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 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 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 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 National Guard Bureau is the federal agency responsible for the administration of the National Guard established by the United States Congress as a joint bureau of the Department of the Army and the Department of the Air Force. It was created by the Militia Act of 1903. The National Defense Authorization Act for Fiscal Year 2008, elevated the National Guard to a joint function of the Department of Defense. The 2007 NDAA, from the previous year, elevated the chief of the National Guard Bureau from a lieutenant general to a four-star general.
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 Judge Advocate General of the Navy (JAG) is the highest-ranking uniformed lawyer in the United States Department of the Navy. The Judge Advocate General is the principal advisor to the Secretary of the Navy and the Chief of Naval Operations on legal matters pertaining to the Navy. The Judge Advocate General also performs other duties prescribed to them under 10 U.S.C. § 5148 and those prescribed under the Uniform Code of Military Justice.
A rear admiral in the uniformed services of the United States is either of two different ranks of commissioned officers: one-star flag officers and two-star flag officers. By contrast, in most other countries, the term "rear admiral" refers only to an officer of two-star rank.
Vice admiral is a three-star commissioned officer rank in the United States Navy, the United States Coast Guard, the United States Public Health Service Commissioned Corps, and the National Oceanic and Atmospheric Administration Commissioned Officer Corps, with the pay grade of O-9. Vice admiral ranks above rear admiral and below admiral. Vice admiral is equivalent to the rank of lieutenant general in the other uniformed services.
The chief of the National Guard Bureau (CNGB) is the highest-ranking officer of the National Guard and the head of the National Guard Bureau. The position is a statutory office, held by a federally recognized commissioned officer who has served at least 10 years of federally recognized active duty in the National Guard; the Army National Guard or the Air National Guard. In a separate capacity as a member of the Joint Chiefs of Staff, the chief is a military adviser to the National Security Council, the Homeland Security Council, the secretary of defense, and the president on matters pertaining to the National Guard.
The Chief of the United States Army Reserve (CAR) is the commanding officer of the United States Army Reserve, the reserve component of the United States Army. As the highest-ranking officer in the United States Army Reserve, the CAR is the principal advisor to the chief of staff of the Army on all matters relating to the Army Reserve, and is responsible for the personnel, operations and construction budgets of the Army Reserve, subject to the supervision and control of the secretary of the Army. Dual-hatted as Commanding General, United States Army Reserve Command, the CAR is also responsible to the Commanding General, United States Army Forces Command for the oversight of operationally-deployed Army Reserve forces.
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.
