The United States Armed Forces are the military forces of the United States of America. Their core purpose is to protect the nation, defend its people and interests, uphold the United States Constitution, and support national policy at home and abroad. The Armed Forces are organized under the Department of Defense (DoD) and are led by the President of the United States as Commander-in-Chief, with civilian oversight exercised by the Secretary of Defense. Strategic military advice is provided by the Joint Chiefs of Staff. The DoD is headquartered at the Pentagon in Arlington, Virginia.
Mission and Legal Basis
The mission of the U.S. Armed Forces is established in federal law (commonly referenced in Title 10 of the U.S. Code).
In broad terms, the Armed Forces:
- Preserve peace and security;
- Support national policies and objectives;
- Deter aggression and, if necessary, defeat threats to the United States;
- Provide defense support of civil authorities and humanitarian assistance when directed.
- Beyond combat, the military frequently conducts disaster relief, humanitarian aid, evacuation operations, maritime safety and security (through the Coast Guard), and international cooperation exercises.
Branches
The United States maintains six distinct military branches, each with specialized roles. In peacetime, five branches fall under the Department of Defense and one (the Coast Guard) under the Department of Homeland Security, though the Coast Guard may operate as part of the Navy in wartime.
- United States Army
- The oldest and largest service (established 1775), focused on land dominance, ground combat, stabilization operations, and support to civil authorities.
- Main article: United States Army
- United States Navy
- A global maritime force providing sea control, power projection from the sea, strategic deterrence (ballistic missile submarines), and freedom of navigation.
- Main article: United States Navy
- United States Marine Corps
- A rapid-response, expeditionary force specializing in amphibious operations, crisis response, and combined-arms maneuver from the sea.
- Main article: United States Marine Corps
- United States Air Force
- Responsible for air superiority, global mobility, intelligence/surveillance/reconnaissance (ISR), and long-range strike.
- Main article: United States Air Force
- United States Space Force
- The newest branch (established 2019), responsible for space operations, including satellite communications, positioning/navigation/timing, missile warning, and protection of U.S. interests in space.
- Main article: United States Space Force
- United States Coast Guard
- A maritime security, safety, and stewardship service under the Department of Homeland Security in peacetime; conducts law enforcement, search and rescue, icebreaking, and environmental protection.
- Main article: United States Coast Guard
Command and Control
Civilian Control: The President (Commander‑in‑Chief) directs the Armed Forces, with policy and oversight from the Secretary of Defense.
Joint Chiefs of Staff: The Chairman, Vice Chairman, and the Service Chiefs advise on strategy, readiness, and joint operations.
Combatant Commands: Forces are organized for operations by geographic and functional Unified Combatant Commands (e.g., U.S. Central Command, U.S. Indo-Pacific Command; Special Operations, Strategic, Transportation, Cyber, Space). These commands integrate capabilities from multiple services.
Components: Active, Reserve, and National Guard
Each DoD service includes an Active Component and a Reserve Component. The National Guard (Army National Guard and Air National Guard) serves a dual state–federal role:
Active Duty: Full-time service members available for worldwide deployment.
Reserve: Part‑time forces who train regularly and can be mobilized for contingencies.
National Guard: Under state authority for domestic emergencies (e.g., disasters), but can be federalized for national missions.
Roles and Capabilities
Deterrence and Warfighting: Combined‑arms operations on land, at sea, in the air, in cyberspace, and in space.
Strategic Deterrence: Nuclear triad elements (ICBMs, ballistic missile submarines, and nuclear-capable bombers).
Homeland Defense & Civil Support: Air/missile defense, maritime security, disaster response, and defense support to civil authorities.
Humanitarian Assistance & Disaster Relief: Domestic and international relief operations and logistics support.
Alliances & Partnerships: Joint training and exercises with allies, support to collective defense arrangements, and security cooperation.
Personnel, Training, and Education
The force is composed of enlisted personnel, warrant officers, and commissioned officers. Training occurs at service academies (e.g., United States Military Academy), officer training schools (e.g., Officer Candidate School), and numerous technical and professional education institutions (e.g., National Defense University). Service members have access to education and transition programs such as the GI Bill and credentialing opportunities.
Bases and Global Presence
U.S. forces are stationed across the United States and at overseas locations to enable rapid response, sustain alliances, and deter aggression. Installations include major domestic bases, forward‑deployed fleets, expeditionary airfields, and prepositioned equipment sites.
Symbols, Values, and Traditions
Core Values:
Each branch maintains service‑specific values (e.g., Army—Loyalty, Duty, Respect, Selfless Service, Honor, Integrity, Personal Courage; Marine Corps—Semper Fidelis).
Insignia and Uniforms: Distinct ranks, branch insignia, occupational badges, and dress and utility uniforms.
Honors: Awards and decorations recognize valor, achievement, and service (e.g., Medal of Honor). Ceremonies and customs preserve history and esprit de corps.
Also See
National Guard • Army Reserve • Navy Reserve • Marine Forces Reserve • Air Force Reserve Command • Coast Guard Reserve
United States Army • United States Navy • United States Marine Corps • United States Air Force • United States Space Force • United States Coast Guard
External Links (Official)
Title 10, United States Code (uscode.house.gov)
U.S. Army • U.S. Navy • U.S. Marine Corps • U.S. Air Force • U.S. Space Force • U.S. Coast Guard