Stam's research has examined the relationship between democracy and war, leadership dynamics, and the Rwandan genocide and civil conflict. His work on war outcomes, mediation, and alliance politics has been published in political science journals and books, and he has received grants, including those for comparative theory testing, interstate wars, and collaborative research on the expected utility theory of war. However, he highlighted that these advantages diminished in prolonged conflicts, and after 18 months of war, autocracies persisted and ultimately gained the upper hand through their military-industrial capacity and strategy. In 1999, he published
Win, Lose, Or Draw: Domestic Politics and the Crucible of War. He argued that war outcomes are shaped not only by resources but, crucially, by domestic politics and strategy choice. Subsequently, in 2002, he co-wrote a book titled
Democracies at War, which Brandon Valeriano described as "an important empirical contribution to the fields of political science and military strategy."
Leaders and leadership Stam's 2005 study documented that older leaders were likelier to initiate and escalate militarized disputes, particularly in democracies and intermediate regimes, excluding personalist regimes. He found that leaders with military service and former rebels were more likely to initiate militarized disputes, while combat veterans did so mainly in weak civilian regimes. He further emphasized that leader attributes, particularly combat experience, influenced their military assessments and threat effectiveness in international conflicts. In his book,
Why Leaders Fight, he explored how national leaders' life experiences and personal traits shaped their decisions on war and peace.
Kirkus Reviews stated that the book was willing to challenge tradition without using "strident rhetoric." They further added, "This is a valuable contribution to the study of leadership and international relations in general." In 2004, he co-authored
The Behavioral Origins of War, which Philip A. Schrodt praised as "potentially the last important one," and Lawrence D. Freedman noted that the authors "offer an ever more refined analysis."
Rwandan genocide and civil war Stam served as co-principal investigator for a National Science Foundation-funded Genocide and Resistance project in Rwanda. Between 1998 and 1999, while working with the
U.S. Agency for International Development, he and his colleagues assessed the 1994 genocide, which may have claimed 1 million lives. He and his collaborator, Christian Davenport, gathered data from the
National University of Rwanda, conducted surveys, and interviewed government elites. Despite documenting the genocide, he was labeled a 'genocide denier' by the Rwandan government. In addition, he collaborated with both the prosecution and defense at the
International Criminal Tribunal for Rwanda and uncovered data from NGOs documenting the 100 days of violence. He underscored that various forms of political violence occurred simultaneously and involved both the Hutu government and the Rwandan Patriotic Front, with the majority of victims likely being Hutu. Furthermore, his findings revealed that killings occurred nationwide with varying rates and magnitude, and a comparison of the 1991 census with violence data suggested that over half of the 800,000–1 million killed were Hutu, challenging the view that genocide was the sole motive. ==Awards and honors==