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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#311

Post by yosefk »

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…

What produces this Iranian "mercy" at a time when Iran is extensively bombed, if not a combination of defensive and offensive capabilities providing escalation dominance?

Re: Missile defense is NP-complete

#312

Post by stickfigure »

tmnvix wrote: post #244
breppp wrote: post #212

Earlier quoted context omitted.

That's certainly what Iranian propaganda is saying, as if everybody is censoring their great successes. Fact is there is no meaningful reduction in Israeli attacks, while Iranian launching ability had greatly suffered. So these air bases are probably not being hit. Apart from it in the era of OSINT satellite imagery, it is no issue to publicize such damage, I don't know of any such imagery Regarding the gulf, there t…

I haven't seen imagery of damage to Israeli airbases, but plenty of imagery showing damage to US military bases. e.g. https://www.youtube.com/watch?v=o0cIOMVBSbU . Worth keeping in mind that in the case of Israel, censorship is very effective. From the Iranian perspective, the overall strategy seems to have been: 1. Deplete intercepter stock and probe US/Israeli defences using large amounts of older less accurate mis…

I suspect you're giving the Iranian response too much foresight and credit here. With the decapitation strike, it's unlikely that a coherent plan of "launch all the cheap stuff first" remained intact. The upside of decentralized control is that it's hard to shut down; the downside is that it's hard to do exactly this kind of coordination.

My guess (which seems to be borne out by the numbers, at least as gets reported) is that the bulk of the IRGC's missile capability has been launched already. Certainly not all, but it will continue to diminish over time rather than increase. Still, that doesn't mean the remaining stock isn't incredibly dangerous.

> My feeling is that this is going to get a lot worse for everyone involved.

There I agree.

Re: Missile defense is NP-complete

#313

Post by jandrewrogers »

wat10000 wrote: post #306
bluGill wrote: post #289

Earlier quoted context omitted.

That worked in 1970 because there were exactly two players who had incentive to not spend all the money so they agreed to reduce the total ICBMs instead. In the current world there are too many actors - it won't work, they can make thousands of missles. Ukraine has already proven you don't get to control when you are attacked. Thus the only option today is cost reduce defense and produce enough to intercept several t…

It doesn't matter if it's the only option if it's not possible to do it. Maybe it is possible. It does seem like it may be possible to defend against cheap drones with cheaper systems. Use lasers or good old-fashioned projectile guns instead of interceptor missiles. For defending against proper missiles, I don't see how it's possible with any near-future tech. Guns and lasers don't work. You have to use a missile and…

The US Navy is largely responsible for long-range ballistic missile defense, since you have to cross an ocean to hit the US. They also have among the most sophisticated missiles for that purpose, capable of killing an ICBM at apogee. The inventory of these missiles is much larger, every destroyer carries them, and recent variants are often considered the most competent of the various ABM platforms out there.

These cost ~$30M. They are in the process of scaling up production to a few hundred per year, with some help from the Japanese. Unit costs are coming down. These same missiles are also being deployed for land-based ballistic missile defense, despite their naval origin.

In the long-term you are seeing a convergence of the missile platforms as more capabilities are compressed into fewer missile designs. The US is pretty clearly evolving their systems to more of a “missile truck” architecture that is optimizing for the number of targets they can kill simultaneously at the maximum ranges that make engineering sense. Many aspects of new platforms like the B-21 all point in that direction.

A historical limitation is that the rocket motors used by most air defense missiles really weren’t adequate for ballistic missile intercept purposes. The US has invested a lot in closing that gap.

Re: Missile defense is NP-complete

#314

Post by solatic »

aftbit wrote: post #242
solatic wrote: post #238

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 m…

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…

Defense budget is an abstraction. At the end of the day, there are only so many factories with only so many raw inputs producing only so many interceptors per day. You cannot simply increase the defense budget in the event of a war of attrition and then attempt to outspend your enemy. And this is beside the political unpopularity of high defense budgets in peacetime, when they would need to be higher, to build the industrial capacity ahead of when it would be needed.

Re: Missile defense is NP-complete

#315

Post by solatic »

PowerElectronix wrote: post #249
solatic wrote: post #238

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 m…

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.

Ukraine is a poor example here because we've been poor allies to them. Drones are manufactured in factories that can be bombed, stockpiled in warehouses that can be bombed, transferred to the front lines in trucks that can be bombed. But Ukraine doesn't have the air force assets to achieve that. The Israelis do, and the amount of drones that have been launched at Israel has dropped considerably over the last three weeks.

Re: Missile defense is NP-complete

#316

Post by drak0n1c »

nerfbatplz wrote: post #75
SegfaultSeagull wrote: post #20

Earlier quoted context omitted.

Or perhaps they will learn they are outmatched, lack the resources and technological capabilities to compete, and deterrence will have been established.

The Iranians just hit an F35 with a proverbial box of scraps they put together in a cave. The Chinese military must have experienced collective euphoria when they saw that.

The "pen-testing" discoveries go both ways. In Iran, Chinese HQ-9B surface-to-air missile systems and YLC-8B anti-stealth radars failed to intercept any aircraft. In Venezuela, Chinese JY-27A early warning radars failed to detect approximately 150 incoming U.S. aircraft. In Pakistan, Chinese HQ-9B and HQ-16 systems failed to intercept Indian strikes.

Re: Missile defense is NP-complete

#317

Post by Maro »

srean wrote: post #24

Game theory would be useful for these kinds of modeling. Perhaps the government should have and advisory body that employs the smartest mathematicians for running these scenarios. Of course a lot of randomness needs to be modeled too. Wonder what would be a good name for such a body :) Paradoxically, if anyone leaks unpalatable information from the inside that would be a problem for the government. https://en.wikiped…

" .. the smartest mathematicians for running these scenarios .. "

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

> Claude Shannon called him "the smartest person I've ever met", a common opinion.

> Von Neumann founded the field of game theory as a mathematical discipline.

> .. leading him to a large number of military consultancies and consequently his involvement in the Manhattan Project.

> In 1950, von Neumann became a consultant to the Weapons Systems Evaluation Group..

> In 1955, von Neumann became a commissioner of the Atomic Energy Commission (AEC), which at the time was the highest official position available to scientists in the government.

> In his final years before his death from cancer, von Neumann headed the United States government's top-secret ICBM committee..

Re: Missile defense is NP-complete

#318

Post by dilyevsky »

owenmarshall wrote: post #109
hedora wrote: post #59

Earlier quoted context omitted.

Currently, we're using $1M interceptors to take out $30K drones. This asymmetry is here to stay. The end game probably involves At that point, it turns into a logistics problem that's much easier for the attacker than the defender. Iran's already demonstrated that one successful drone can do $100B-1T in damages, so a hit rate of 0.1% means a 1:100K cost:damage ratio.

This leans towards my belief that the US is fundamentally fighting last century's war against adversaries that have _massively_ evolved. Look at the Ukranians: they are currently fielding an entire suite of counter-drone tech: fast pursuit systems to hit Russian drones on launch, cheap FPV drones for last-mile intercept, integrated radar/acoustic monitoring to target and respond to launches... and of course, the Russ…

No one is using Patriots against Shaheds.

> fast pursuit systems to hit Russian drones on launch

They haven't done much of that at all...

> cheap FPV drones for last-mile intercept

Where do you think these particular drones are made? I'll give you a hint - it's pretty sunny here.

Re: Missile defense is NP-complete

#320

Post by 15155 »

pc86 wrote: post #175
maratc wrote: post #141

Earlier quoted context omitted.

In theory; in practice however, there's been rocket fire from Gaza towards Israel where the offence was literally a metallic tube with a bit of TNT at a cost of about $800 per rocket [0] while the defence was $100,000+ per interceptor [1]. This has been going on for years , and as far as I'm aware there was no depletion observed. [0] https://en.wikipedia.org/wiki/Qassam_rocket [1] https://en.wikipedia.org/wiki/Iron_D…

I don't know the economic numbers off the top of my head but I have to imagine it's hard to find Israelis who think they're spending too much money on rocket interceptors.

If Mexico as a nation state intentionally launched a single offensive rocket from Juarez to El Paso, we would just invade.

Interceptors are an unnecessary expense in the ways that they have been used in the past 15 years.

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