There is a great line in that opening scene from The Big Lebowski where the narrator, Sam Elliot, says of “The Dude”:

And even if he’s a lazy man, and the Dude was most certainly that. Quite possibly the laziest in Los Angeles County, which would place him high in the runnin’ for laziest worldwide.

If you replace “Dude” with Lawrence O’Donnell; lazy with stupid; and Los Angeles County with MSNBC, you have a fair approximation of what follows.

I only have a masters degree and some hours towards an MBA. For the life of me, I don’t know what this douche is talking about.

He starts out talking about the muzzle velocity of a Winchester .223 round. It is rated at 3300 fps. And he talks about its cyclic rate with a large capacity magazine. And how many rounds a semiautomatic pistol can fire in a minute (he says 15). All of this is used to prove that teachers should not be armed. He also seems to think the kids in that school were trying to outrun the bullets. I’d suspect they were trying to get away from danger, but then I’m not O’Donnell

This is what we, in the infantry, sometimes referred to as “Martian Logic.” It is just a collection of numbers or facts tossed together that produce a result — a result that has nothing to do with the facts or numbers. Let’s take the muzzle velocity. (BTW, I don’t know what weapon the school resource officers cowering behind their cars had, but it was probably, according to all available articles, the Glock-21 in .40). If the shooter is at one end of a 30m hallway and a teacher with a Glock .40–muzzle velocity of about 1400 fps–is at the other, the .223 travels the distance in 0.03 seconds. The .40 limps in at 0.07. The practical effect is that they arrive at the same time.

The whole idea behind armed teachers or staff is that you are serving as a deterrent to potential shooters. In federal facilities, there are “active shooter” briefings and drills and you discover that quite a bit is known about how these people operate once they begin shooting. Based on interviews with the shooters that have been taken alive, we know they want to rack up a body count. They don’t take time to force doors. They don’t chase people. They move about methodically shooting the closest targets. This is why crawling under your desk makes a great deal of sense. Odds are the shooter will not come into your workspace to look, he’ll move on to visible targets. The presence of staff who are armed brings down the chances that facility will be chosen.

Shooters usually don’t wear body armor. Checking the history of recent shooters, I didn’t find any reference to body armor…but I stand ready to be corrected on that. So the teacher not having body armor is not optimal but it doesn’t invalidate the concept. Neither person with body armor at close range negates the superior range and cyclic rate of the rifle. If more that one teacher is armed, the odds change dramatically against the shooter.

One shooter–and again, I haven’t found any examples of two or more shooters working in tandem other than Columbine–is focused on one thing: killing. If a teacher emerges from a bypassed room (remember, these guys don’t waste their time forcing doors because most of them know they have only a short time before the cops arrive) and engages the shooter, win or lose, that means that the shooter stops killing, he has to take cover and defend himself, and more people survive.

Now if, you think as O’Donnell does, that all is lost because you can’t outrun a bullet, well, yeah, you’re dead. But the object isn’t to outrun. The object is to deter. The object is to harden the target so that once the shooter is past the lockable exterior door that he is not able to kill at will.

Teachers and staff who are competent in the use of firearms make a lot of sense. Even if it was Trump pushing the idea.