I occasionally carry a firearm, but it's for protecting me or my family against an attacker. Honestly it's more for if I run across wild hogs than anything. It doesn't make me an action hero who can charge a mass shooter.

In the event of a mass shooting, the rule is to run. If you can't run, you hide. If you can't run or hide, you fight back.

Carrying a gun doesn't change that. My little pocket pistol is inaccurate, low-capacity, and low power. If I try to use it to fight a mass shooter I'm probably just gonna be putting more bullets in the air while getting myself killed.

Tackling the shooter like was done in the video is a better tactic. Even if you could draw and shoot accurately in the time it takes to run a few steps, the shooter would probably still have time to do damage before bleeding out. Tackling them and taking control of the gun is faster and more effective.