Why RACES, the Radio Amateur Civil Emergency Service, is a government program defined in FCC Part 97 Subpart E (97.407). To transmit in RACES you must be enrolled in and certified by the responsible civil defense (emergency management) organization before the fact, and you operate under that agency's direction during a declared emergency.
Watch out ARES is the ARRL's Amateur Radio Emergency Service, an amateur-organized volunteer group that any licensee may join with no government certification. MARS is a Department of Defense auxiliary service with its own enlistment process, and SKYWARN is an NWS weather spotter training program.
RACES = Rules-based, Registered in advance with civil defense. ARES you just join; RACES you must be enrolled.