Historically, control of the air has been a prerequisite to success for modern operations or campaigns because it prevents enemy air and missile threats from effectively interfering with operations of friendly air, land, maritime, space, and special operations forces, facilitating freedom of action and movement. Joint air operations are normally conducted using centralized control and decentralized execution to achieve effective control and foster initiative, responsiveness, and flexibility. When contemplating command and control (C2) options for joint air operations within the operational area, the joint force commander (JFC) can choose to exercise C2 through a functional component commander by designating a joint force air component commander (JFACC), one of the Service component commanders, or the joint force staff. Many factors will weigh on the JFC's selection-most notably the type and availability of forces and capabilities to accomplish the assigned mission.