Game theory says these things are a bad idea.

Every time we have a gun massacre, two things will happen: The Onion will publish a “No way to prevent this” article and the gun control debate will flare. The anti-gun side will try to get agreement on common sense gun laws, whoever the Sarah-Huckabee-Sanders-of-the-week is will say it’s premature, and nothing will happen except the guaranteeing of more massacres.

I’m going to presume something about you here, and if I’m wrong, I apologize. I’m going to assume you want fewer gun massacres. If you don’t—say, if you’re the NRA, who get airtime and contributions whenever innocents get gunned down—you’re not going to like this much. But if you just want people to not be shot full of holes when they attend music festivals, this might help.

Game theory is often applied to gun control, usually on the anti-control side. I’ll start by going through this logic, which is called “Good Guy With A Gun.”

Here’s the logic: A Bad Guy wants to rob a Good Guy. The Bad Guy might be armed, and the Good Guy might be armed. As game theory is obsessed with the concept of payoffs, we need to look at the two sides’ payoffs separately.

Let’s look at the payoffs for the Good Guy. Bad news: They’re 100% negative. Obviously, the unarmed Good Guy is in trouble against an armed Bad Guy. But the armed Good Guy doesn’t have a positive payoff either. Because the Bad Guy knows the attack is coming, the Good Guy loses most of the time against an armed Bad Guy. Even winning won’t guarantee a positive outcome. The armed Good Guy has guaranteed a gun confrontation: he might get shot in a situation where he would otherwise lose only money.

Now let’s look at the Bad Guy’s payoffs. He always wants to be armed, because a Bad Guy Without A Gun is almost always beaten by a Good Guy With A Gun. Against an unarmed Good Guy, the Bad Guy With A Gun’s payoff is presumed to be greater than 0. (This is a weak argument, since jail exists to put robbers in cages. Bad Guys know this, which is why they don’t commit ten heists a day. But for now, let’s say crime against an unarmed victim does pay, at least a bit.)

The argument continues with the presumption that 0 is greater than the Bad Guy’s payoff against an armed Good Guy. In the latter case, he guarantees a gunfight in which he can be killed or maimed, so he has to think about it first. This last value presumption is the linchpin of the anti-gun control argument.

Which works great if we all have one-shot revolvers and rational goals in life. But the logic crumbles when the Bad Guy is intent on murder and doesn’t care about consequences. Then, the Bad Guy goes here and aims there:

That’s five football fields away.

64-year-old white male millionaire Stephen Paddock set up 23 firearms, among them an AR-15 and a Kalashnikov rifle supported by bump fire stocks, on the 32nd floor of the Mandalay Bay. He smashed out a window and fired upon the Route 91 Harvest Festival crowd that was 500 yards away across a busy street. The density of the 22,000 concertgoers meant he hit almost 600 people, killing 58, and then turned his gun around and added one more body to his count. He was dead when the SWAT team blew open his door.

This was a country music concert in Nevada, not Lilith Fair; if the genre’s demographics holds, many attendees owned guns. But they didn’t have them when Paddock opened fire. If they had, the body count would’ve been higher. No Good Guy With A Gun would’ve done anything to improve the result. A pistol is accurate to 25 yards; the only thing they could hit was each other. As country musician Caleb Keeter noted in his mind-changing declaration, any Good Guy who pulled out his gun would’ve been shot by police. The value proposition for the victims if they were armed was worse than if they weren’t. (Heaven forfend if the victims had AR-15s of their own, as I expect they would have killed dozens of innocents inside the Mandalay Bay.)

If you have two people with handguns, you have an okay possibility that the Good Guy With A Gun could win. But if you do any of these things to the gun:

The Good Guy‘s payoff vs. this Bad Guy nearly always is disaster, gun or no. There is only one thing you can do to the Bad Guy’s guns that will make him less likely to win, and that is remove them. If the Bad Guy can’t obtain the high-range, high-capacity, high-rate of fire multiplicity of guns, he can’t win.

How do we know? We learn that gun homicide rates are 25 times higher in the US than in other such countries. We learn that the US has 30% of the world’s mass shootings and only 5% of its people. We learn that nations and states with more guns have more gun deaths. We learn that Australia has had 0 mass shootings since it enacted gun control in 1996, the UK has had 1 since then, and the US has had 1,500 mass shootings since Sandy Hook.

And if we really want to learn, we learn that the only difference between us and the other nations is that we have half the world’s guns and they don’t. And since the day after a mass shooting is supposedly not an acceptable day to discuss gun control even though there’s a mass shooting every day in the US, we will likely never discuss it.

But we must. Because a Good Guy With A Gun doesn’t have a blessed chance. He’s just as likely to be massacred as the rest of us. He just doesn’t believe it. So he fights for the right to possess his assault weapon, which won’t protect him from the Bad Guy With A Really Good Gun and never will. Meanwhile, the Bad Guys keep getting more and more really good guns, and keep killing more of us at a time, because we’re fervently committed to letting them do so.

After all, as The Onion says, there’s no way to prevent this.

This is the fifth of a series of posts on politics and game theory. Earlier posts have covered impeachment, Russian collusion, white supremacy, and abortion. These essays are in my book Game Theory in the Age of Chaos, which you can order by clicking the link.