generals; for the Air Force, the Chief of Staff and Vice Chief of Staff are generals; and for the Space Force, the Chief of Space Operations, and the Vice Chief of Space Operations are generals. In addition, for the National Guard, the Chief of the National Guard Bureau is a general under active duty in the Army or Air Force. There are several exceptions to these limits allowing more than allotted within the statute: An officer serving as Chairman or Vice Chairman of the Joint Chiefs of Staff; an officer serving as Chief of the National Guard Bureau counts only against their service's four-star cap; the commander of a Unified Combatant Command; the commander of United States Forces Korea; officers serving in certain intelligence positions i.e. the Director of the Central Intelligence Agency; officers serving in four-star slots added by the President to one service which are offset by removing an equivalent number from other services. Finally, all statutory limits may be waived at the President's discretion during time of war or national emergency. Appointment and tour length Four-star grades go hand-in-hand with the positions of office to which they are linked, so the rank is temporary; the active rank of general can only be held for so long- though upon retirement, if satisfactory service requirements are met, the general or admiral is normally allowed to hold that rank in retirement, rather than reverting to a lower position, as was formerly usually the case. Their active rank expires with the expiration of their term of office, which is usually set by statute. Generals are nominated for the appointment by the President from any eligible officers holding the rank of brigadier general or above who meet the requirements for the position, with the advice of the Secretary of Defense, service secretary (Secretary of the Army, Secretary of the Navy, or Secretary of the Air Force), and if applicable the Joint Chiefs of Staff. For some positions, statute allows the President to waive those requirements for a nominee deemed to serve national interests. The nominee must be confirmed by the United States Senate before the appointee can take office and assume the rank. General ranks may also be given by act of Congress but this is extremely rare. The standard tour for most general positions is three years, bundled as a two-year term plus a one-year extension, with the following exceptions: Service