United States Department of the Army in the context of "United States Army"

The United States Department of Defense (DoD), also referred to as the Department of War (DoW), is an executive department of the U.S. federal government charged with coordinating and supervising the U.S. Armed Forces—the Army, Navy, Marines, Air Force, Space Force, and, for some purposes, the Coast Guard—and related functions and agencies. Headquartered at the Pentagon in Arlington County, Virginia, just outside Washington, D.C., the stated mission of the Department of Defense is "to provide the military forces needed to deter war and ensure our nation's security".

The Department of Defense is headed by the secretary of defense, a cabinet-level head who reports directly to the president of the United States. The president is commander-in-chief of the U.S. armed forces. Beneath the Department of Defense are three subordinate military departments: the Department of the Army, the Department of the Navy, and the Department of the Air Force. In addition, four national intelligence services are subordinate to the Department of Defense: the Defense Intelligence Agency, National Security Agency (NSA), National Geospatial-Intelligence Agency, and National Reconnaissance Office.

Arlington National Cemetery is the largest cemetery in the United States National Cemetery System, one of two maintained by the United States Army. More than 400,000 people are buried in its 639 acres (259 ha) in Arlington County, Virginia.

Arlington National Cemetery was established on 13 May 1864, during the American Civil War after Arlington Estate, the land on which the cemetery was built, was confiscated by the U.S. federal government from the private ownership of Confederate States Army general Robert E. Lee's family following a tax dispute over the property. The cemetery is managed by the U.S. Department of the Army. As of 2024, it conducts approximately 27 to 30 funerals each weekday and between six and eight services on Saturday, or 141 to 158 per week.

The National Security Act of 1947 (Pub.L. 80-253, 61 Stat. 495, enacted July 26, 1947) was a law enacting major restructuring of the United States government's military and intelligence agencies following World War II. The majority of the provisions of the act took effect on September 18, 1947, the day after the Senate confirmed James Forrestal as the first secretary of defense.

The act merged the Department of the Army (renamed from the Department of War), the Department of the Navy, and the newly established Department of the Air Force (DAF) into the National Military Establishment (NME). The act also created the position of the secretary of defense as the head of the NME. It established the United States Air Force under the DAF, which worked to separate the Army Air Forces into its own service. It also protected the Marine Corps as an independent service under the Department of the Navy. Aside from the unification of the three military departments, the act established the National Security Council and the Central Intelligence Agency, the latter of which is headed by the director of central intelligence.

The United States secretary of defense (SecDef), secondarily titled the secretary of war (SecWar), is the head of the United States Department of Defense (DoD), the executive department of the U.S. Armed Forces, and is a high-ranking member of the cabinet of the United States. 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 president appoints the secretary of defense 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.

Subject only to the orders of the president, the secretary of defense is in the chain of command and exercises command and control, for both operational and administrative purposes, over all DoD-administered service branches  – the Army, Marine Corps, Navy, Air Force, and Space Force – as well as the Coast Guard when its command and control is transferred to the Department of Defense. Only the secretary of defense (or the president or Congress) can authorize the transfer of operational control of forces between the three military departments (Department of the Army, the Navy, and the Air Force) and the eleven Unified Combatant Commands.

The chief of staff of the Army (CSA) is a statutory position in the United States Army held by a general officer. As the highest-ranking officer assigned to serve in the Department of the Army, the chief is the principal military advisor and a deputy to the secretary of the Army. In a separate capacity, the CSA is a member of the Joint Chiefs of Staff (10 U.S.C. § 151) and, thereby, a military advisor to the National Security Council, the secretary of defense, and the president of the United States. The CSA is typically the highest-ranking officer on active duty in the U.S. Army unless the chairman or the vice chairman of the Joint Chiefs of Staff are Army officers.

The chief of staff of the Army is an administrative position based in the Pentagon. While the CSA does not have operational command authority over Army forces proper (which is within the purview of the combatant commanders who report to the secretary of defense), the CSA does exercise supervision of army units and organizations as the designee of the secretary of the Army.

The secretary of the Army (SA or SECARMY) 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 secretary of the Army is nominated by the president of the United States and confirmed by the United States Senate. The secretary is a non-Cabinet-level official, subordinate to the secretary of defense. This position was created on September 18, 1947, replacing the secretary of war, when the Department of War was split into the Department of the Army and Department of the Air Force.

The United States under secretary of the Army is the second-highest-ranking civilian official of the United States Department of the Army, serving directly under the secretary of the Army. The secretary and under secretary, together with two military officers, the chief of staff and the vice chief of staff of the Army, constitute the senior leaders of the United States Army.

The following officials report to the under secretary of the Army:

The vice chief of staff of the Army (VCSA) is the principal deputy to the chief of staff of the Army, and is the second-highest-ranking officer on active duty in the Department of the Army.

The vice chief of staff generally handles the day-to-day administration of the Army Staff, freeing the chief of staff to attend to the interservice responsibilities of the Joint Chiefs of Staff. By statute, the vice chief of staff is appointed as a four-star general in the United States Army while so serving.