Atran has experimented on the ways scientists and ordinary people categorize and reason about nature, on the cognitive and evolutionary psychology of religion, and on the limits of rationality in understanding and managing deep-seated cultural and political conflict. His work has been widely published internationally in the popular press, and in scientific journals in a variety of disciplines. He has briefed members of the US Congress and the National Security Council staff with documents and presentations including "The Devoted Actor versus the Rational Actor in World Conflict", "Comparative Anatomy and Evolution of Global Network Terrorism" and "Pathways to and from Violent Extremism". He was an early critic of U.S. intervention in Iraq and of deepening involvement in Afghanistan. In April 2015, he addressed the United Nations Security Council on "Youth, Peace, and Security."