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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#351

Post by myrmidon »

don_esteban wrote: post #258
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"--…

The defense against Bayraktar at the beginning (the big column to the north of Kiev) was dismal because AA assets were turned off, not because they were unable to shoot Bayraktars. The problem was command and coordination. Darwin worked and Russians learned (as did Ukrainians). Regarding your last point: In peace time, you want to prioritize hiding your true capabilities (perhaps inflating them in (misleading directi…

I'd argue that few things are more dangerous for a country than drastically overestimating your own military assets while trying to do big stick diplomacy-- that's how you end up completely lost (WW2 France), or throwing away hundred thousands of lifes for little gain (Russia now).

Sure, opponents thinking your "stick" is bigger in peacetime is nice, might save you some money and improve diplomatic outcomes, but those gains are marginal compared to overestimating yourself and then finding out the hard way...

Re: Missile defense is NP-complete

#352

Post by throwaway2037 »

hedora wrote: post #107
energy123 wrote: post #63

Earlier quoted context omitted.

The best missile defense is offsense: degrading the launchers, stockpiles and defense industrial base, with cheap stand-in munitions after SEAD, leveraging air and intelligence superiority. Expensive interceptors are only a stop-gap that buys you time for the offensive degradation. Expensive stand-off munitions, likewise, are a short-term stopgap until SEAD is complete.

Offense doesn't work at scale. As the cost of drones goes to zero, the expected damage you take is roughly proportional to how much you have to lose. This means larger / richer economies cannot win these sorts of wars. To see what I mean, check out this desalination plant map: https://www.theguardian.com/world/2026/mar/23/iran-threat-to... It doesn't help if your commander in chief is incompetent and your invasion st…

First, hat tip on that Guardian article that you shared. The map of desalination plants around the Persian Gulf is excellent.

My first thought looking at it: Why does Saudi Arabia have desal plants in Riyadh? It is 100s of km away from the Persian Gulf! Maybe they want some far away from the Gulf for security reasons? Else, it looks weird. I imagine that they need to pump sea (salty) water from the Gulf to Riyadh, desal it, then pump back the waste water. Quite a journey.

Re: Missile defense is NP-complete

#353

Post by throwaway2037 »

dlisboa wrote: post #146
energy123 wrote: post #121

Earlier quoted context omitted.

It's heavily dependent on geography. Iran is geographically "lucky" it's positioned near the Strait of Hormuz and near the oil facilities of multiple Gulf states, allowing it to exert extreme asymmetric pressure through a small amount of drones etc. Most states can't replicate that luck. Good luck to South Africa if they ever decide to wage a similar war. Strategic depth also largely nullifies the role of one-way att…

Israel is similiarly lucky that it is surrounded by neighbors with US bases that can intercept missiles and drones before they get to it. All of its more competent enemies are very far away. In a different scenario there'd be no motivation for a country like Iraq or Jordan to help. They can afford to try to destroy Iran's offensive capabilities because in-between countries allow their airspace to be used. Wars are us…

    > In a different scenario there'd be no motivation for a country like Iraq or Jordan to help.
While unprovable, I think the sentiment is too strong for Jordan. They have pretty good relations with Israel, and have been using their own fighter jets to down some drones from Iran. If anything, it is good practice for their airforce.

Re: Missile defense is NP-complete

#354

Post by shiroiuma »

teleforce wrote: post #302
pjc50 wrote: post #183

Earlier quoted context omitted.

There were significant civilian casualties right from the start of the war in Ukraine, and several massacred villages. Russian air defense shot down a civilian airliner mostly full of Dutch nationals and the response was just condemnation and tweaking the sanctions a bit.

My heartfelt sympathy to the MH17 victims and families, but the airplane was flying in the risky warzone. That does not discount the fact that it's an atrocious act by the Russian backed military. However, to send missile to primary school killing hundreds of school girls on the very first day of the war, if intentionally is just pure evil.

It wasn't intentional; the building was used by the military years before. The US had really badly out-of-date intelligence and was negligent in updating it. There's absolutely no military benefit to bombing a girl's school.

Remember Hanlon's Razor, and remember how incompetent the Trump Administration has been in everything ever since he took office.

Re: Missile defense is NP-complete

#355

Post by fakedang »

afdbcreid wrote: post #336
dlisboa wrote: post #55

Earlier quoted context omitted.

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…

There are two reasons this logic is incorrect. 1. It's not Iran's mercy, but deterrence. If Iran was to target critical infrastructure constantly, Israel and the U.S. would bomb its much more easily. Both sides currently avoid doing that for the same reason. 2. Targeting the same places again and again will mean they cannot target other places, like cities, where even a miss has greater impact. So the economy of muni…

Uh, Israel and USA are already bombing core infra in Iran. Iran is retaliating against Israel as your point 2 states, and against the Gulf countries on their critical monetary assets - because that's where it hurts either party. Targeting civilian infra in Israel means Israel's image of infallibility is shattered, while targeting monetary assets in Gulf countries (like gas fields, refineries, financial districts, etc) means that they're intent on applying pressure to the Gulf countries. They can't do the former to the latter because of the extremely large (90%+) expat populations, and they can't do the latter to the former because Israel's sensitive assets were presumably prepared for the long fight, so are likely to be heavily guarded.

Re: Missile defense is NP-complete

#356

Post by rcxdude »

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…

This is part of the logic behind strategic bombing, and there's a lot of writing on how it doesn't win wars and can sometimes be counterproductive: firstly it's harder to hit and damage infrastructure than you might think (especially once your target stars fortifying at all), secondly it can be easier and faster to repair critical infrastructure than you might think, thirdly it can easily get way more expensive than you might think, and lastly it doesn't demotivate people like you might think, in fact it tends to will people to fight harder, just because spite is such a motivating force.

Re: Missile defense is NP-complete

#358

Post by teleforce »

varjag wrote: post #342
teleforce wrote: post #300

Earlier quoted context omitted.

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 Ma…

While the Ruissan invasion was ongoing from 2014, the 2022 full scale invasion is different both in scope and volume. It is viewed as its own global event and has it own huge Wikipedia article. Iran had also been attacked by the USA (and Israel) previously. The theater was marked with huge inscription of "CHILDREN" on tarmac, in the pilots' native Russian. They killed them regardless. Either way do you think that if…

Yes on day one people barely know what's happening, life goes on as usual.

After several weeks of bombardment and siege like was happened in Mariupol, children were already stop attending schools, moved to other schools, go to bunkers, live in makeshift shelters or migrate to different cities [1].

"The Geneva Conventions state that the parties to a conflict must do their best to protect civilians, which may include moving civilians and civilian objects under their control if they are close to military objectives." [1]

[1] Fact check: What do we know about the airstrike on a school in Iran?

https://www.euronews.com/my-europe/2026/03/16/fact-check-wha...

Re: Missile defense is NP-complete

#359

Post by egorfine »

> developed [] algorithm that solves instances with 10,000 [] in under 7 minutes on a Macbook Pro [] The prior state-of-the-art timed out at 2 hours

Knowing how government IT procurement works, I'm afraid it's going to stay >2h for the foreseeable future even if the COTS solutions will bring this time down to a subsecond calculation.

Re: Missile defense is NP-complete

#360

Post by egorfine »

15155 wrote: post #324
Havoc wrote: post #295

Earlier quoted context omitted.

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…

Ukraine has no feasible means to actually act offensively, meanwhile, the United States is a nuclear weapons state. Pose a credible-enough threat and atomic deletion will ensue.

> meanwhile, the United States is a nuclear weapons state

This logic is outdated because it is pretty obvious that no one is going to employ nuclear warheads in a typical conventional war and thus the nuclear factor suddenly doesn't matter for war economics.

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