Major Sean M. Castilla is an Armor Officer currently serving in Headquarters, Department of the Army staff as part of the Joint Chiefs of Staff/Office of the Secretary of Defense Internship. Previous assignments include the 1st Cavalry Division, Special Operations Command Africa, and the 101st Airborne Division. He holds a M.P.M in Policy Management from Georgetown University, an M.A. in International Relations from St. Mary’s University, San Antonio, and a B.A. Psychology from the University of Texas, Austin.