The United States military defends the United States against all enemies and provides combat capabilities worldwide in support of United States security objectives.
While it's sometimes hard to tell (for example, the Army has aircraft and vessels while the Navy, Air Force, Marine Corps, and Coast Guard have ground forces), each branch has specific missions.
The Army serves the American people, protects the nation’s vital interests and fulfills its military responsibilities. The Army comprises the nation's largest and most extensive military ground capabilities. It provides the necessary forces and capabilities in support of national security and defense.
The Army's mission is codified by federal law:
- Preserve the peace and security and provide for the defense of the United States, the Commonwealths and possessions, and any areas occupied by the United States
- Support the national policies
- Implement the national objectives
- Overcome any nations responsible for aggressive acts that imperil the peace and security of the United States
Air Force mission
The mission statement of the U.S. Air Force is "fly, fight and win in air, space and cyberspace."
Like the other branches, the official mission of the USAF has been established by federal law.
Title 10, Section 8062 of the U.S. Code defines the mission of the USAF as follows:
- To preserve the peace and security and provide for the defense of the United States, the Territories, Commonwealths and possessions, and any areas occupied by the United States
- To support national policy
- To implement national objectives
- To overcome any nations responsible for aggressive acts that imperil the peace and security of the United States
The Space Force, a sub-branch of the Air Force, was created in December 2019. It is charged with developing guardians, acquiring military space systems, maturing military doctrine for space power and organizing space forces to present to combatant commands.
The mission of the U.S. Navy is to protect and defend the right of the United States and its allies to move freely on the oceans and to protect the country against its enemies.
Federal law defines the Navy’s mission as follows:
- To prepare the naval forces necessary for the effective prosecution of war
- To maintain naval aviation, including land-based naval aviation, air transport essential for naval operations, and all air weapons and air techniques involved in the operations and activities of the Navy.
- To develop aircraft, weapons, tactics, technique, organization and equipment of naval combat and service elements
Marine Corps Mission
The U.S. Marine Corps serves as the amphibious forces of the United States. Its mission is detailed in Title 10, Section 5063 of the U.S. Code (USC):
- The seizure or defense of advanced naval bases and other land operations to support naval campaigns
- The development of tactics, technique and equipment used by amphibious landing forces
- Such other duties as the president may direct
Coast Guard Mission
The Coast Guard is the only U.S. military branch not organized under the Defense Department. Instead, it falls under the Department of Homeland Security.
Title 10, Section 101(a)(4) of the U.S.C. says, "The term 'armed forces' means the Army, Navy, Air Force, Marine Corps and Coast Guard." Additionally, Title 14, Section 1 states, "The Coast Guard, as established 28 January 1915, shall be a military service and a branch of the armed forces of the United States at all times."
While the president can direct all, or part of, the Coast Guard under the service of the Navy during wartime, it is the only military branch that routinely engages in civilian law enforcement during peacetime. Title 14, Section 2 of the U.S.C. authorizes the Coast Guard to enforce federal law.
The Coast Guard statutory missions are divided into homeland security missions and non-homeland security missions. Non-homeland security missions are:
- Marine safety
- Search and rescue
- Aids to navigation
- Living marine resources (fisheries law enforcement)
- Marine environmental protection
- Ice operations
Homeland security missions are:
- Ports, waterways and coastal security (PWCS)
- Drug interdiction
- Migrant interdiction
- Defense readiness
- Other law enforcement
From Basic Training for Dummies, copyright © 2011 by Wiley Publishing, Inc., Hoboken, New Jersey. Used by arrangement with John Wiley & Sons Inc.
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