The United States secretary of defense (SecDef) is the head of the United States Department of Defense, the executive department of the U.S. Armed Forces, and is a high-ranking member of the federal cabinet. The secretary of defense's position of command and authority over the military is second only to that of the president of the United States, who is the commander-in-chief. This position corresponds to what is generally known as a defense minister in many other countries. The secretary of defense is appointed by the president with the advice and consent of the Senate, and is by custom a member of the Cabinet and by law a member of the National Security Council.
The secretary of the Army is a senior civilian official within the United States Department of Defense, with statutory responsibility for all matters relating to the United States Army: manpower, personnel, reserve affairs, installations, environmental issues, weapons systems and equipment acquisition, communications and financial management.
The United States Department of the Army (DA) is one of the three military departments within the Department of Defense of the U.S. The Department of the Army is the federal government agency within which the United States Army (U.S.) is organized, and it is led by the secretary of the Army, who has statutory authority under 10 United States Code § 7013 to conduct its affairs and to prescribe regulations for its government, subject to the limits of the law, and the directions of the secretary of defense and the president.
The United States Department of the Air Force (DAF) is one of the three military departments within the Department of Defense of the United States of America. The Department of the Air Force was formed on September 18, 1947, per the National Security Act of 1947 and it is the military department within which the United States Air Force and the United States Space Force are organized.
The United States Department of Defense is an executive branch department of the federal government of the United States charged with coordinating and supervising all agencies and functions of the U.S. government directly related to national security and the United States Armed Forces. As of June 2022, the U.S. Department of Defense is the largest employer in the world, with over 1.34 million active-duty service members, including soldiers, marines, sailors, airmen, and guardians. DoD also maintains over 778,000 National Guard and reservists, and over 747,000 civilians bringing the total to over 2.87 million employees. Headquartered at the Pentagon in Arlington County, Virginia, just outside Washington, D.C., DoD's stated mission is to provide "the military forces needed to deter war and ensure our nation's security".
The Assistant Secretary of Defense for Health Affairs (ASD(HA)) is chartered under United States Department of Defense Directive (DoDD) 5136.1 in 1994. This DoDD states that the ASD(HA) is the principal advisor to the U.S. Secretary of Defense on all "DoD health policies, programs and activities." In addition to exercising oversight of all DoD health resources, ASD(HA) serves as director of the Tricare Management Activity.
The Assistant Secretary of the Air Force (SAF/AQ) is a civilian position in the Department of the Air Force that is appointed by the president of the United States and confirmed by the United States Senate. This position is established under Title 10 US Code Section 9016 and is one of five Assistant Secretary positions under the Secretary of the Air Force. The Assistant Secretary reports to the Secretary of the Air Force.
The under secretary of the Air Force, sometimes referred to as the under secretary of the Department of the Air Force, is the second-highest ranking civilian official in the Department of the Air Force of the United States of America, serving directly under the secretary of the Air Force. In the absence of the secretary, the under secretary exercises all the powers and duties of the secretary and serves as acting secretary when the position of secretary is vacant. The under secretary of the Air Force is appointed by the President, by and with the advice and consent of the Senate.
Bernard Daniel Rostker was Principal Deputy Assistant Secretary of the Navy from 1977 to 1979; Director of the United States Selective Service System from 1979 to 1981; Assistant Secretary of the Navy from 1994 to 1998; Under Secretary of the Army from 1998 to 2000; and Under Secretary of Defense for Personnel and Readiness in 2000–2001. From 1996 to 2001, he also served as Special Assistant to the Deputy Secretary of Defense for Gulf War Illnesses.
The Assistant Secretary of Defense for Indo-Pacific Security Affairs, or ASD (IPSA), is the principal advisor to the Under Secretary of Defense for Policy (USD(P)) and the Secretary of Defense on international security strategy and policy on issues of DoD interest that relate to the governments and defense establishments of the nations and international organizations within the Indo-Pacific region. It primarily includes the entire region from India to Japan, and the region where ASEAN is located. The position was originally titled Assistant Secretary of Defense for Asian and Pacific Security Affairs but was renamed by the Trump Administration alongside the renaming of the United States Indo-Pacific Command.
The Assistant Secretary of Defense for Sustainment (ASD(Sustainment)), formerly known as the Assistant Secretary of Defense for Logistics and Materiel Readiness (ASD(L&MR)), is one of three assistant secretaries reporting to the Under Secretary of Defense for Acquisition and Sustainment. Formerly the position was an adviser to the Under Secretary of Defense for Acquisition, Technology and Logistics, Deputy Secretary of Defense, and Secretary of Defense on logistics and materiel readiness issues within the Department of Defense (DoD), including programs related to logistics, materiel readiness, maintenance, strategic mobility, and sustainment support. As the principal logistics official within the senior management of the DoD, the ASD(Sustainment) exercises authority, direction and control over the director of the Defense Logistics Agency. Like all other Assistant Secretaries of Defense, the ASD(Sustainment) is considered a part of the Office of the Secretary of Defense.
The Assistant Secretary of Defense for Energy, Installations, and Environment, formerly known as the Deputy Under Secretary of Defense for Installations and Environment, provides management and oversight of military installations worldwide and manages environmental, safety, and occupational health programs for the Department of Defense (DoD). DoD's installations cover some 29,000,000 acres (120,000 km2), with 539,000 buildings and structures valued at more than $700 billion. The responsibilities of the ASD(EI&E) include the development of installation capabilities, programs, and budgets; installation-energy programs and policy; base realignment and closure; privatization of military housing and utilities; and integration of environmental needs into the weapons acquisition process. The ASD(EI&E) is also responsible for environmental management, safety and occupational health; environmental restoration at active and closing bases; conservation of natural and cultural resources; pollution prevention; environmental research and technology; fire protection; and explosives safety. The ASD(EI&E) reports to the Under Secretary of Defense for Acquisition and Sustainment, and is a part of the Office of the Secretary of Defense.
Heidi Shyu is an American engineer who has served as the Under Secretary of Defense for Research and Engineering in the Biden administration since July 25, 2021. She previously served as the United States Assistant Secretary of the Army for Acquisition, Logistics, and Technology ASA(ALT) from 2012 to January 30, 2016.
John Euler Whitley is an American government official who served as the acting United States Secretary of the Army from January 20, 2021, to May 28, 2021. He previously serviced as Assistant Secretary of the Army and acting director of cost assessment and program evaluation for the Department of Defense.
Christine Elizabeth Wormuth is an American defense official and career civil servant who serves as the United States Secretary of the Army since 2021. Wormuth previously served as the Under Secretary of Defense for Policy from 2014 to 2016.
Gabriel Omar Camarillo is an American attorney who has served as the 35th under secretary of the Army in the Biden administration since February 8, 2022. He previously served as Assistant Secretary of the Air Force from 2015 to 2017 during the Obama administration.
Alan F. Estevez is an American government official who is currently serving as under secretary of commerce for industry and security in the Biden administration.
Christopher Joseph Lowman is an American military official who is serving as the Assistant Secretary of Defense for Sustainment. He previously served as the acting Under Secretary of the Army from 2021 to 2022.
