Online and Offline Effects of Terror Attacks on Public Opinion

In recent decades, Europe and the Middle East were targeted by of a wave of Islamist terrorist attacks, sparking intense debates on immigration in politics and the media. Yet, the evidence on how terrorist attacks affect citizens’ attitudes remains inconclusive. Studies examining political attitudes in surveys have found no consistent evidence of significant effects of terror attacks. Conversely, studies investigating public discourse in online social media suggest an increase in toxicity and ethnic insults following terror attacks.

We argue that, in order to understand different reactions to terrorist attacks in surveys and online media, we have to consider how political actors create narratives around symbolically significant events. To provide such a comprehensive overview, we first analyze data from three terrorist attacks that occurred during the ongoing Gieldwork of the European Social Survey (ESS). We focus on questions on attitudes towards immigration to trace the effect of terror attacks on the attitudes of representative population samples. Second, we collect data on YouTube videos discussing immigration-related topics. We use text sentiment as proxy for attitude expression in text, evaluating whether terrorist attacks lead to a shift in attitudes expressed in YouTube comments.

The preliminary results on the ESS data indicate that, on average, terror attacks are followed by a statistically significant decrease in attitudes towards immigrants. Our initial findings from the social media data suggest that terror attacks are associated with a significant increase in the number of comments expressing negative immigration attitudes. Yet, we find no evidence of an increased tendency of individual comments to express such negative attitudes after the attacks.

Our study helps disentangle the differences in attitude changes in online platforms and survey studies. Our results can help understand how the attitudes of different segments of society towards immigration are affected by terror attacks.