Have humans evolved psychological adaptations to war? This question has generated major scientific debate involving anthropologists, archaeologists, economists, primatologists, psychologists, and political scientists. It has shaped popular perceptions of human nature and influenced the views of political leaders. Observing the limits of archaeological, ethnographic, and comparative evidence, I posit that only evidence of special design, obtained from an integrated program of psychological experiments, can conclusively answer this fundamental question. If humans are adapted to war, then human psychology must be equipped with specialized adaptations designed for the effective navigation of war: planning, executing, and defending against coalitional attacks. AWAR probes the existence of such adaptations. It focuses, specifically, on coalitional formidability assessment mechanisms, which likely helped ancestral humans to avoid costly fights. Such mechanisms, if revealed, likely constitute “smoking-gun” evidence that war shaped human evolution. AWAR also explores real-world implications of coalitional formidability assessment mechanisms: if they indeed exist, do they shape our attitudes and behavior today, particularly in the context of modern political violence (e.g., violent anti-government protests and armed civil conflicts)? AWAR presents the first elaborate information-processing model of a coalitional formidability assessment mechanism. In turn, it conducts an integrated program of 20 lab experiments and surveys in 40 countries. Crucially, AWAR holds the potential to reveal the existence of a psychological adaptation in humans, contributing to the growing efforts to map the universal architecture of the human mind. The project’s results will likely appear in major multidisciplinary journals, advancing scholarly debates in at least six disciplines. Most importantly, AWAR breaks new ground for a novel perspective in the study of modern domestic political violence.