Mr. John D. Hill assumed his responsibilities performing the duties of the Assistant Secretary of Defense for Space Policy in August 2024. He previously fulfilled these duties from January 2021 until March 2022. He was appointed as the Deputy Assistant Secretary of Defense for Space and Missile Defense in January 2022. In these assignments he is responsible for overseeing formulation and implementation of defense policy and strategy for space security, nuclear deterrence, and missile defense and defeat posture; for countering weapons of mass destruction; and for related international relations of the Department of Defense (DoD).

A Presidential Rank Award recipient and member of the career Senior Executive Service, Mr. Hill has held a diverse range of assignments, including as DoD’s representative in negotiations on a Security and Defense Cooperation Agreement with Afghanistan, as Principal Director for Afghanistan, Pakistan, and Central Asia, and as Principal Director for East Asia.

In earlier assignments as the Director for Northeast Asia and as the Senior Country Director for Japan, Mr. Hill led DoD’s management of U.S. alliance relationships with Japan and the Republic of Korea and oversaw security policies regarding the Korean Peninsula.

Mr. Hill’s career includes extensive experience across a wide range of international negotiations encompassing space security, defense posture, status of forces, nuclear nonproliferation, defense industrial collaboration, international trade, and host nation support agreements. His early career highlights included roles in developing the longstanding U.S. policy on offsets in military exports and development and implementation of the Gulf War program under which coalition partners contributed $53 billion to defray U.S. costs.

As a member of the inaugural class of Mansfield Fellows, Mr. Hill served assignments on detail to the Japan Defense Agency, the Japan Federation of Economic Organizations (Keidanren), and Japan's Ministry of International Trade and Industry.

Mr. Hill joined DoD through selection to the Presidential Management Internship Program, serving assignments with the Army Security Assistance Command, the Office of Management and Budget, and the Office of the Secretary of Defense.

Mr. Hill received his Master of Arts in International Affairs from American University, and earned a Bachelor of Arts in Political Science at UCLA. He and his wife Lynn have three daughters, who are embarked on their own professional careers, and one grandson.