The Strategic Air Command (SAC) was both a Major Command

Major Command

Major Command or Major Commands are large formations of the United States Armed Forces. Historically, a MAJCOM is the highest level of command.There are two types of Major Commands in the United States military:...

 (MAJCOM) of the United States Air Force

United States Air Force

The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

 and a "specified command" of the United States Department of Defense

United States Department of Defense

The United States Department of Defense is the U.S...

. SAC was the operational establishment in charge of America's land-based strategic bomber

Bomber

A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...

 aircraft and land-based intercontinental ballistic missile

Intercontinental ballistic missile

An intercontinental ballistic missile is a ballistic missile with a long range typically designed for nuclear weapons delivery...

 (ICBM) strategic nuclear arsenal

Strategic nuclear weapon

A strategic nuclear weapon refers to a nuclear weapon which is designed to be used on targets as part of a strategic plan, such as nuclear missile bases, military command centers and heavily populated civilian areas such as large towns and cities....

 from 1946 to 1992. SAC also controlled the infrastructure necessary to support the strategic bomber and ICBM operations, such as aerial refueling tanker aircraft to refuel the bombers in flight, strategic reconnaissance aircraft, command post aircraft, and, until 1957, fighter

Fighter aircraft

A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

 escorts.

Following the fall of the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

, the Air Force instituted a comprehensive reorganization of its major commands.