Jeffrey LewisMissile Defense

My colleague, Philipp Bleek, uses writing prompts for exam questions. The other day on student, Karl Riedel, submitted an answer that amused Philipp so much he asked permission to share it with me. And I, in turn, asked permission to share it with you. Karl graciously agreed.

Prompt F) Explain ballistic missile defense, i.e. systems to intercept
ballistic missiles, to a relative who has no particular background in
this area.

“Karl, how does ballistic missile defense work?”

“Alright Mother. Imagine if you and Stacy, the neighbor who rear-ended you last week, sat on the edge of your property lines and stared angrily at each other all day. Now imagine both of you had a bucket of hand grenades that you could throw to blow up the other. These grenades are nuclear missiles, Mother.

“I see. Where are the police?”

“The neighborhood is in an anarchic state of nature, Mother. Now, the only thing that stops both of you from throwing a grenade at each other, is that because of the 4-second fuse, you would almost certainly get a grenade thrown back at you. You both know this, therefore you’re in a somewhat stable, yet suspicious and hateful, relationship.”

“I don’t see what this has to do wi-“

Now imagine, Mother, that one day you looked over and noticed a very expensive tennis racket made of solid gold in Stacy’s hand. The racket represents a ballistic missile defense system, and she intends to use this to swat your grenades away.”

“What? How? Is that even possible for a 62-year-old woman with Osteoporosis?”

“It’s not easy. She’d first have to identify that it is indeed a grenade leaving your hand, follow it in the air despite her well-known near-sightedness, not get distracted by birds that happen to fly by, and then hit it without dislocating something. But she does have options. She can throw it at your hand to make you drop the grenade, but this would require incredible reaction time and close proximity. She can wait until she sees the arc and throw it at the grenade mid-air. Or she can swat it away when its closer to her yard if she’s confident in her hand-eye coordination. Also, she could possibly do all of these, depending on how many tennis rackets she has and their variety.

“But that’s not fair. Also, I don’t think Stacy is that athletic.”

“That’s not the point, Mother. The point is that now she could hypothetically save herself from retaliation when she throws a grenade at you. The homeowners’ association is now very worried because the balance is upset and the likelihood of shrapnel hitting everyone’s lawn ornaments has now increased dramatically.

“So, what are my options?”

“Well, you can get a few golden rackets yourself, but they’re incredibly expensive compared to regular grenades and not always successful. You can stockpile many more grenades to overwhelm her defenses, or you can alter your grenades so that they have a high chance of avoiding her desperate flailing entirely.”

“Karl this is nonsensical, if I did any of those things wouldn’t we essentially be at square one?”

“Precisely, Mother. Except now neither of you can afford to remodel your homes and you’re both somehow even angrier at each other.”

“I see… So how would you broker disarmament with North Korea?”