He called it, "taking control of the situation"
My buddy (a very well trained military man and defensive instructor) was at the range one day when a person said he thought he saw something downrange. My friend instinctively called "ceasefire."
Before I go on, one of the shooters on the line was a man shooting a Glock sideways with no safety protection. That man upon hearing the call for a ceasefire promptly turned toward my friend with the loaded handgun, pointed it and said "Man! you don't [explitive] tell me what the ____ to do!"
Before he spit all his words out my friends pistol out and he was yelling at the guy to put his pistol down, get on the ground, cross legs, fold your hands above your head or he will shoot.
Now I think its one thing to read a story on the internet and another to hear it from a friend. The story had me well, dumbfounded I guess. Take what you want from this story but here's what I got:
He either had two choices: calmly ask the man to point his firearm down range and take the chance of getting shot w/o defending himself or do exactly what he did. I debated with myself whether what he did was the right thing. I reasoned out later on he did do the right thing. Whatever choice, he was still at a risk for being shot. The logical choice was to draw his firearm.