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 Navy (SECNAV) is a statutory officer and the head of the Department of the Navy, a military department within the United States Department of Defense.
The Joint Chiefs of Staff (JCS) is the body of the most senior uniformed leaders within the United States Department of Defense, which advises the president of the United States, the secretary of defense, the Homeland Security Council and the National Security Council on military matters. The composition of the Joint Chiefs of Staff is defined by statute and consists of a chairman (CJCS), a vice chairman (VJCS), the chiefs of the Army, Marine Corps, Navy, Air Force, Space Force, and the chief of the National Guard Bureau. Each of the individual service chiefs, outside their JCS obligations, works directly under the secretaries of their respective military departments, e.g. the secretary of the Army, the secretary of the Navy, and the secretary of the Air Force.
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 chairman of the Joint Chiefs of Staff (CJCS) is the presiding officer of the Joint Chiefs of Staff (JCS). The chairman is the highest-ranking and most senior military officer in the United States Armed Forces and the principal military advisor to the president, the National Security Council, the Homeland Security Council, and the secretary of defense. While the chairman of the Joint Chiefs of Staff outranks all other commissioned officers, the chairman is prohibited by law from having operational command authority over the armed forces; however, the chairman assists the president and the secretary of defense in exercising their command functions.
The vice chairman of the Joint Chiefs of Staff (VJCS) is, by U.S. law, the second highest-ranking military officer in the United States Armed Forces, ranking just below the chairman of the Joint Chiefs of Staff. The vice chairman outranks all respective heads of each service branch, with the exception of the chairman, but does not have operational command authority over their service branches. The vice chairman assists the chairman in exercising their duties. In the absence of the chairman, the vice chairman presides over the meetings of the Joint Chiefs of Staff and performs all other duties prescribed under 10 U.S.C. § 153 and may also perform other duties that the president, the chairman, or the secretary of defense prescribes.
The Goldwater–Nichols Department of Defense Reorganization Act of October 4, 1986 made the most sweeping changes to the United States Department of Defense since the department was established in the National Security Act of 1947 by reworking the command structure of the U.S. military. It increased the powers of the chairman of the Joint Chiefs of Staff and implemented some of the suggestions from the Packard Commission, commissioned by President Reagan in 1985. Among other changes, Goldwater–Nichols streamlined the military chain of command, which now runs from the president through the secretary of defense directly to combatant commanders, bypassing the service chiefs. The service chiefs were assigned to an advisory role to the president and the secretary of defense, and given the responsibility for training and equipping personnel for the unified combatant commands.
The chief of staff of the Air Force is the service chief of the United States Air Force. They are the principal military advisor to the secretary of the Air Force on matter pertaining to the Air Force. They are a member of the Joint Chiefs of Staff, and thereby a military adviser to the National Security Council, the secretary of defense, and the President. The chief of staff is typically the highest-ranking officer on active duty in the Air Force, unless the chairman and/or the vice chairman of the Joint Chiefs of Staff are Air Force officers.
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 Defense Science Board (DSB) is a committee of civilian experts appointed to advise the U.S. Department of Defense on scientific and technical matters. It was established in 1956 on the second Hoover Commission's recommendation.
A unified combatant command, also referred to as a combatant command (CCMD) or (COCOM), is a joint military command of the United States Department of Defense that is composed of units from two or more service branches of the United States Armed Forces, and conducts broad and continuing missions. There are currently 11 unified combatant commands, and each is established as the highest echelon of military commands, in order to provide effective command and control of all U.S. military forces, regardless of branch of service, during peace or during war time. Unified combatant commands are organized either on a geographical basis or on a functional basis, e.g., special operations, force projection, transport, and cybersecurity. Currently, seven combatant commands are designated as geographical, and four are designated as functional. Unified combatant commands are "joint" commands and have specific badges denoting their affiliation.
The Office of the Secretary of Defense (OSD) is a headquarters-level staff of the United States Department of Defense. It is the principal civilian staff element of the U.S. Secretary of Defense, and it assists the Secretary in carrying out authority, direction and control of the Department of Defense in the exercise of policy development, planning, resource management, fiscal, and program evaluation responsibilities. OSD is the Secretary of Defense's support staff for managing the Department of Defense, and it corresponds to what the Executive Office of the President of the U.S. is to the U.S. president for managing the whole of the Executive branch of the federal government.
In the United States military, a general is the most senior general-grade officer; it is the highest achievable commissioned officer rank that may be attained in the United States Armed Forces, with exception of the Navy and Coast Guard, which have the equivalent rank of admiral instead. The official and formal insignia of "general" is defined by its four stars.
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. The Department of Defense 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., the Department of Defense's stated mission is to provide "the military forces needed to deter war and ensure our nation's security".
The structure of the United States Air Force refers to the unit designators and organizational hierarchy of the United States Air Force, which starts at the most senior commands.
The United States Department of Defense (DoD) has a complex organizational structure. It includes the Army, Navy, the Marine Corps, Air Force, Space Force, the Unified combatant commands, U.S. elements of multinational commands, as well as non-combat agencies such as the Defense Intelligence Agency and the National Security Agency. The DoD's annual budget was roughly US$496.1 billion in 2015. This figure is the base amount and does not include the $64.3 billion spent on "War/Non-War Supplementals". Including those items brings the total to $560.6 billion for 2015.
The Assistant Secretary of the Navy (Research, Development and Acquisition) (abbreviated ASN (RDA)) is a civilian office of the United States Department of the Navy. The Assistant Secretary of the Navy (Research, Development and Acquisition) requires Senate confirmation, and engages in duties as directed by the United States Secretary of the Navy.
