The National Guard armories and recruiting offices are normally manned by only a couple unarmed people; and most armories have weapons storage for pistols, rifles, grenade launchers, and light/medium machineguns--great targets for terrorists.
The NG here in San Diego has tanks and all kinds of heavily armored vehicles. Remember when that nut stole the tank frim the NG and drove all over town smashing up all sorts of stuff. It ended up a CHP officer had to shoot the guy.