Historian Richard Overy, an honorary professor at the University of Exeter, dives deep into the unsettling question of why humans wage war. He illuminates the psychological and historical roots of conflict, exploring the 'us vs. them' mentality that fuels division. Overy examines the interplay of resources, belief, and ideology, asserting that warfare is a collective, not just individual, motivation. He also discusses the economic foundations of empire and critiques historical missteps in diplomacy, offering a nuanced look at the complexities behind war.