The Invisible Scars of Terrorism
Can a terrorist attack permanently alter the way we view others and live in society? According to a recent study, published in Economic Development and Cultural Change, which I conducted with Elisa Borghi and Francesco Scervini, the answer is yes. Terrorism leaves deep scars on the personality: events experienced during the formative years of life (adolescence and early adulthood) influence trust in others even decades later. The study's findings, which highlight the long-term effects of terrorism on social capital, appear particularly significant when interpreted in light of today's global context, increasingly marked by insecurity and polarization. We cross-referenced data from the World Values Survey, which measures interpersonal trust, with data from the Global Terrorism Database, which records terrorist attacks and victims of acts of terror worldwide since 1970. The analysis is based on a sample of over 210,000 individuals interviewed in 107 countries, born between 1954 and 1993.
The core of the research is the psychological hypothesis of the ‘impressionable years’ model, according to which values and attitudes are formed primarily between the ages of 15 and 25, when personality is most flexible and social experience is most intense. It is in this crucial stage of life that we construct what psychologists call the emotional maps through which we interpret the world. Collective experiences of fear or violence, experienced during these years, tend to become embedded in an individual’s emotional memory and have a lasting influence on our perception and trust of others. It is precisely during this period that traumatic events such as wars, economic crises, natural disasters or terrorist attacks can leave a profound and lasting impact on one's perception of society and interpersonal relationships. The analysis shows that those who lived in countries affected by attacks through their impressionable years, as adults tend to trust others less. This effect is not observed when exposure to these events occurred in childhood or adulthood, confirming that the impressionable years are precisely the window of time during which individual values are consolidated.
The study's results show that this is not a transient effect: even controlling for age, income, education, religion and country characteristics, the impact remains statistically significant. The loss of trust increases with the frequency and severity of attacks: being exposed to a greater number of events or to more lethal events increases the perceived sense of insecurity. The passage of time does not help erase these effects: the collective memory of the years of terror continues to influence the generations who lived through them, modifying behaviors and expectations towards others. The political context, however, is crucial, as is the nature of terrorist events. Both domestic and international terrorism reduce interpersonal trust, but to varying degrees. International attacks produce a more pronounced and persistent effect, while domestic attacks are perceived as part of internal conflicts and, therefore, in some cases, can even generate temporary group cohesion.
The overall impact of both types of terrorism is, however, stronger in authoritarian countries than in democratic regimes. In more democratic countries, institutions appear capable of mitigating the loss of trust: civic cohesion, freedom of the press and the ability of authorities to respond transparently help rebuild social bonds. Conversely, in authoritarian or fragile regimes, attacks deepen mistrust and amplify divisions.
In an era marked by a global decline in the trust placed in institutions, the media and even fellow citizens, understanding how traumatic shocks influence its formation is essential to developing effective policies to rebuild social capital. Trust is a fragile but crucial collective asset: it reduces transaction costs, fosters cooperation, and supports economic growth and democratic stability. After an attack, it's important to focus on adolescents and young people to avoid long-term negative effects. Terrorism doesn't just destroy lives or infrastructure: it erodes the invisible fabric that holds societies together. Rebuilding it requires time, awareness and strong institutions. In times of fear and uncertainty, nurturing trust is not only a moral objective: it is a necessary condition for the democratic and economic health of societies.
