Mackenzie Eaglen is the Senior Policy Analyst for defense and homeland security issues at The Heritage Foundation.  

As an expert in Heritage's Davis Institute for International Studies, Eaglen's specialties include: the size and structure of U.S. military forces, military readiness and transformation, defense strategy and the defense industrial base. Her homeland security expertise focuses on issues involving budget and policy.

Before coming to Heritage in 2006, Eaglen was the principal defense adviser for Sen. Susan Collins (R-ME), a senior member of the U.S. Senate Armed Services Committee and the ranking member of the Senate Homeland Security Committee. Eaglen also spent more than two years as a Presidential Management Fellow at the Pentagon, where she did research and analysis on defense resources and budgeting, strategic planning, Iraqi reconstruction efforts, and the U.S. defense industrial base. In addition, she wrote speeches for Gen. Richard B. Myers, Chairman of the Joint Chiefs of Staff. 

Prior to her fellowship, Eaglen was a national security analyst at the Association of the United States Army's Institute of Land Warfare. She also once served as a legislative assistant for Rep. John E. Sweeney (R-NY).

Eaglen's op-ed articles have appeared in several publications, including in The New York Times, National Defense magazine and Army Times. Her paper, "A New Look at Readiness: Solving the Army's Quandary," is currently taught at the U.S. Army War College in Carlisle, Pa. She has served as a guest lecturer at American University, Georgetown University, University of Georgia, Indiana University and Hofstra University and participated in defense panels with the University of Pennsylvania, the U.S. Army War College, the National Guard Association and Security Industry Association. 

Eaglen received her master's degree in national security studies from Georgetown University in 2001. She graduated from Mercer University, in Macon, Ga., with a bachelor's degree in international affairs while serving in the Army Reserve Officer Training Corps.