There shall be an adjutant general with rank not to exceed that of lieutenant general. The adjutant general shall be appointed by the governor and shall hold office for a term of four (4) years from the time of appointment and until his or her successor shall be appointed in his or her place and stead; provided, however, that this appointment may be revoked by the governor for cause or if the adjutant general shall have been found to be physically unfit for service, as provided by § 30-3-22. The first appointment under this section shall be made on the first Tuesday of January, 1967, or within ten (10) days thereafter, and subsequent appointments shall be made during the similar period in each fourth year thereafter. By virtue of his or her office, the adjutant general shall be the chief of staff to the governor and the commanding general of the Rhode Island army and air national guard; he or she shall be subordinate to only the governor in matters pertaining to the military and naval affairs of the state. The adjutant general shall perform such duties as may be required by chapters 1 — 14 and any other law of the state, and such other duties as pertain to the adjutant general under the regulations and customs of the United States Department of Defense and the laws of Rhode Island.