🔍 Mechanisms: We find conflict exposure increases negative perceptions of out-groups, authoritarian attitudes, and aggressive tendencies. All these changes persist 10-25 years after service, showing the long-lasting impact of war on intergroup relations. ⏳

⚔️ Combat Experience Matters: The effects are driven by direct combat exposure (DCE). Veterans with combat experience donate show strong parochial preferences, highlighting how traumatic experiences shape social preferences.

📊 Main Results: Conflict exposure significantly reduces donations to out-group members. No significant effect on in-group donations, suggesting conflict increases parochialism mainly through out-group derogation rather than in-group favoritism. 💰

💭 Theory: War may transform social preferences in a parochial way - strengthening in-group cohesion while increasing out-group hostility. But which channel dominates - increased in-group love or out-group derogation? 🤝 Our design lets us test this directly.