Nationalism and Conflict: Lessons from International Sports

Does nationalism make interstate conflict more likely? Many believe so, arguing that it led to conflicts such as the Spanish-American War, the two World Wars, and Russia's recent intervention in the Ukraine. However, others contend that strategic constraints greatly limit the effects of nationalism on state behavior. Resolving this debate has proven difficult because of endogeneity and measurement issues. I overcome these problems by analyzing one of the most powerful sources of nationalism in the modern era-international sports. I first investigate several cases in which surges of nationalism from sporting events led to military or political conflict between countries. I then analyze a regression discontinuity created by the format of the World Cup qualification process from 1958 to 2010. The results provide strong evidence that World Cup nationalism increases state aggression, especially for countries where association football (soccer) is the most popular sport. I also explore a case from the dataset-Senegal in 2002-to illustrate how World Cup nationalism led to a specific dispute in my sample.