Here is the definition of base from the DoD dictionary of military terms at http://www.dtic.mil/doctrine/jel/doddict/
base (DOD, NATO) 1. A locality from which operations are projected or supported. 2. An area or locality containing installations which provide logistic or other support. See also emergency fleet operating base; establishment. (DOD) 3. Home airfield or home carrier. See also base of operations; facility.
IMO, “base” is not a very appropriate term for the USMAWP. I think the cadets just use “base” a convenient term for “military installation” which is what the USMAWP unquestionably is.
here is the definition of military installation:
military installation (DOD) A base, camp, post, station, yard, center, or other activity under the jurisdiction of the Secretary of a Military Department or,in the case of an activity in a foreign country, under the operational control of the Secretary of a Military Department or the Secretary
of Defense. See also base; camp; station.
Semi-relevant trivia: not all USAF bases have airplanes or airfields.