United States Department of Defense - United States Department of the Army

The Department of the Army is one of the three service departments in the United States Department of Defense. It is headed by the Secretary of the Army, a civilian, who is responsible for the administrative (non-operational) affairs of the United States Army.

The department was formed in 1789 as the United States Department of War and was renamed the United States Department of the Army on September 18, 1947.

The highest ranking military officer in the department is the Chief of Staff of the Army. It fights on land.

United States Army

The United States Army is the largest, and by some standards oldest, established branch of the armed forces of the United States and is one of seven uniformed services. Like all armies, it has the primary responsibility for land-based military operations.

The modern Army had its roots in the Continental Army which was formed on June 14, 1775, before the establishment of the United States, to meet the demands of the American Revolutionary War. Congress created the United States Army on June 14, 1784 after the end of the war to replace the disbanded Continental Army. The Army considers itself to be descended from the Continental Army, and thus dates its inception from the origins of that force.

Control and operation of the Army is administered by the Department of the Army, one of the three service departments of the Department of Defense. The civilian head is the Secretary of the Army and the highest ranking military officer in the department is the Chief of Staff. As of August 31, 2007, the Regular Army reported a strength of 519,471 soldiers. By the end of 2006, the Army National Guard (ARNG) reported 346,288 and the United States Army Reserve (USAR) reported 189,975, putting the approximate combined component strength total at 1,055,734.

Most U.S. Army units can be operationally divided into the following components from largest to smallest:
First United States Army insignia

* Corps: Formerly consisting of two or more divisions and organic support brigades, they are now termed an "operational unit of employment," that may command a flexible number of modular units. Usually commanded by a Lieutenant General. 20,000-45,000 soldiers.
* Division: Formerly consisted of three maneuver brigades, an artillery brigade, a division support command, an aviation brigade, an engineer brigade (in heavy divisions only) and other support assets. Until the Brigade Combat Team program was developed, the division was the smallest self-sufficient level of organization in the U.S. Army. Current divisions are "tactical units of employment," and may command a flexible number of modular units, but generally will include four brigade combat teams and a combat aviation brigade. Usually commanded by a Major General. 10,000-15,000 soldiers.
* Regiment: The Army, for the most part is no longer organized by Regiments. Rather, Battalions and Squadrons maintain Regimental Affiliations in that they are called (for example), 1st Battalion, 8th Infantry (Regiment is implied) and is written 1-8 Inf. In this case, there is no Regimental Commander and the Battlion is organizied as part of a Brigade for combat. The exceptions are those units, such as Armored Cavalry Regiments which remain organized, and fight, as a Regiment and have a Regimental Commander. The written designation is easy to distinguish and commonly misused. A "/" separates levels of command. 1st Squadron, 3rd Armored Cavaly Regiment is written 1/3 ACR where as the 1st Squadron, 6th Field Artillery (again, Regiment is implied) is written 1-6 FA.
* Brigade (or group): Composed of two or more battalions, and usually commanded by a Colonel, supported by a staff in a Headquarters and Headquarters Company. Since the Brigade Unit of Action program was initiated, maneuver brigades have transformed into brigade combat teams, generally consisting of two maneuver battalions, a cavalry squadron, a fires battalion, a special troops battalion (with engineers, signals, and military intelligence), and a support battalion. Stryker Brigade Combat Teams have a somewhat larger structure. 3,000-5,000 soldiers.
* Battalion (or Cavalry Squadron): Composed of two to five companies or batteries and led by a Battalion/Squadron Commander, usually a Lieutenant Colonel supported by a staff in a Headquarters and Headquarters Company/Battery. 300-1000 soldiers.
* Company (or artillery battery/cavalry troop): Designated A thru C (plus HQ or support companies/batteries/troops) when in a 3 company/battery battalion or A thru D when organized in a 4 company/battery battalion. Regimental Troops are designated A thru T, depending on the number of Troops. The Troops are then divided into their like Squadrons. Each company/battery/troop is composed of three to four platoons and led by a Company/Battery/Troop Commander, usually a Captain supported by a First Sergeant. 62-190 soldiers.
* Platoon: Composed of two or more squads and led by a Platoon Leader, usually a Second Lieutenant supported by a platoon sergeant (Sergeant First Class). 32 soldiers.
* Section: Usually directed by a Staff Sergeant who supplies guidance for junior NCO Squad leaders. Often used in conjunction with platoons at the company level.
* Squad: Composed of two teams and is typically led by a Staff Sergeant. 9-10 soldiers.
* Team: The smallest unit. A fireteam consists of a team leader (usually a Sergeant, but may be a Corporal), a rifleman, a grenadier, and an automatic rifleman. A sniper team consists of a sniper who takes the shot and a spotter who assists in targeting. 2-4 soldiers.

Army components

During The First World War, the "National Army" was organized to fight the conflict. It was demobilized at the end of World War I, and was replaced by the Regular Army, the Organized Reserve Corps, and the State Militias. In the 1920s and 1930s, the "career" soldiers were known as the "Regular Army" with the "Enlisted Reserve Corps" and "Officer Reserve Corps" augmented to fill vacancies when needed.

In 1941, the "Army of the United States" was founded to fight the Second World War. The Regular Army, Army of the United States, the National Guard, and Officer/Enlisted Reserve Corps (ORC and ERC) existed simultaneously. After World War II, the ORC and ERC were combined into the United States Army Reserve. The Army of the United States was re-established for the Korean War and Vietnam War and was demobilized upon the suspension of the Draft.

Currently, the Army is divided into the Regular Army, the Army Reserve, and the United States National Guard. Prior to 1903 members of the National Guard were considered state soldiers unless federalized by the President. Since the Militia Act of 1903 all National Guard soldiers have held dual status: as National Guardsmen under the authority of the governor of their state and as a reserve of the U.S. Army under the authority of the President. Since the adoption of the total force policy, in the aftermath of the Vietnam War, reserve component soldiers have taken a more active role in U.S. military operations. Reserve and Guard units took part in the Gulf War, peacekeeping in Kosovo, and the 2003 invasion of Iraq.

Various State Defense Forces also exist, sometimes known as State Militias, which are sponsored by individual state governments and serve as an auxiliary to the National Guard. Except in times of extreme national emergency, such as a mainland invasion of the United States, State Militias are operated independently from the U.S. Army and are seen as state government agencies rather than a component of the military.

Although the present-day Army exists as an all volunteer force, augmented by Reserve and National Guard forces, measures exist for emergency expansion in the event of a catastrophic occurrence, such as a large scale attack against the U.S. or the outbreak of a major global war.

The final stage of Army mobilization, known as "activation of the unorganized militia" would effectively place all able bodied males in the service of the U.S. Army. The last time an approximation of this occurred was during the American Civil War when the Confederate States of America activated the "Home Guard" in 1865, drafting all males, regardless of age or health, into the Confederate Army.