Arturo C. Sotomayor is a Professor at the William J. Perry Center for Hemispheric Defense Studies at the National Defense University (NDU), in Washington, DC.

His areas of interest include civil-military relations in Latin America; UN peacekeeping participation by South American countries; Latin American comparative foreign policy, and nuclear policy in Argentina, Brazil and Mexico. His research analyzes the impact of international socialization, militarization, and denuclearization in three areas: 1) military operations other than war (MOOTW); 2) trans-national and border security; and 3) regional non-proliferation strategies. The unifying thread that runs through his research and writing is the interaction between studies on civil-military relations and international security, and research on the conditions and requirements for domestic order and regional stability in Latin America. His publications have appeared in Security Studies, International Peacekeeping, International Studies Perspectives, Journal of Latin American Politics and Society, Nonproliferation Review, Small Wars and Insurgencies, Global Responsibility to Protect, Foreign Affairs, and other edited volumes. His volume The Myth of the Democratic Peacekeeper: Civil-Military Relations and the United Nations (Baltimore: Johns Hopkins University Press, 2014) was the winner of the 2015 Luciano Tomassini Latin American International Relations Book Award, presented by the Latin American Studies Association (LASA). He is the co-editor of American Crossings: Border Politics in the Western Hemisphere (Johns Hopkins University Press, 2015), Mexico's Security Failure: Collapse into Criminal Violence (Routledge, 2012), and El mundo desde México: Ensayos de política internacional (El Colegio de Mexico, 2008).

Before joining the NDU faculty in 2023, Sotomayor was Associate Professor of International Affairs and Director of the Security Policy Studies MA Program in the Elliott School of International Affairs at George Washington University, from 2018 to 2023. He also served as Associate Professor of Political Science and Program Coordinator for Latin American Studies at the University of Texas at San Antonio (UTSA), from 2015 to 2018. Likewise, between 2009 and 2015, Sotomayor was Associate Professor in the Department of National Security Affairs at the Naval Postgraduate School in Monterey, California. Sotomayor began his academic career in Mexico City, when he was appointed Assistant Professor of International Relations at the Centro de Investigación y Docencia Económicas CIDE, in Mexico, between 2004 and 2007.

Sotomayor has also been a research fellow and program coordinator at multiple academic institutions, including Mexico Policy Research Fellow at the Woodrow Wilson Center for International Scholars, Post-doctoral Research Fellow at the Center for Inter-American Policy Research (CIPR) at Tulane University, and Academic Coordinator of the UTSA Mellon Humanities Pathways Program, which received generous funding from the Andrew Mellon Foundation. He currently serves as a Non-Resident Affiliate Faculty of the Cisneros Hispanic Leadership Institute at George Washington University.

His research agenda has been funded by multiple agencies and institutions, including the Ford Foundation, the Defense Threat Assessment Agency (DTRA) at the Department of Defense, the Minerva Research Initiative, the Fulbright-Garcia Robles scholarship program, and the Elliott School of International Affairs Dean’s Research Fund.

In 2014 Sotomayor was the recipient of the LCDR David L. Williams Outstanding Professor Award, presented by the Naval Postgraduate School. He was also the recipient of the 2003-2004 Academic Council on the United Nations System (ACUNS) Dissertation Award. In 2021, the Center for Strategic and International Studies (CSIS), in partnership with the Diversity in National Security Network, included Sotomayor in its top 50 US National Security and Foreign Affairs Leadership List for his commitment to diversity and inclusion efforts in security studies.

Sotomayor received his MA, MPhil, and PhD in political science from Columbia University and a BA in international relations from the Technological Autonomous Institute of Mexico (ITAM).