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Aktualisiert: 24. Okt. 2023

The recently convicted terrorist Khairi Saadallah referred to his triple murder by knife in a Reading park as the „jihad that I done“. Saadallah was a denied asylum seeker, with a history of crime, debt, homelessness and mental problems; his unstable behaviour and anti-social personality disorder were however not sufficient to substantiate a mental illness defence. Already back in the 80s, when terrorism studies were still in their infancy, clinical research on scores of left-wing terrorists in Germany decisively dismissed the “craziness” argument. In fact, eminent scholar Martha Crenshaw wrote in her 1981 piece “The Causes of Terrorism” with reference to psychopathology that “the outstanding common characteristic of terrorists is their normality”. Later research on Islamist terrorists reached similar conclusions. Initial arguments placing lack of integration or low socio-economic status at the core of violent jihadi radicalization processes in Europe eventually gave way to evidence displaying a high variety of socio-economic and demographic profiles. In some cases, it was high levels of education and income that distinguished terrorists, exemplary shown for example in the Glasgow airport attack of 2007 perpetrated by a doctor and an engineer; or in the book „Engineers of Jihad: The Curious Connection between Violent Extremism and Education“.

This pattern of somewhat ordinary existences turning to terrorism seems to have fundamentally changed in Europe. Daesh brought the crime-terror nexus to the fore as illustrated by the infamous message „Sometimes people with the worst pasts create the best futures“. But this is not the whole story. An additional feature that seems dominant especially in non-Daesh attacks of recent years is mental illness. Overall, terrorists who have carried out attacks in Europe in recent years were often criminal, mentally disturbed, un- or underemployed, without perspectives, at times failed asylum seekers or former combatants, acting alone. While some claimed dedication to the cause, some did not, and their motivation to engage in violence seems to be of a rather personal nature. The 7/7 bombers’ ringleader of the attack in London in 2005 claimed in his video to aim at stopping the bombing, gassing, imprisonment and torture of ‘his people’. In the video of the Vienna killer of 2 November 2020, the political message was completely absent. From an individual perspective, much of jihadi terrorism in Europe is not fighting for a political cause anymore, but it is the loser’s redemption.

Across Europe, roughly half of the individuals convicted for Islamist terrorist activity had previous criminal convictions. In our sample of 51 Daesh attacks in Europe between 2014 and 2021 there are 59% of perpetrators with criminal background, out of which 30% related to terrorism; in 53% of the cases the attackers were known to the authorities; out of the cases where information could be found in open-source data 33% were unemployed and only 11% had a white-collar job. 90% of these attacks involved a lone actor, and in 24% of the attacks there were mental health issues. In the sample of 20 non-Daesh attacks for the same period (one Al-Qaeda Arabian Peninsula (AQAP) and the rest without affiliation), there is again a prevalence of 90% lone actor and 45% criminal background. 55% had mental issues.

The Vienna attacker was on parole after a conviction for attempting to join Daesh. He had a marginal part-time job as security staff. The man who killed four people and injured six in a tram in Utrecht on 18 March 2019 was a drug addict, with a history of violence and debt, and about to be evicted from his home. In January this year, the ‘tram terrorist’ stabbed a guard in a Rotterdam prison in the face and neck. The Strasbourg attacker of 2018, who killed five and wounded 11 with a knife, was described as a hardened criminal, convicted for the first time at the age of 13 and with a total of 27 convictions from petty crime to robbery to drug dealing. Also in 2018, a man killed two female officers and a civilian in Liège while being on a one-day parole; before that he killed a former prison mate with a hammer. He was known for his violent behaviour and had convictions for robbery, assault and drug dealing. In 2017, a man stabbed and killed a person and injured six more in a supermarket in Hamburg. He was a failed asylum seeker with drug and psychological problems and about to be deported.

Criminal history, precarious economic circumstances and mental illness alone already challenge established knowledge about the commonality of terrorist backgrounds. This, however, should not lead to the conclusion that poverty, mental illness or crime in any manner cause terrorism. The problems of this deterministic approach remain since it still holds true that the majority of individuals in these situations do not turn terrorists. From a strategic perspective, however, it is apparent how individuals with such backgrounds are the ideal pool for organizational recruitment strategies. The Daesh strategy for Europe does not involve conquering and managing territory or obtaining the support of the population. It is a strategy of provocation and attrition, in which context any action that creates chaos and insecurity, in essence, any act of indiscriminate violence will suffice. From this perspective, it is not important to be able to formally recruit, train and control members – mentally ill individuals are not a liability anymore. Daesh has encouraged the use of everyday objects such as knives or vehicles by virtually anyone. Such actions do not need to be planned in a complex manner or centrally coordinated. And the actor does not need to be particularly well versed in either ideology or warfare. Furthermore, Daesh purposely targeted criminals and painting a picture of joining Daesh as the “good life”.

But there is something even more fundamentally different about many contemporary violent jihadis, namely the loose embedding in ideology and organizations, in some cases even a limited commitment to the political cause. Many attackers in recent years in Europe seem to lack strong affiliations with terrorist organizations and their motivation appears to relate more to individual circumstances rather than world politics.

Only 50.7% of the 71 attacks in Europe between 2014 and 2021 were claimed by a terrorist organization. 22.5% were inspired by or otherwise linked to Daesh, while in 26.7% of the attacks no affiliation could be established. Individual biographies of terrorists often reveal short exposure to ideology, and a superficial uptake of essential ideological and/or religious content. For example the perpetrator of the vehicle ramming attack in Nice 2016 was found to have radicalized very rapidly. Anis Amri, a Tunisian who drove a truck into a crowd at a Christmas market in Berlin in December 2016 had ‘radicalized’ in an Italian prison and consumed drugs on a regular basis. The Vienna attacker of 2020 was assessed as having a rudimentary understanding of religion; according to his deradicalization advisor, he believed that all true Muslims’ prayers will be heard. He doubted himself and did not understand why he continued to be imprisoned in spite of his prayers.

When deciding to blow up a London metro station in 2005, Mohammed Siddique Khan created a rudimentary video in which he stated the rationale for his deed. He described what he perceived as a situation of oppression demanding revenge and immediate restorative action. These political objectives or the political narrative has become very thin in recent years. It is as if the political utility of the terrorist act had lost in importance in the face of individual gain. Illustratively, the Strasbourg attacker is reported to have told other inmates that he was about to either commit a robbery or die as a martyr. Hence, these attacks were not so much about politics, but about oneself: personal redemption, gaining self-esteem, finding a way out, or going down with a blow when all other ways seem to be closed – constellations exacerbated by drug use and mental instability.

This new brand of terrorism shows parallels to amok and suicide and has a high potential for replication. In fact, analysts characterized recent attacks as imitative waves. To illustrate: all 13 non-affiliated attacks between May 2018 and October 2020 were committed by stabbing. Also in the sample of Daesh-affiliated attacks we find patterns: the stabbing in London on 2 February 2020 was followed by a stabbing in France one day later; a stabbing in September 2019 in Milan was followed by another in October in Paris, and another in November in London; an attack by vehicle in France in August 2017 was followed by two in the same month in Spain. January and February 2016 also witnessed stabbings in France and Germany. A few days ago, on 24 April 2021, in an attack not yet claimed, a man stabbed to death a policewoman in the municipality of Rambouillet near Paris after watching jihadi martyrdom videos. His family described him as quiet and not particularly pious; he had been in psychiatric treatment. All 8 unclaimed attacks in 2020 were committed by stabbing.

More importantly, it has become increasingly difficult to differentiate terrorism from amok and suicide. Consider the recent incident in Sweden, when an individual stabbed seven people, severely injuring them. Swedish authorities eventually categorized this incident as multiple attempted murder. Yet terrorism was briefly considered, based on the modus operandi which was similar to other attacks deemed terrorism. The assailant was known to the authorities, among others, for petty crimes.

These developments indicate the need to look more closely at specific aspects of the radicalization process, like mental health or socialization in crime and their role therein. The psychological effects of the pandemic and the strategic orientation of specific terrorist propaganda will also need to be factored in. While basic radicalization mechanisms might be comparable across ideologies and time periods, such contextual factors can influence concrete motivations and types of actions. Mobilization to violence appears to increasingly occur in earlier stages of radicalization or as an outlet for personal problems. This increases the pool of potential terrorist attackers in the long run. More effort should thus be invested in primary and secondary prevention, including by involving relevant psychological and psychiatric expertise.

Acknowledgement: the author thanks Erik Hacker for assisting with data collection.

Dr Daniela Pisoiu is Senior Researcher at the Austrian Institute for International Affairs (oiip) and Lecturer at the University of Vienna. She is active in various working groups and in the Editorial Board of the Radicalization Awareness Network (RAN) and has been researching radicalization, terrorism and extremism in Europe for 17 years.


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