Our Staff & Fellows

In response to increasing demand for mentorship and increased interest in career pathways for climate and security practitioners, the Climate and Security Advisory Group (CSAG) has developed a community-wide Climate Security Fellowship Program. It is the first professional organization for emerging leaders seeking meaningful careers at the intersection of climate change and security. The program connects established climate security experts with pr... More

Chief Executive Officer

Expertise: U.S. Foreign Policy; U.S. Congress; International Trade; Business Diplomacy; Trans-Atlantic Relations; Sub-Saharan Africa; Diplomacy; Politics and Governance; International Law & War; Transitional Justice and International Criminal Law

Patrick C. Costello is the Chief Executive Officer of the American Security Project (ASP) in Washington, DC. Cos... More

Chief Operating Officer

Expertise:  Public diplomacy, military history, national security policy, nuclear security, U.S.-Russia relations, asymmetric operations

Matthew Wallin is ASP’s Chief Operating Officer, and has led ASP’s research on public diplomacy and strategic communications since 2011. As an expert in national security strategy and international relations, Matt... More

Senior Fellow for Climate Security

Expertise: Climate security, emergency Response/disaster preparedness, civil affairs, security cooperation, chemical, biological, radiological and nuclear (CBRN) issues, Homeland Security Exercise and Evaluation Program (HSEEP), interagency collaboration

Jessica Olcott Yllemo is a national security professional with 15 years of experience at the nexu... More

Climate Corps Fellow

Expertise: Politics and Governance; Climate Security; Sustainability; Environmental Justice; China

Thomas S. Benson is currently a Ph.D Candidate at the University of Delaware in Political Science and International Relations and is a Princeton Dissertation Scholar, Environmental Defense Fund Climate Corps Fellow, and Aspen Institute Future Climate Leader. ... More

Research and Programming Assistant

Expertise: Great Power Competition, Russian Foreign Policy, National Security and Space 

Tucker Hamilton graduated from The George Washington University with a B.A. in International Affairs with a concentration in security policy and a minor in Russian. His research interests include national security, grand strategy, Russian intelligence operations... More

U.S.-Russia Relations Intern

Expertise: U.S.-Russia relations; Latin American politics; Defense Policy; East Asian politics

Heberto Limas-Villers is an M.P.P candidate at the Harvard Kennedy School. His research interests include U.S. foreign policy, defense policy, and East Asia.

Heberto previous... More

Climate Security Intern

Expertise: Environmental Science, Policy Analysis, Climate Modeling, Renewable Energy, Environmental Policy

Sam Knoll is a senior at Boston University, currently completing an combined B.S and MA degree in Environmental Science and Energy Policy. His research interests include renewable energy, environmental policy, and food security.

Previously, Sam wor... More

U.S.-Russia Relations Intern

Expertise: U.S. Foreign Policy; U.S.-Russia Relations; State-Building, International and Domestic Economics; Political Thought; Comparative Governance

Vanessa Smith-Boyle is a senior at American University where she is earning a B.A. in International Studies with a minor in Economics. Her areas of focus include Europe and Eurasia, U.S. foreign policy and n... More

Climate Security Intern

Expertise: International Affairs and International Development, Environmental and Sustainability Science, Climate Security

Bailee Mathews is currently a junior at The George Washington University pursuing a B.A. in International Affairs with a concentration in International Development and a B.S. in Environmental and Sustainability Science with a minor in Econo... More

National Security Strategy Intern

Andrea Moreno is a graduating senior at UCLA earning her B.A. in political science. She is passionate about furthering her knowledge in government operations as well as pursuing careers related to international security. At UCLA, Andrea h... More