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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#191

Post by maratc »

dlisboa wrote: post #189
maratc wrote: post #184

Earlier quoted context omitted.

> that could be 100 billion USD in lost revenue that could be 100 billion USD in deferred revenue, if we assume that LNG is not going anywhere from wherever it's sitting underground, and will be simply extracted and sold later > plus whatever it costs to do the rebuild That is the real cost, which I would assume is nowhere near billions

> that could be 100 billion USD in deferred revenue, if we assume that LNG is not going anywhere from wherever it's sitting underground, and will be simply extracted and sold later That's not how revenue works at all.

I don't think anyone should have any concern whatsoever regarding Qatar revenues vs. Qatar budgets, as they are nowhere near bankruptcy, with this setback or without. Their position by projected GDP per capita may decrease from 6th (currently) to maybe 10th place in the world, which is still better than about 180 other countries.

Re: Missile defense is NP-complete

#192

Post by blueblisters »

Gaming this out for peer adversaries is mostly moot, right? The post-Cold War strategic balance has mostly hung on MAD. And Russia, in particular, has responded to any attempt at building missile shields with more capable missiles.

It's likely more relevant for asymmetric conflicts that involve conventional weapons, and would enable an otherwise less resourced adversary to become a near peer.

Dennis Bushnell from NASA presented this deck in 2001, and is quite prescient about UAVs and distributed warfare.

https://alachuacounty.us/Depts/epd/EPAC/Future%20Strategic%2...

Re: Missile defense is NP-complete

#193

Post by marcosdumay »

falcor84 wrote: post #80
gzread wrote: post #48

Earlier quoted context omitted.

More like the USA starting wars against countries, and those countries not immediately surrendering, to which the USA is shocked.

I think that there's a more general issue here with the US and the West in general having a mindset built up on playing Risk and Civ, which considers the foreign country as a whole as their opponent, whereas in practice, the adversaries are a multitude of individuals, for almost none of whom a surrender is the rational choice, especially (as sibling comments pointed out) when part of their reasoning and authority is…

> when part of their reasoning and authority is based on a divine mandate

If you are atheist is becomes rational to surrender to the people that are invading your house and killing your friends at random?

Re: Missile defense is NP-complete

#194

Post by breppp »

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…

> interception rate yet it's really at the mercy of Iran to not target their most vulnerable sites

And what this site and you don't account for, is Iranian rather low missile accuracy.

If Israel was at the mercy of Iranian attacks, Iran could have simply struck Israeli airbases to the point they cannot be used, and then stop any Israeli attacks on its territory.

It's pretty obvious they don't have the capabilities of doing that

Re: Missile defense is NP-complete

#195

Post by mrguyorama »

mamonster wrote: post #136
maratc wrote: post #79

Earlier quoted context omitted.

Cluster munitions are great against infantry in open field; less so against population centres equipped with advance warning systems. As it stands, they fail to even cause the damage worth offsetting by firing interceptors. The damage these inflict on Israel is not unsustainable, and they don't do much to create deterrence. Given a choice of conventional 500-800 kg warhead or cluster munitions warhead, I think that t…

>The damage these inflict on Israel is not unsustainable, and they don't do much to create deterrence. Has there been a study on this? What is the GDP loss of having however many Israelis go to bunkers due to incoming ballistics instead of working ? If a trash cluster missile that costs 100k USD to build causes 1mio USD worth of GDP to not be produced (numbers completely made up) then it's very worth it.

Ballistic missiles do not cost only 100k USD to build. They are very unlikely to ever be that cheap. Rocketry requires enough precision to not explode on the launcher. Ballistic missiles with conventional munitions are only useful for point targets. Cluster munitions like Iran uses are an admission that they aren't targeting specific systems, aren't expecting to penetrate defenses, or other reasons why they would waste a ballistic missile on the modern equivalent of the Paris Gun.

Harassment weapons don't do much. None of the harassment campaigns done by the Nazis for example really amounted to anything.

Modern Shaheds can be possibly built at a scale to affect that, but we really haven't seen it happen yet. That would be something like thousands launched in a single wave against a single city or installation. But they still lack the precision and warhead to be targeted meaningfully.

You need WW2 industrial scale manufacturing lines worth of Shaheds to get beyond harassment. You need to be producing hundreds a day or more. That kind of industry is nearly impossible to protect from your adversary so unlikely to take shape.

Re: Missile defense is NP-complete

#196

Post by mrguyorama »

wavefunction wrote: post #71
DivingForGold wrote: post #61

Earlier quoted context omitted.

Did I miss this ? Missing from the discussion is that Iran's cluster munitions in each single missle have absolutely overwhelmed Israels defense and would likely do the same to US military as well. Also to consider, Iran's $20,000 drones versus our $1 million dollar interceptors.

You could counter multipayload missiles by hitting the missile earlier in its trajectory before the payloads deploy, that was the plan for MIRV nukes but it requires usually forward interceptors or perhaps energy weapons we don't yet have.

Hitting Ballistic missiles "Midcourse" as you suggest requires interceptors that look more like https://en.wikipedia.org/wiki/Ground-Based_Interceptor or https://en.wikipedia.org/wiki/Arrow_3

It is.... Entirely infeasible to deploy these against tactical ballistics like Iran is using.

Re: Missile defense is NP-complete

#197

Post by dlisboa »

breppp wrote: post #194
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…

> interception rate yet it's really at the mercy of Iran to not target their most vulnerable sites And what this site and you don't account for, is Iranian rather low missile accuracy. If Israel was at the mercy of Iranian attacks, Iran could have simply struck Israeli airbases to the point they cannot be used, and then stop any Israeli attacks on its territory. It's pretty obvious they don't have the capabilities of…

You're making the same argument I am. If Iran had a small increase in accuracy they could hit targets that'd disable a lot of Israel military and civilian infrastructure. A lot of stuff is getting through. To counter that Israel has to achieve a perfect interception record. The balance is throughly on the side of offensive drone/missile warfare.

Re: Missile defense is NP-complete

#198

Post by breppp »

nerfbatplz wrote: post #112
9cb14c1ec0 wrote: post #102

Earlier quoted context omitted.

To be clear, that F35 was being incredibly careless, flying low in broad daylight. All the stealth features of an aircraft are useless if you can look at it with your own eyes. In any conflict with China, F35s would not be flown that way.

To be clear, Trump announced that the US had destroyed Iran's air defenses, missiles and missile launch capabilities. Trump also said that the US enjoyed air supremacy over Iran and were flying when and where they wished. Maybe one of these days we'll see a B-52 take off with JDAMs and not JASSMs but probably not, kind of scary to try and drop gravity bombs on a country that your stealth fighters can't fly over. http…

B-52s takeoff with stand-in weapons when attacking Iran, as their air defense is largely destroyed

https://theaviationist.com/2026/03/23/b-52s-launching-from-r...

Re: Missile defense is NP-complete

#199

Post by breppp »

iso1631 wrote: post #125
9cb14c1ec0 wrote: post #102

Earlier quoted context omitted.

To be clear, that F35 was being incredibly careless, flying low in broad daylight. All the stealth features of an aircraft are useless if you can look at it with your own eyes. In any conflict with China, F35s would not be flown that way.

You're holding it wrong? How many cheap-ass drones could you buy for the cost of one F35. 100k? A million?

None of these reached Israel from Iran this war, so maybe their superior quantity is not enough

Re: Missile defense is NP-complete

#200

Post by breppp »

baxtr wrote: post #68
varispeed wrote: post #49

Earlier quoted context omitted.

You miss the fact that many adversaries will not act rationally.

Especially when they're optimizing for afterlife.

The fact that many Iranian officials optimize stealing millions from the state, means they aren't optimizing for the afterlife
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