Preliminary Assessment of the Interaction of Collectivism and the Heat–Aggression Relationship in Terrorism

Objective: The relationship between heat and aggression is robust for different types of aggressive acts and has been recently extended to terrorism, providing another avenue when examining causes and environmental contributors to political violence. The present study describes a preliminary investigation of the role that cultural factors, such as collectivism, may play in the heat–aggression relationship as it pertains to terrorist attacks. Method: Country-level terrorism data from 1970 to 2015 and monthly average temperatures across the same timeframe were integrated with individualism/collectivism ratings from Hofstede’s IBM studies and the GLOBE studies and analyzed with zero-truncated negative binomial regression models. Results: The results indicated that societal in-group collectivism significantly interacted with temperature and counts of terrorist attacks, with higher ratings of in-group collectivism associated with weaker associations between temperature and terrorism. Other collectivism constructs, such as Hofstede’s individualism–collectivism index and institutional collectivism, did not interact with temperature and terrorist acts. Conclusions: The findings provide initial evidence of the role cultural factors may play in shaping the temperature–aggression relationship as it pertains to terrorism, which may be a major consideration as societies continue to be negatively impacted by climate change.