The Islamist attack near Berlin’s Christopher Street Day on 25 July 2026 killed one person and injured 29 others, some seriously. According to current reporting, the attacker was a 21-year-old German citizen, born and raised in Berlin, whose parents had immigrated from Lebanon. He was known to the authorities as an Islamist extremist and had previously been convicted of attempting to join the so-called Islamic State. He was killed during a police operation the following day.
This article was initially written in the immediate aftermath of the attack, when the number of victims, the attacker’s identity and citizenship, the precise motive and the possible involvement of others were still unclear. It has now been updated as the emerging facts substantially change how the event should be discussed.
The attacker was not a recently arrived migrant or a refugee who entered Germany to commit violence. He was a German citizen who grew up in Berlin and appears to have radicalised within German society. Nevertheless, right-wing populists quickly used the attack to call for a “migration reversal” and blamed Germany’s immigration and naturalisation policies. In its official response, the Alternative für Deutschland explicitly linked the attack to what it called decades of naïve immigration and naturalisation policy.
This reaction is analytically revealing: even when an attacker is German, his parents’ origins can be used to redefine him as a migrant and turn an individual act into an accusation against immigration as a whole.
What my research actually found
For another EPIS Think Tank magazine article on humanitarian and non-humanitarian migration and international terrorism, I analysed data from OECD countries covering the years 1995 to 2018. I distinguished between humanitarian migration – particularly refugees and asylum seekers – and non-humanitarian migration for purposes such as employment, study or family reunification.
A simple statistical model initially suggested that the two forms of migration might have different associations with international terrorism. A more rigorous fixed-effects model, however, did not confirm that result. The implication is important: my analysis established neither a stable causal effect nor a strong ability to predict terrorist attacks from migrant numbers. Instead, it demonstrated how cautiously the migration–terrorism relationship must be interpreted.
The ‘Trojan horse’ narrative falls short
An important foundation of my research was Sara M. T. Polo and Julian Wucherpfennig’s (2022) study ‘Trojan Horse, Copycat, or Scapegoat?’. It challenges the widespread assumption that larger refugee movements automatically allow terrorists to enter developed host countries as a ‘Trojan horse’.
The authors find no robust evidence that hosting refugees in developed countries increases imported terrorist attacks against host-country nationals. They also show that refugees themselves may become targets of retaliatory terrorist violence.
The Berlin attack does not fit into the ‘Trojan horse’ narrative. The attacker did not arrive through a recent refugee movement. His German citizenship, upbringing in Berlin and previous contact with German institutions point instead towards domestic radicalisation and possible failures in dealing with a known extremist.
His family’s Lebanese background may form part of his biography, but it does not explain why he embraced violent Islamism. Treating ancestry as the decisive factor distracts from more immediate questions: How did a young man raised in Germany become radicalised? What role did extremist networks, online propaganda or personal crises play? Why was a person already known to the authorities able to carry out such an attack?
Integration is part of security policy
Radicalisation has no single cause, and there is no universal terrorist profile. Social isolation, discrimination, personal crises, extremist propaganda, limited prospects and contact with radical milieus may reinforce one another. The overwhelming majority of people experiencing such conditions never become radicalised; these are possible vulnerabilities, not predictions (see e.g. Piotr Zagórski et al., 2024 or Natalia Del Pino-Brunet et al., 2021).
Nevertheless, this perspective makes integration relevant to security policy. Access to language learning, education, employment, psychosocial support, stable housing and social participation can reduce isolation and strengthen a sense of belonging. Family reunification may also help create a more stable social environment, although its precise effect on radicalisation requires further research (see Yayla, 2021 and Treistman, 2024).
Germany has recently moved in the opposite direction in several areas. Family reunification for beneficiaries of subsidiary protection was suspended for two years from July 2025, while access to integration courses was temporarily restricted for several groups in early 2026 (a limited, quota-based reopening was subsequently announced in June 2026). These policies did not cause the Berlin attack. Claiming such a direct connection would repeat the same analytical error as blaming migration itself. Yet weakening opportunities for participation may increase vulnerabilities that prevention policies should seek to reduce.
The right lesson from Berlin
The attack demonstrates neither that migration is irrelevant to security nor that restrictive migration policies automatically make societies safer. It shows that terrorism emerges from complex individual, social, political, and transnational processes.
Security authorities must identify concrete threats, dismantle extremist networks and examine why a known Islamist was able to remain free. At the same time, political debate must resist turning citizenship into an ethnic category. A German citizen does not become a migrant whenever his parents were born elsewhere.
After an Islamist attack, determined law enforcement and honest debate are essential. But using the tragedy as evidence against migrants in general obscures the actual security failures, deepens social divisions and reinforces the fear and polarisation that terrorism seeks to create.
