Recent years have seen a rise in political polarization across many Western democracies, with the British public displaying some of the highest levels among OECD countries. At the same time, terrorism remains a significant concern for UK citizens. But how do these two phenomena interact? Our recent study, published in The Journal of Politics, reveals that terrorist attacks can significantly influence affective polarization – the extent to which citizens hold positive feelings for their preferred party and negative feelings for opposing political parties. However, the impact varies dramatically depending on the nature of the attack.
Our research demonstrates that Islamic terrorist attacks increase affective polarization among the British public, while far-right terrorist attacks tend to decrease it. These contrasting effects stem from fundamental differences, such as these attacks. Minority groups typically carry out Islamic terrorism, which is driven by religious extremism, and often targets random civilians, potentially affecting everyone in the society. In contrast, right-wing terrorism is usually perpetrated by white men endorsing white supremacism, ethno-nationalism, and anti-immigrant sentiments and targets specific minority groups or individuals perceived as threats to the attackers’ cultural or racial identity. Because of these differences, debates over polarizing issues become more intense in the aftermath of Islamic attacks as individuals seek solutions to mitigate the risk of becoming victims of future attacks. This can amplify the salience of rival political positions and increase perceptions of politics as sharply divided. At the same time, a cultural backlash against immigrants can only be activated by Islamic terrorism, contributing to the divisive debate on the link between terrorism and border control or the social assimilation of immigrants. In other words, the potential for unity in the wake of Islamic attacks is overshadowed by heightened out-group hostility and support for divisive policy responses, ultimately increasing polarization. Conversely, far-right attacks primarily activate mechanisms that unite the public, which tend to reduce polarization.
Analysis of recent attacks and key findings
In our study, we analyzed four major terrorist incidents in Great Britain between 2016 and 2019: two far-right attacks (the murder of MP Jo Cox on June 16, 2016; and the Finsbury Park attack on June 19, 2017) and two Islamic attacks (the Manchester Arena bombing on May 22, 2017; and the London Bridge stabbing on November 29, 2019). Using data from the British Election Study (BES), we compared responses from individuals interviewed shortly before and after each of the attacks. This allowed us to measure the causal effect of terrorism exposure on affective polarization.
Our findings demonstrate that Islamic attacks increase affective polarization by about 0.09 units on a 0-10 scale, while far-right attacks decrease it by about 0.17 units. To put this in perspective, after an Islamic attack, approximately half a million more people exhibit high levels of affective polarization. Conversely, following a far-right attack, approximately 1.3 million more people show lower levels of polarization.
How different types of terrorism affect polarization
There are several explanations for why Islamic and far-right attacks induce different affective reactions. The first explanation is based on the perceived salience of terrorism. Islamic attacks are more likely to be framed as major threats to national security, whereas far-right attacks are often portrayed as isolated incidents committed by troubled individuals. Our analysis shows that the probability of reporting terrorism as the most important national issue increases by 24 percentage points after an Islamic attack – nearly five times the increase observed after far-right attacks.
The second explanation has to do with the type of debate that terrorist attacks stimulate and the resulting changes in attitudes about immigration. Previous studies have documented that Islamic extremism tends to increase nationalism, anti-immigrant sentiment, and hostility towards out-groups among the native population. After a far-right attack, however, citizens may soften their feelings towards immigrants to avert any association with the ideology of the perpetrator and rally behind shared values of acceptance and inclusivity.
To investigate how the perpetrator’s identity affects immigration views, we analyze Twitter data to assess the emotional content of immigration-related tweets around the dates of four selected attacks. Figure 1 shows the average levels of anger, sadness, and fear before and after each attack. Negative emotions rise notably after the two Islamic attacks—especially fear and sadness, with some increase in anger. In contrast, following the two far-right attacks, fear decreases, and sadness rises only slightly.
Figure 1: Emotional scores for tweets on immigration: anger, sadness, fear. Vertical lines in the middle of the bars signify the 90% confidence interval.
Similarly, our analysis of BES data confirms that exposure to terrorism perpetrated by far-right extremists sways the population towards a more pro-immigration stance.
The third explanation is related to the political rhetoric surrounding these attacks. Right-leaning parties often exploit Islamic attacks using ‘natives’ versus ‘non-natives’ rhetoric, which can intensify feelings towards parties on the two sides of the political debate. After far-right attacks, however, parties supporting far-right ideas are forced onto the defensive, and politicians across the spectrum unite in condemnation, potentially reducing interparty hostility – there are parallels here with the summer 2024 riots where members from all sitting parties deplored the violence. Our analysis provides evidence of these opposite effects, showing that far-right terrorist violence, despite its tragic and destructive nature, can lead to a public rejection of extreme ideological positions as citizens distance themselves from the perpetrators’ beliefs.
Overall, our findings suggest that Islamist extremists may be more successful in their goal of sowing division among the population, while far-right extremists produce the opposite effect. This underscores the need for nuanced, tailored responses to different types of terrorist threats. Policymakers and media outlets should be aware of how their framing of terrorist incidents can influence public opinion and societal cohesion.
Authors
Vincenzo Bove is a Professor of Economics at IMT School for Advanced Studies Lucca.
Riccardo Di Leo is a Research Fellow at the European University Institute.
Georgios Efthyvoulou is a Senior Lecturer in Economics at the University of Sheffield.
Harry Pickard is a Lecturer in Economics at Newcastle University.
https://www.journals.uchicago.edu/doi/abs/10.1086/732969?journalCode=jop