Joint Chiefs of Staff in the context of "Chief of Staff of the United States Army"

The United States Army (U.S. Army) is the land service branch of the United States Armed Forces. It is designated as the Army of the United States in the United States Constitution. It operates under the authority, direction, and control of the United States secretary of defense. As a part of the United States Department of Defense, it is one of the six armed forces of the United States and one of the eight uniformed services of the United States. The Army is the most senior branch in order of precedence amongst the armed services. It has its roots in the Continental Army, formed on 14 June 1775 to fight against the British for independence during the American Revolutionary War (1775–1783). After the Revolutionary War, the Congress of the Confederation created the United States Army on 3 June 1784 to replace the disbanded Continental Army.

The U.S. Army is part of the Department of the Army, which is one of the three military departments of the Department of Defense. The U.S. Army is headed by a civilian senior appointed civil servant, the secretary of the Army (SECARMY), and by a chief military officer, the chief of staff of the Army (CSA) who is a member of the Joint Chiefs of Staff. It is the largest military branch, and in the fiscal year 2022, the projected end strength for the Regular Army (USA) was 480,893 soldiers; the Army National Guard (ARNG) had 336,129 soldiers and the U.S. Army Reserve (USAR) had 188,703 soldiers; the combined-component strength of the U.S. Army was 1,005,725 soldiers. The Army's mission is "to fight and win our Nation's wars, by providing prompt, sustained land dominance, across the full range of military operations and the spectrum of conflict, in support of combatant commanders". The branch participates in conflicts worldwide and is the major ground-based offensive and defensive force of the United States of America.‌

The United States Air Force (USAF) is the air service branch of the United States Armed Forces. It is a part of the United States Department of Defense and is one of the six armed forces and one of the eight uniformed services of the United States. Tracing its origins to 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established by transfer of personnel from the Army Air Forces with the enactment of the National Security Act of 1947. It is the second youngest branch of the United States Armed Forces and the fourth in order of precedence. The United States Air Force articulates its core missions as air supremacy, global integrated intelligence, surveillance and reconnaissance, rapid global mobility, global strike, and command and control.

The Department of the Air Force, which serves as the USAF's headquarters and executive department, is one of the three military departments of the Department of Defense. The Department of the Air Force is headed by the civilian secretary of the Air Force, who reports to the secretary of defense and is appointed by the president with Senate confirmation. The highest-ranking military officer in the Air Force is the chief of staff of the Air Force, who exercises supervision over Air Force units and serves as one of the Joint Chiefs of Staff. As directed by the secretary of defense and secretary of the Air Force, certain Air Force components are assigned to unified combatant commands. Combatant commanders are delegated operational authority of the forces assigned to them, while the secretary of the Air Force and the chief of staff of the Air Force retain administrative authority over their members.

The Department of the Army (DA) is one of the three military departments within the United States Department of Defense. The DA is the federal government agency within which the United States Army (U.S.) is organized. It is led by the secretary of the Army, a civilian official appointed by the president and confirmed by the Senate. The highest-ranking military officer in the department is the chief of staff of the Army, who is also a member of the Joint Chiefs of Staff. Other senior officials of the department are the under secretary of the Army (principal deputy to the secretary) and the vice chief of staff of the Army (principal deputy to the chief of staff.)

The DA is a successor to the Department of War which was originally formed in 1789 as an Executive Department of the United States. The Department of War was split by the National Security Act of 1947 into the Department of the Army and Department of the Air Force on September 18, 1947.

General Order No. 1 for the surrender of Japan was prepared by the United States Joint Chiefs of Staff and approved by President Harry Truman on August 17, 1945.

It was issued by General Douglas MacArthur to the representative of the Empire of Japan following the surrender of Japan, and then issued by Japanese Imperial General Headquarters to the forces of the Empire of Japan on 2 September 1945. It instructed Japanese forces to surrender to designated Allied commanders, reveal all current military deployments, and preserve military equipment for later disarmament. It also specified the occupation of Japan and Japanese-controlled areas by forces of the Allied Powers.

The chief of staff of the Air Force (acronym: CSAF, or AF/CC) 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 chief of staff of the Air Force is an administrative position based in the Pentagon. The chief of staff does not have operational command authority over Air Force forces. That is within the purview of the combatant commanders who report to the secretary of defense. The chief of staff exercises supervision of Air Force units and organizations as the designee of the secretary of the Air Force.

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.

The chief of space operations (CSO) is the service chief of the United States Space Force. The CSO is the principal military adviser to the secretary of the Air Force for Space Force operations and, as a member of the Joint Chiefs of Staff, a military adviser to the National Security Council, the secretary of defense, and the president. The CSO is a statutory office held by a Space Force general, who is typically the highest-ranking officer on active duty in the Space Force.

The CSO is an administrative position based in the Pentagon, and while they do not have operational command authority over Space Force forces, the chief of space operations does exercise supervision of Space Force units and organizations as the designee of the secretary of the Air Force.