logoalt Hacker News

solatictoday at 8:44 PM5 repliesview on HN

The math and economics on missile defense are broken.

If your adversary uses nuclear-tipped missiles: within hours if not days, you are virtually guaranteed to suffer impact. Congratulations, New York is under a mushroom cloud. Lose.

If your adversary doesn't use nuclear-tipped missiles, you have a war of attrition whereby the cost of interceptors is greatly more expensive than the cost of building the conventional missiles. Congratulations, you wrecked your economy, if you can even keep up production of interceptors for long enough. Lose.

The only winning moves are to either use ground troops to invade and dismantle your opponents' missiles to prevent that risk from being realized, or to play mutually-assured destruction games trying to convince the other side that you're just an insult away from doing it anyway. And a Western world that seems desperate to keep boots off the ground is not playing that winning move.


Replies

aftbittoday at 8:59 PM

Shot exchange is a huge problem, made even worse by the arrival of cheap drones. But you're implicitly assuming that the adversary is on roughly equal economic footing. If your defense budget is $800 billion and your adversary's defense budget is $8 billion, you can afford to spend 100x as much shooting down their missiles as they spend lofting them.

There's also a danger in projecting linearly from the beginning of a war, where invading forces both tend to use more expensive stand-off munitions and also have to deal with more aggressive missile launches. As the defender's own air defense system gets degraded, the invader can switch from expensive long range stand-off munitions to cheaper stand-in munitions (like glide bombs) launched from much shorter range. Additionally, the invader will be able to diminish the defender's ability to launch missile strikes in the first place, either by destroying the launchers, the missiles themselves, or their production, thus reducing the demand on expensive high-capability interceptors.

Drones and mines continue to offer asymmetric warfare options that are very hard to counter without a robust low side on the high-low mix. Ukraine are the world's leading experts in this currently, and hopefully are involved with US and Gulf forces to try to improve this shot exchange ratio.

I am assuming nobody is using nukes though. That completely changes the picture. One must always assume "(some of) the missiles will get through". Traditional MAD does not require boots on the ground - merely the assurance that if Iran gets one nuke through and hits New York, the USA will respond with 100+ nukes. The real question then is what the other "large" nuclear powers (Russia and China, primarily) will do in response to that.

chasd00today at 9:04 PM

i don't think complete invulnerability was ever the goal of missile defense. It was meant to be a countermeasure to something where before there was none. I'm actually surprised it works as well as it does. Back when these things were first being developed and tested the thought was intercepting nuclear armed ICBMs, they were supposed to be massively destabilizing with respect to MAD and could conceivably give a nation first strike advantage. First strike advantage means just bare minimum survival not that you never get hit at all. Fortunately, that never really materialized.

mikkupikkutoday at 8:57 PM

The "if only one nuke gets through, you lose and the whole thing is pointless" is completely wrong. Even if surrender were mandatory after one nuke, all the other intercepted nukes would be thousands if not millions of lives saved.

show 1 reply
PowerElectronixtoday at 9:14 PM

Ground troops that can't advance due to a cheap nonstop drone and missile barrage is also not a solution as you are going to run out of troops before ypur enemy runs out of drones.

kurthrtoday at 9:00 PM

The losing move is using missile interceptors.

Whether it's high altitude drone swarms, terminally guided artillery munitions, hypersonic rail guns, or high energy laser defense, all are orders of magnitude cheaper than the interceptors and could be less than the cost of the (nuclear?) missile. It's true that generically defending against nukes is basically a fools errand, but if they're (also stupidly) limited to putting them on ICBMs with non-detonating fail safes, then it's probably economically doable and cheaper than the $10T forever war.

I'm sorry, the whole framing of this (OP) question/answer seems artificial and fundamentally silly.