I've seen some news article comments excusing his inaction say he couldn't go up against a rifle with a handgun. On May 3, 2015 two AK 47 armed Muzzies showed up to crash Pam Geller's draw Mohammed party. If I heard correctly they were successfully interdicted by a man with only a handgun.
While an undercover FBI agent who knew the Muzzies were going to attack the party stood by and watched.
