(a) For the purpose of preparing selected students for commissioned service in the Army, Navy, Air Force, or Marine Corps, the Secretary of each military department, under regulations prescribed by the President, may establish and maintain a Senior Reserve Officers' Training Corps program, organized into one or more units, at any accredited civilian educational institution authorized to grant baccalaureate degrees, and at any school essentially military that does not confer baccalaureate degrees, upon the request of the authorities at that institution.

(b) No unit may be established or maintained at an institution unless—

(1) the senior commissioned officer of the armed force concerned who is assigned to the program at that institution is given the academic rank of professor;

(2) the institution fulfills the terms of its agreement with the Secretary of the military department concerned; and

(3) the institution adopts, as a part of its curriculum, a four-year course of military instruction or a two-year course of advanced training of military instruction, or both, which the Secretary of the military department concerned prescribes and conducts.

(c) At those institutions where a unit of the program is established membership of students in the program shall be elective or compulsory as provided by State law or the authorities of the institution concerned.

(d) The President shall cause to be established and maintained in each State at least one unit of the program if—

(1) a unit is requested by an educational institution in the State;

(2) such request is approved by the Governor of the State in which the institution requesting the unit is located; and

(3) the Secretary of the military department concerned determines that there will be not less than 40 students enrolled in such unit and that the provisions of this section are otherwise satisfied.