There shall be in the executive branch of the state government a military department. The Adjutant General shall be the executive head of the department and, as such, subordinate only to the Governor in matters pertaining thereto. There shall be in such department at least one (1) Assistant Adjutant General for Army, at least one (1) Assistant Adjutant General for Air, such other Assistant Adjutants General as may be authorized by rules and regulations of the National Guard Bureau of the United States of America, and such other officers, enlisted men and civilian employees as the Adjutant General shall, from time to time, determine.