InFocus – Who is susceptible to the call of political violence?

A study of differential susceptibility and situational resistance to exposure to online violent extremism.

Exposure to violent extremism

One hotly debated issue in contemporary research on politically and/or religiously motivated violence is the issue of ‘differential susceptibility’ versus ‘situational resistance of exposure to extremism’, both in real life and through social media.[1],[2] The basic idea is that individuals who are susceptible will be influenced differentially to commit politically or religiously motivated violence, depending on their level of exposure to extremist content. Situationally immune individuals are sufficiently protected against negative influences such as exposure to extremist content via social media or online exposure to violent extremism. In criminology, the idea of differential susceptibility is acknowledged in different frameworks (see Wikström & Bouhana, 2016). The issue of differential susceptibility has a long tradition in developmental and social psychology.

The study of politically motivated violent crimes is interdisciplinary and has a long tradition in political sciences (for overviews see Koehler, 2017), criminology (e.g. LaFree & Freilich, 2017) and psychology (e.g. Bandura, 1990; Borum, 2004; Davis & Cragin, 2009). Contemporary scholars of political/religious violence discuss the importance of exposure to extremist content online (e.g. using social media). Akin to the heated debate on the relation between exposure to aggression in playing (video) games and aggressive behavior, the discussion on the impact of exposure to online extremist content takes different forms. Several learning theories are often used to explain the effects of exposure to aggression. One of the first influential models was the Social–Cognitive Model of Albert Bandura, who also stressed the importance of attitudes and extremist beliefs on the commitment of atrocities like acts of terrorism (Bandura, 1990). Some scholars hypothesize that there is a strong causal relationship between an individual’s exposure to extremist content and the individual committing political/religious violent crimes (Akers & Silverman, 2004), while other scholars argue that online exposure is a matter of selection effects (King & Taylor, 2011; Klausen, 2015). Selection effects occur when people self-select (or choose) to build their own niches. Few studies have examined interaction (i.e. amplification) effects as a viable explanation for the moderate-sized main effects of measures of exposure to extremist content through social media and self-reported acts of crime, committed to obtaining political or religious goals (Schils & Pauwels, 2016). As crime is a legal construct (i.e. a summary of what is prohibited by law in a given jurisdiction in a certain time window), we have decided not to focus on this heterogeneous phenomenon of crime[3] and to connect with the social-psychological research tradition focusing on aggression, namely political aggression (Allen & Anderson, 2017). After all it is aggression, and the most severe forms of, namely seriously violent acts which affect our (biased) perceptions of fear of crime.

Aggression and violence are often used synonymously in the fields of political science and criminology, but in social psychology, violence refers to the most serious acts of aggression, i.e. behavior intended to cause harm (whether or not attempted or succeeded). Intentionality, harm and the avoidance of harm by the target are what distinguishes aggression from other behaviors that may be antisocial or may involve the breaking of conventional norms. Most scholars in the ‘political violence and illegal political protest’ research tradition as well as scholars in the ‘violent extremism’ and ‘terrorism’ literature seem to agree on the fact that the internet and social media can function as an echo room and that social media and the internet play an important role in recruiting members of extremist groups (Amble, 2012; Awan, Hoskins, & O’Loughlin, 2011; Klausen, 2015; Roversi, 2008).[4] Much of the debate is however not based on large-scale empirical studies but either on in-depth analyses of narratives of terrorists (Moghaddam, 2006; Speckhard, 2012) and case studies of suicide bombers (e.g. Pape, 2005). We encourage these kinds of in-depth studies as they provide very valuable information on terrorists’ motives and help to reconstruct the life histories of these individuals. However, large scale studies in general populations are somewhat lacking, although both quantitative and qualitative studies of political aggression are needed to enhance our understanding of the mechanisms that affect the commitment of politically violent acts.

A large-scale web survey of young adults in Belgium

Recently, we studied the interaction between specific measures of endorsement of extremism (e.g. endorsement of religious, left-wing or far-right extremism), thrill-seeking, and active online exposure to extremism via social media with regard to the explanation of politically and/or religiously motivated aggression (see also Schils & Pauwels, 2016; Pauwels & Schils, 2016). While the relationship between exposure to crime-prone contexts and aggression has been studied widely, no previous study has explicitly demonstrated the conditional effects of these factors in a survey of young adults and with regard to political aggression. Our study is inspired by the General Aggression Model, a well-established theory of aggression and the Situational Action Theory, a recently developed theory of crime causation. The unique contribution of our study is that it is based on distinctive measures of endorsement for extremism (left-wing nationalist/separatist and religious extremism) and that it focuses on the differential effect of exposure to extremist content online. We made use of a large-scale web survey of young adults in Belgium where 6,020 respondents completed the online questionnaire. The mean age (range, 15-31 years) was 20.19 years, and 35.3% of the sample were males. The results support an amplification effect: endorsement of extremism is related to self-reported political aggression but its effect increases by levels of active social media exposure. The results additionally showed that (1) there is no relationship between endorsement of left-wing, right-wing and religious extremism in individuals scoring low on thrill-seeking, (2) there is a moderate relationship positive between endorsement of left-wing, right-wing and religious extremism in individuals scoring averaged on thrill-seeking, (3) there is a strong positive relationship positive between endorsement of left-wing, right-wing and religious extremism in individuals scoring high on thrill-seeking. We illustrate these findings for the relationship between endorsement for religious extremism, political aggression and thrill-seeking.

These findings are rather stable across extremism-specific measures of endorsement of extremism. This study adds to the growing body of literature demonstrating a statistical interaction between the endorsement of extremism and the online exposure to its narrative. The relationship between exposure to extremist content and self-reported aggression remains however controversial, not only from theoretical and empirical perspectives but also from a policy perspective. We are limited in deepening this discussion here but we can refer to the debates regarding the effect(s) of exposure to violent video games. In short, such studies have shown mixed results, and those studies that do show significant effects of exposure reveal small statistical effects. This study shares a similarity with the more conventional studies of exposure to criminogenic ‘violent’ contexts. We studied the effect of exposure to extremism, albeit from a completely different angle consisting of exposure to extremist content (online). The basic idea was to discover similarities or differences in the processes leading to the act of political violence. Our study contributes to the literature by showing that exposure to extremist content is not related to political violence when individuals are sufficiently protected by both their morals and their level of thrill-seeking. But when self-control decreases, the effect of exposure to extremist content on the relation between endorsement of right-wing, left-wing or religious violent extremism and political violence becomes stronger.

Key questions and future studies

There are several key questions that remain under-researched thereby deserving further inquiry. They are (1) how do individuals acquire their endorsement to extremism?, (2) how stable are these attitudes through the life course?, and (3) how stable are these interactive patterns across different phases of development? We have studied a large sample of young adults, but the research should cover the course of an individual’s life. Sometimes individuals radicalize much later in life and some have a history of deviance. However, sometimes adults radicalize without any developmental history of externalizing behavior. If we really want to take developmental tests of the processes of radicalization (and disengagement) seriously, panel data can be of high value. Young adolescents and even children have been drawn to areas of conflict because of a fast process of radicalization, thus, we need to increase our understanding of the differential susceptibility of several age groups to different kinds of exposure. The power of radical messages online and offline and the powerful discourses brought about by recruiters should neither be overestimated or underestimated. Small effect sizes in studies often lead to underestimating, but we argue that overall small effect sizes are related to differential susceptibility. Different age groups represent different phases in the life-course and thrill-seeking is especially higher in adolescents than in older populations. This suggests a plausible explanation for the vulnerability of adolescents. However, what makes adults suddenly develop attitudes favorable to extremism? And how is the process of disengagement, i.e. the process of desistance brought about?

Future studies should try to improve sound integrative theories analyzing all mechanisms involved in the explanation of political aggression as well as the processes that lead to the development of endorsement of extremism. They should also address the factors leading to exposure to extremist content, which is likely caused by a combination of social influence (peer influence of members of extremist groups), social selection (i.e. urban segregation, which causes recruiters to target some areas more than others), and self-selection (i.e. processes of perception and choice, caused by a sense of belonging or similar human motives). In other words, it is of major importance in terms of theory and policy to disentangle the so-called ‘causes of the causes’ of political aggression to further enhance our understanding of how grievances and weak social integration gives rise to political powerlessness, alienation from wider society and the development of endorsements of nationalist-separatist, religious or left-wing extremism. While these attitudes and beliefs are different, the interactive processes that produce political aggression, as an outcome, seem to be highly similar. There is an urgent need to develop a critical test of propositions derived from truly interdisciplinary integrative theories that incorporate elements of cognitive neurosciences, cognitive psychology (beliefs), sociology and geography (exposure to settings). Some disciplines will be more useful in explaining some of the ’causes of the causes’ of violent extremism, while others will be more useful in explaining direct and situational causes of violent extremism. Our personal experience is that this kind of theoretical integration will require scholars to learn each other’s language, but once this barrier has been overcome, challenging new research strategies can be facilitated.

Policy implications for the prevention of political aggression

What do these results suggest with regard to the prevention of online radicalization into extremism? This study suggests that exposure to extremist content strongly triggers the endorsement of extremism for individuals, while the magnitude of the effect of exposure to extremist content on self-reported political violence is further amplified by levels of thrill-seeking. This means that of primary concern are complex interactions between individual and circumstantial characteristics. Websites and social media platforms visited by adolescents differ in nature as well as in persuasiveness of extremist content. Their content is sometimes very provocative and tempting which, triggers an emotional reaction and affects attitudes, as well as norms (Ramsay, 2013; Roversi, 2008). Some virtual settings give very easy access to extremist content and pose a dangerously real potential for further recruitment into extremist groups or for preparing attacks in the form of ‘home-grown violent radicalization.’ Although extremists might be trying to spread hate and induce polarization in mainstream virtual settings (such as chat rooms and web fora for a general audience), these mainstream settings are not extremist in nature. While closing down these general fora is not very effective in the prevention of violent extremism, extremist content which is polarizing should be removed to avoid further escalation. Governments should support the removal of extremist content on mainstream social media and fora.

Adolescents in an early stage of radicalization may also visit websites or YouTube channels containing explicitly extreme content or join extremist groups on social media in search of plain answers to complex problems related to social identity, (perceived) injustice, and so on. Closing down hard-core extremist websites is necessary for governments to give a clear signal that it is intolerant of the intolerable. However, these measures will never be effective when they stand by themselves. Situational prevention of political aggression, violence or ‘violent extremism’, which is today’s buzz-word in policy circles, should always be considered in close relation to social prevention. The main question remains which concerns why individuals become who they are, i.e. (1) why they develop a justification for the use of violence to obtain political goals, (2) why they lost their social ties to society and became increasingly susceptible to extremist content via online and offline sources from recruiters, and (3) who target the most vulnerable individuals.

Furthermore, there has been a lot of talk about the use of counter narratives for the prevention of online radicalization (see also Leuprecht, Hataley, Moskalenko, & McCauley, 2010). We hold that the role of counter-narratives should not be overestimated. Some scholars have argued that the use of the concept ‘counter-narratives’ is not useful and that alternative narratives are a better way of dealing with the prevention of violent extremism: The focus should move from counter-narratives to alternative narratives which provide strong and positive arguments (Weilnböck, 2013). The effect of such measures depends on the number of individual characteristics. Individuals with low levels of thrill-seeking may be sufficiently protected against the effect of endorsement of extremist ideologies, exposure to extremist content and their interaction on political aggression. Individuals who have very low scores on the thrill-seeking measurement caliber may be more easily convinced by being provided information on the unintended consequences of making wrong choices, i.e. through identifying the results of a Benefit-Cost analysis of political aggression. Individuals who score high on thrill-seeking measurement caliber experience an amplification effect: In this group, the effect of endorsing extremism is triggered by levels of exposure. Thrill-seeking pulls some individuals towards extremist groups.

Consequently, these highly susceptible individuals may be especially difficult to convince to abide by the law with (online or offline) rational narratives alone. Online narratives will have lesser impact if the real-life circumstantial characteristics are not addressed simultaneously. The prevention of endorsing extremism, be it on the left-wing, right-wing or religious wing, will be easier to facilitate by developing interventions that reorient moral endorsement (e.g. through education and cognitive behavioral therapy) and cognitive nurturing (e.g. learning to overcome proneness to thrill-seeking), akin to that in developmental crime prevention. In this study we have not addressed the problem of the causes of the causes, i.e. why and how (events and processes) some individuals develop their grievances. However, several empirical studies have pointed to the role of grievances, group processes and alienation (e.g. Doosje et al., 2013).

Some individuals may engage in aggression habitually because behaving violently may have provided rewards to the actor as a means to solve problems encountered in life, or because they have been raised in disadvantageous ecological contexts. Here, social prevention is important and this prevention can be achieved by removing at-risk individuals from certain ecological contexts where they are repeatedly provoked or tempted. It is important that the prevention of political aggression has a profound knowledge-base and that it takes an analytical approach to prevent problems of the day being from being solved with ‘measures of the day’ (Wikström & Treiber, 2016). We hope that this study, which demonstrates the complexity of political aggression, may set a paradigm for interventions by analytically looking at the problem of political aggression.

The Authors

Lieven J.R. Pauwels is a professor of criminology at the Department of Criminology, Criminal Law and Social Law at Ghent University, Belgium. He is Director of the Institute of International Research on Criminal Policy (IRCP). He is interested in a developmental-ecological approach to juvenile delinquency, violent extremism, and knowledge-based (crime) prevention.
Wim Hardyns is a professor of criminology at the Department of Criminology, Criminal Law and Social Law at Ghent University, Belgium. He is a member of the Institute of International Research on Criminal Policy (IRCP). His current interests are crime mapping and statistics, environmental criminology, crime prevention, new security technologies, big data, radicalization, and terrorism.


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[1]     This article is a summary of our study that is published in the thematic issue “Developmental Pathways Towards Violent Left-, Right-Wing, Islamist Extremism and Radicalization” of the International Journal of Developmental Science. For the full-text of our study, see: Pauwels, L. & Hardyns, W. (2018). Endorsement of extremism, exposure to extremism via social media and self-reported political/religious aggression. International Journal of Developmental Science, 12, 51–69.

[2]     We would like to thank Belgian Science Policy (BSP) and the Belgian Ministry of the Interior (IBZ), who co-financed this research project to get insight in the relationship between exposure to extremist content and politically/religiously motivated aggression. A first research report was published as (Pauwels et al., 2014). We have complied with Helsinki Ethical Declaration in the treatment of our data.

[3]     Leading contemporary criminologists argue that the study of causes of crime is hampered by the heterogeneity of definitions, and suggest as a solution to this problem that it is more worthwhile to try to explain why people break rules, stated in law, knowing the sanction is possible. The rule-breaking element is what all crimes have in common, according to some criminological research traditions (Wikström & Bouhana, 2017). Definitional problems have challenged criminology for a long time (Agnew, 2011).

[4]     In this contribution we do not pay attention in separate paragraphs to the problems of defining violent extremism and terrorism, as a myriad of definitions exist. Radicalization is a complex process of incrementally experienced commitment to extremist political or religious ideology. For an overview of definitions of radicalization processes we refer to Horgan (2005) and Koehler (2017). For an overview of the relationships between extremism and terrorism we refer to Schmid (2011).