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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#281

Post by andrewflnr »

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…

If Iran was having great success with their attacks, they wouldn't therefore tail off the intensity if they could help it. They would just start scoring more hits with the same, presumably maximum, rate of fire.

I think the obvious answer is the correct one here, that Iran's launch capacity has been degraded. That's not to say it will ever go to zero, so a lot of your other points still have some merit.

Re: Missile defense is NP-complete

#282

Post by rdtsc »

fpoling wrote: post #272
rdtsc wrote: post #237

Earlier quoted context omitted.

Now imagine for the same $10k cost making a cruise missile, instead. This is close to what a Shahed is -- the estimate is $20k-$50k / unit, so close enough. This is bonkers. Countries can now afford for the same cost * to make not a 10-20 mile range artillery shell, but a 1500 mile effective range cruise missile. * Defense costs are "fake" to a large degree. A lot of that is really corruption with money flowing from…

It is vastly more complicated to find targets at 1500 miles than at 20. So drones are effective at destroying big stationary civilian infrastructure and much less at long distance strikes at military targets. Russia's inability to destroy Ukrainian aviation is a good example. But then with solar and batteries civilian infrastructure becomes much more resilient against drone strikes.

> It is vastly more complicated to find targets at 1500 miles than at 20.

It's true but they are so cheap that launching a whole bunch and/or improving them incrementally is possible. Yeah they are for stationary targets mostly, for sure. And of course their sounds and relatively low speed does make them somewhat easier to shoot down with short range AA guns and can have automated acoustic early warning system (it's like a flying lawnmower or chainsaw).

Re: Missile defense is NP-complete

#283

Post by elzbardico »

pjc50 wrote: post #179
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.

In a direct conflict with China, the ICBM exchange would destroy the F35s on the ground.

There won't be a direct conflict with China, at least not in the last 10 years, because the US first needs to complete de-coupling his economy from China more, re-industralize in-shore or at least near-shore, and dramatically build up its military and logistic capabilities to fight an expeditionary campaign on China shores.

China also is not stupid, and no matter how much they posture, they won't invade Taiwan.

Re: Missile defense is NP-complete

#284

Post by elzbardico »

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.

A big part of the US involvment in the current war is driven by Christian Zionists, that literally believe that there needs to be a fucking end-of-the-times war in the region so Christ comes back.

Re: Missile defense is NP-complete

#285

Post by elzbardico »

standardUser wrote: post #236
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…

Take China for an example. No one knows China's true military capabilities, because they're rapidly evolving and because they virtually never use them. If there's an element of surprise to be had, they have it. But that cut's both ways, because China itself doesn't have experience exercising those capabilities. The learning curve could be noticeable. Meanwhile, no one doubts the ability of the US military to execute.

Basically the only country left in the world with expeditionary capabilities is the US.

It is hard to compare this with China. Different goals and philosophies.

Re: Missile defense is NP-complete

#286

Post by shdudns »

jonaslanglotz wrote: post #36
owenmarshall wrote: post #16

Two more sobering axes to introduce: cost and manufacturing capability. Numbers are hard to find for obvious security reasons, but using the numbers most optimistic to the defender[0] suggests an adversary using a Fatah type hypersonic is spending 1/3rd the cost of an Arrow interceptor, and is launching missiles that are produced at a much faster rate. Interception is deeply asymmetric in favor of the attacker. [0] h…

Calling a Fattah hypersonic is a misleading claim. It is simply a ballistic missile that reaches hypersonic speeds, which is different from a true hypersonic weapon in its flight path and ability to maneuver. This distinction is important because it makes it significantly easier to shoot down than something like a hypersonic glide vehicle or hypersonic cruise missile. But I agree with your point that it does remain d…

But they can steer, videos show that.

This really shouldn't surprise anyone. Iran graduates as many engineers as the US (70% women), but few of them are working on front-end A/B optimization of some boutique dating site.

And, having taken grad classes with folks graduated from Iranian universities, their training is excellent. The Persian kids were always at the top of their class.

EDIT: for the record the class I merely audited was graduate level (rational) mechanics - the class par excellence if you're going to build a hypersonic.

Some observations:

Half the class was Chinese, the academically better half was Persian.

I was the only Westerner (albeit also foreigner)

The girls were wearing veils.

According to the professor, the best mecanist (?) of the 20th century, Clifford Truesdelle, was an American

The Professor was Iranian.

Re: Missile defense is NP-complete

#287

Post by shdudns »

energy123 wrote: post #63
owenmarshall wrote: post #16

Two more sobering axes to introduce: cost and manufacturing capability. Numbers are hard to find for obvious security reasons, but using the numbers most optimistic to the defender[0] suggests an adversary using a Fatah type hypersonic is spending 1/3rd the cost of an Arrow interceptor, and is launching missiles that are produced at a much faster rate. Interception is deeply asymmetric in favor of the attacker. [0] h…

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.

So what Iran did in the Gulf

Cheap drones overwhelming defenses until the billion dollar radars and airfields got hit.

Then methodically hit everything according to a plan that forces allied forces to retreat to reliable water sources.

Whatever one thinks of Iran, the way they're waging this war is a masterclass in strategy.

Re: Missile defense is NP-complete

#288

Post by darepublic »

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…

Isn't Ukraine helping now with the anti missile/drone defense?

Re: Missile defense is NP-complete

#289

Post by bluGill »

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…

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 thousand per day.

Re: Missile defense is NP-complete

#290

Post by rendang »

elzbardico wrote: post #278
swat535 wrote: post #218

Earlier quoted context omitted.

Iranian here, you're assuming sanity. That doesn't work when your opponents pray for death and see martyrdom as victory. This is genuinely how Shia extremists think. They have nothing to lose and will sacrifice everything and everyone for their cause. They don't care about Iran or Iranians or prosperity of the nation.

Every country that has a opposition diaspora says the same stuff you're saying here. For what is worth, you could be from a family of Savak secret police members. And frankly that's not how it looks to me.

Every country's diaspora claims their country is ruled by Shia Muslims?
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