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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#291

Post by falcor84 »

pyuser583 wrote: post #253
falcor84 wrote: post #160

Earlier quoted context omitted.

Well, yes (except that Civ isn't a board game). And no, it doesn't make it seem absurd to me. My argument is that Western strategic thought (with games being a codification thereof, rather than the source of) generally considers countries as mostly atomic actors that can be defeated - the history of European warfare being filled with "gentlemanly" surrenders followed up by peace treaties, with guerrilla warfare being…

Finland comes to mind.

As an example of an Eastern country? Well touché, I suppose you're historically correct, but what I had in my mind for this distinction is not the line in the middle of Europe (between the First World and Second World), but that between Europe and Asia. Sorry if I miscommunicated.

Re: Missile defense is NP-complete

#292

Post by grafmax »

jsw97 wrote: post #8

The author explains that this problem is actually adversarial, in the sense that the attacker gets to observe defenses and allocate warheads and decoys accordingly. Thinking of our current circumstances, this suggests another cost of war: our offensive capabilities, as well as our defensive capabilities become more observable. Our adversaries are studying our strengths and weaknesses in Iran, and they will have a muc…

"Our" adversaries, huh? There are more people in our country than pedophile billionaires, but it's this group starting the wars, murdering civilians, and producing generations of "adversaries".

Re: Missile defense is NP-complete

#293

Post by [deleted] »

dlisboa wrote: post #55
myrmidon wrote: post #29

Earlier quoted context omitted.

This is absolutely true, but there is a strong counterpoint: You also learn the limits of your own systems and how to operate them most effectively yourself (and better than adversaries can, too). Just to pick a recent example: Russian air defense in the early stages of the Ukraine war was dismal (more specifically: defense against big, slow drones like Bayraktar), despite having sufficient AA capability "on paper"--…

There is an assumption here that the value in improving defenses is the same as improving offensive weapons. That is not the case in the assymetry that drones provide and Russia is the first example. Russia has not been able to improve AA capabilities to the point where it's "safe", for any definition of the word, neither has Israel. Israel and Gulf states often tout over 90% interception rate yet it's really at the…

[deleted]

Re: Missile defense is NP-complete

#294

Post by david_pearce »

wat10000 wrote: post #217
pc86 wrote: post #174

Earlier quoted context omitted.

> If your million-dollar interceptor protects a multi-million-dollar building from a $100 missile, and then that building is hit by a second $100 missile, was it worth it? I mean the assumption is that if the first missile hit the building, the second missile would have been fired at something else, right? Still seems worth it at face value especially if there's enough time between the two missiles that there aren't…

My assumption would be that the attacker builds missiles based on the defenses they want to defeat. If you have no defenses, maybe the defender builds 1,000 missiles. If you have 1,000 interceptors with 100% accuracy, then maybe the defender builds 2,000 missiles. This is why the superpowers mostly scrapped their ICBM defenses in the 70s. The technology worked fine. It's totally doable with 1970s technology if you're…

>However, the British were able to maintain the ability to defeat that system and destroy Moscow with a single submarine, all on their own

What are you referring to here?

Re: Missile defense is NP-complete

#295

Post by Havoc »

mattmaroon wrote: post #256
Havoc wrote: post #254

There is also a big real world experience element that is hard to account for mathematically. There are stories of ukrainian operators expressing bewilderment and BCC countries sending 8x interceptors at millions a pop at a 20k shaheed. The world doesn't seem to have acclimatized to well...how the world works now. There is a very fundamental disconnect at play here and I fear it'll get us all into trouble

Well, it’s less about the value of the interceptor and more about the value of what the drones are heading for. If it’s a desalination plant that makes 20% of your freshwater, eight missiles are probably well worth it because a lot of people can die. Middle Eastern countries have much more condensed critical infrastructure and economic targets than we do. Iran has expected a war like this for decades and been continu…

That logic right there is why the US is going to lose. That math only works in isolation

The Ukrainians don’t think about today’s tradeoff but also about tomorrows. They learned that when when a three day special operation turned into four years.

You have to match your best defenses against the best expected incoming attack- across time- even if it means taking a hit. Yes desalination plant included

The us doctrine of defend all the things all the time against everything has failed in light of modern drone warefare

Re: Missile defense is NP-complete

#296

Post by dotancohen »

EthanHeilman wrote: post #117
jsw97 wrote: post #8

The author explains that this problem is actually adversarial, in the sense that the attacker gets to observe defenses and allocate warheads and decoys accordingly. Thinking of our current circumstances, this suggests another cost of war: our offensive capabilities, as well as our defensive capabilities become more observable. Our adversaries are studying our strengths and weaknesses in Iran, and they will have a muc…

It doesn't have to be, defender reveals everything and attacker chooses best strategy. 1. The defender could use both electronic and physical decoys, use air and sea mobile platforms that are always in motion and are difficult to track. 2. The defender can fire at decoys, to convince the attacker the decoys work when they don't. 3. The defender could mix in cheap decoy interceptor missiles that miss so the attacker c…

Many historical wars have been won by deception.

Sun Tzu taught us: When you are weak, appear strong. When you are strong, appear weak.

Re: Missile defense is NP-complete

#298

Post by infinitewars »

dlisboa wrote: post #55
myrmidon wrote: post #29

Earlier quoted context omitted.

This is absolutely true, but there is a strong counterpoint: You also learn the limits of your own systems and how to operate them most effectively yourself (and better than adversaries can, too). Just to pick a recent example: Russian air defense in the early stages of the Ukraine war was dismal (more specifically: defense against big, slow drones like Bayraktar), despite having sufficient AA capability "on paper"--…

There is an assumption here that the value in improving defenses is the same as improving offensive weapons. That is not the case in the assymetry that drones provide and Russia is the first example. Russia has not been able to improve AA capabilities to the point where it's "safe", for any definition of the word, neither has Israel. Israel and Gulf states often tout over 90% interception rate yet it's really at the…

It doesn't have to work, when the military industrial complex benefits either way.

The U.S. is on a path to spending trillions of dollars to putting missile defense (and offense) systems in space with the Golden Dome.

Re: Missile defense is NP-complete

#299

Post by angelgonzales »

Havoc wrote: post #295
mattmaroon wrote: post #256

Earlier quoted context omitted.

Well, it’s less about the value of the interceptor and more about the value of what the drones are heading for. If it’s a desalination plant that makes 20% of your freshwater, eight missiles are probably well worth it because a lot of people can die. Middle Eastern countries have much more condensed critical infrastructure and economic targets than we do. Iran has expected a war like this for decades and been continu…

That logic right there is why the US is going to lose. That math only works in isolation The Ukrainians don’t think about today’s tradeoff but also about tomorrows. They learned that when when a three day special operation turned into four years. You have to match your best defenses against the best expected incoming attack- across time- even if it means taking a hit. Yes desalination plant included The us doctrine o…

The US already has “shoot the archer” doctrine which strategizes to target the site(s) launching cheap drones rather than the drones themselves. With US air superiority this seems feasible.

Re: Missile defense is NP-complete

#300

Post by teleforce »

varjag wrote: post #248
teleforce wrote: post #144

Earlier quoted context omitted.

Imagine the NATO reaction if on the very first day of Russo-Ukrainian war offensive is by Russia performing missiles bombing murdering 100 kids studying in Ukraine primary school. Trump candid reaction to the Iranian school incident when asked by reporter was "I can live with that".

We don't need to imagine. Hundreds of kids sheltered in Mariupol theater building were killed in one attack in the first weeks of the war.

Am I missing something?

The attack on the Iranian primary school (not makeshift sheltered building) is on the very first day of the war, not several weeks, months or years.

Not to downgrade the incident, but the Mariupol incident you mentioned probably happened in 2022 while the all out war started in 2014 [1],[2]. If you can refer and link to the particular incident it'll be helpful for verification.

[1] Siege of Mariupol:

https://en.wikipedia.org/wiki/Siege_of_Mariupol

[2] Russo-Ukrainian war:

https://en.wikipedia.org/wiki/Russo-Ukrainian_war

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