communication journals.  Our BC analysis, taking the journals as the reference point, found no single major centre; each field stays on the edges, while some journals being in the middle of these clusters.

On the other hand, our co-citation (CC) analysis showed that the field has emerged from five different clusters. Social-science oriented journals, which constitute a closely-knit network with psychology and other health journals, are far from other clusters e.g., computer science and business journals. In addition, our BC analysis show that Computer Science and Communication Science are very closed to each other with a higher density. Terrorism, political science, and communication journals form their unique clusters, but their research mainly continues within their own cluster.

Key Growth and Recent Trends

When we analyzed the keyword growth in the last two decades, we observed that before 2010 only three concepts were studied, mainly around radicalization on the Internet, but the diversity of the concepts is increased after 2010. Besides certain terrorist groups, social media, extremism, violent extremism and propaganda were popular concepts; extremism, social media and terrorism studies gain more attention later.

Our network visualization of keywords showed that hate speech, Twitter and populism are the major topics heavily studied recently. New research techniques, such as machine learning, natural language processing and deep learning are the essential tools to study these concepts on social media.  In addition, political communication, alt-right groups, ISIS, and radical right are also recent concepts that authors pay attention nowadays.

Whither Online Terrorism Studies?

Overall, our results show that online terrorism research has a vivid agenda, which reflects global and national trends. The gap between core terrorism and computer science journals, and between funded and unfunded research, heralds at least two developments in the near future: 1) we may see the emergence of specialized journals in the terrorism field that focus on terrorism and concepts like social media, populism, hate speech, text mining, machine learning, and so on; and 2) there may be more collaborative outputs between terrorism researchers and computer scientists.


Dr. Kamil Yilmaz is a Post-Doctoral Researcher at Cyber Threats Research Centre (CYTREC), Swansea University.

Image credit: Pexels

Want to submit a blog post? Click here.

Leave a Reply