(And no, arming more people wouldn’t have saved the victims in this massacre - imagine how many more deaths there would have been with multiple people shooting in a dark, crowded theater.)
Actually, had members of the audience been armed, there would have been far fewer casualties and killed, for purely logical, tactical reasons.
To start with, the gunman is intending to shoot many people, so his attention is distributed in many directions to those who *attract* his attention, such as those running away, those closest to him, whatever. He is shooting for “quantity”, not “quality”.
However, an armed citizen has only one target. The gunman. If you can imagine yourself in their shoes, this armed citizen is able to actually *aim* his weapon at the gunman. He can choose when to shoot, more or less, and what part of the gunman to shoot at.
In this case, the gunman was wearing body armor and a gas mask. Gas masks do not stop bullets, so that is where you aim. Even if the gunman’s body armor is not obvious, the citizen still has big advantages.
Say the gunman is hit twice on his body armor. He has no idea *where* the shots came from, and has a distracted second or two trying to figure out, while that aimed gun is still shooting at him.
The journalist figures, incorrectly, that an armed citizen would also be firing into a crowd. But there is *no* crowd around the gunman, because everybody is trying to get away from him.
Things like this start to add up in a hurry in the advantage of the armed citizen. Seconds are very long increments of time in a gunfight. Concealment in a crowd or situation is also an enormous advantage. And focus on a target really matters.
You are correct. And from what I have read even if you are wearing body armor, a hit from a large caliber round is quite noticeable, and would likely interrupt the shooter’s actions, and maybe even knock them off balance. A hit in any other place would likely stop the attack. Trained personnel keep fighting after they are wounded, lunatics and criminals usually don’t.