The United States Military is made up of 5 different branches: These are the US Army, US Navy, US Air Force, US Marine Corps, and the US Coast Guard All except the Coast Guard belong to the Department of Defense. The US Coast Guard answers to the Department of Homeland Security.
The US Army handles responsibilities as the primary land combat force. The US Army consists of approximately a million soldiers, divided into the Active Army, Army Reserve and Army National Guard. While all of these Army entities have federal missions, the National Guard also performs missions stateside. Army National Guard units are largely combat units, but with support based units as well. Army Reserve units are almost always combat support or combat service support.
US Marine Corps
While the US Marine Corps appears very similar to the Army, it has a bit over 200,000 marines in service. The USMC is charged with providing combined arms task forces around the world, providing a rapid response force which is small, but highly qualified and well equipped to handle any mission or situation.
The Marines have integrated task forces with ground and fixed wing aviation, providing extremely responsive air support. There are active and Reserve Marines as well.
The US Navy is charged with the majority of operations at sea, and has about a half a million sailors. The Navy currently has approximately 276 ships and 4,000 aircraft. The US Navy has a very rich tradition that it imparts on its service members.
Navy sailors fight pitched battles against the most powerful forces of the world, perform military operations around the globe, and provide safety and security on the seas and oceans everywhere. The Navy has active and reserve units and detachments.
US Air Force
The US Air Force is the youngest of our armed forces, and the six hundred thousand members would like to believe it is the most glamorous. With about 6,000 aircraft, and also like the Army, the Air Force is divided into an active force, an Air Force Reserve and an Air National Guard.
US Coast Guard
The smallest of our armed forces is the US Coast Guard. With only about fifty thousand servicemen, it is by far the smallest, but prides itself on being one of the busiest. As the only armed force that isn’t under the DoD, the Coasties are one of the lead forces in Homeland Security.
The Coast Guard has active and reserve units, and auxiliaries who provide assistance as needed. The Coast Guard performs diverse missions including search and rescue, police operations and inspections of cargo and ships.