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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#271

Post by YeGoblynQueenne »

breppp wrote: post #211
dlisboa wrote: post #197

Earlier quoted context omitted.

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.

I don't think we are arguing the same thing. I am arguing that even without any air defense, Iran would have difficulty hitting its targets in Israel with ballistic missiles due to low accuracy. When adding interception rates they have a real problem in attacking strategic facilities, air bases is a good example, which would be much more important than desalination plants. You can then see that they shifted to comple…

Shahed drones have a maximum range of 25000 km [bbc_1]. The distance from e.g. Isfahan to Tel-Aviv is ~1592 km [google]. Shaheds can reach Israrel from Iran.

As to them all being intercepted, in the 12-day war that seemed to be the plan, i.e. force Israel to waste interceptors on cheap drones [bbc_2]. That seems to have changed in the current conflict.

_______________

[bbc_1] With a maximum range of 2,500km it could fly from Tehran to Athens.

[bbc_2] When Iran attacked Israel with hundreds of drones in 2024, the UK was reported to have used RAF fighter jets to shoot some down with missiles that are estimated to cost around £200,000 each.

Both exceprts from:

https://www.bbc.co.uk/news/resources/idt-b3a272f0-3e10-4f95-...

[google] https://www.google.co.uk/maps/dir/Isfahan,+Isfahan+Province,...

Re: Missile defense is NP-complete

#272

Post by fpoling »

rdtsc wrote: post #237
Cpoll wrote: post #229

Earlier quoted context omitted.

> US makes ~50k artillery shells a month at a cost of about 10k per shell. 50000 * 10000 * 12 is 6B/year. I was surprised, but I suppose that passes the smell test for a ~1T/year defense budget.

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.

Re: Missile defense is NP-complete

#273

Post by gnabgib »

YeGoblynQueenne wrote: post #271
breppp wrote: post #211

Earlier quoted context omitted.

I don't think we are arguing the same thing. I am arguing that even without any air defense, Iran would have difficulty hitting its targets in Israel with ballistic missiles due to low accuracy. When adding interception rates they have a real problem in attacking strategic facilities, air bases is a good example, which would be much more important than desalination plants. You can then see that they shifted to comple…

Shahed drones have a maximum range of 25000 km [bbc_1]. The distance from e.g. Isfahan to Tel-Aviv is ~1592 km [google]. Shaheds can reach Israrel from Iran. As to them all being intercepted, in the 12-day war that seemed to be the plan, i.e. force Israel to waste interceptors on cheap drones [bbc_2]. That seems to have changed in the current conflict. _______________ [bbc_1] With a maximum range of 2,500km it could…

You need an edit on your first range (typo). 25Mm is amazing, nowhere is too far away (except the moon).

Re: Missile defense is NP-complete

#274

Post by fpoling »

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…

With Bayraktar it was a software update for radar that allowed for Russian to destroy them. The radar signature of Bayraktar was way off from a typical target that radars were looking for at the beginning of the war.

Re: Missile defense is NP-complete

#275

Post by elzbardico »

srean wrote: post #161
roysting wrote: post #100

Earlier quoted context omitted.

There is no amount of math that can make up for the lopsided dynamic of hypersonic missiles. The only reason the “iron/gold dome” con job was even plausible to plunder trillions in U.S. Monopoly money was because missiles were crude, slow, and not MIRVed or had decoys at one time. That was a long time ago though. MIT Prof. Emeritus, Theodore Postol, has been trying to warn about this basic, mathematically proved frau…

I agree that a barrage of maneuvering missiles can be neigh impossible to defend against. Regarding these cluster munitions though, other than very densely populated areas, do they inflict much damage ? Are they more powerful than a grenade, say ? It's going to devastating to soft tissue surely, and pierce through ordinary sheet metal, but normal concrete walls might offer sufficient protection. Unless, of course, it…

Technically those are ballistic missiles with Multiple Independent Re-Entry vehicles not cluster munitions.

Re: Missile defense is NP-complete

#276

Post by elzbardico »

simonsarris wrote: post #120
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…

On the other hand, the best way to improve your capabilities is to use them frequently. The Russian army assumed a state of readiness for the Ukraine invasion that turned out to be, well, less. Their special forces floundered, their logistics were (are still!?) unpalletized - using bespoke metal containers and wooden crates! Whereas the US military learned an awful lot from its (mis)adventures over the last decades.

I think Russia's strategy fault was more that they didn't expect the amount of support Ukraine could coalesce in such a short time.

Re: Missile defense is NP-complete

#277

Post by andrewflnr »

lumost wrote: post #226
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…

I don't see how drones don't make all conflicts into WW1. 100 Billion dollars buys about 3.3 million Shaheds assuming the manufacturing is not made more efficient. There are many questions on whether its possible to spend 100 billion dollars on Shaheds, or launch all of them. But this is more than enough to destroy any logistics and transportation infrastructure necessary for a ground invasion. There are many many co…

I think that what makes it not WWI is that not even trenches really save you from precision munitions.

Re: Missile defense is NP-complete

#278

Post by elzbardico »

swat535 wrote: post #218
deburo wrote: post #84

Earlier quoted context omitted.

That's not what deterrence means. From google: the action of discouraging an action or event through instilling doubt or fear of the consequences. It's meant to avoid conflict altogether, say with China and Taiwan.

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.

Re: Missile defense is NP-complete

#279

Post by fpoling »

don_esteban wrote: post #231
breppp wrote: post #199

Earlier quoted context omitted.

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

Iran does not have a million of them, the numbers they have are better utilized on targets in Gulf states. If Iran launched 10000 Shaheds towards Isreal, you can be sure quite a few would get by. Maybe Ukrainian drone interceptors can be made cheap enough to be good enough against massed Shaheds. We are still early in the new paradigm, there will be significant developments.

APKWS interceptor is about 35K USD and works much better than drone-based interceptors. The problem is to scale the production, training and deployment. Another problem is detection. One needs wast multilayered system that US military missed to build as big stationary radars are very hard to defend.

Re: Missile defense is NP-complete

#280

Post by elzbardico »

SegfaultSeagull wrote: post #20
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…

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

Iran can establish deterrence with asymetric means and let's not forget, that contrary to what most americans think, Iran is not a backward hell hole like Somalia or Afeganistan. For a third world country we could say they have a competent R&D infrastructure, with a good number of STEM graduates every year (with roughly half of them being woman, which shows they are casting a wide net for talents).

They also have a lot of leverage points in their geography, in the fact that the US is at a historical low point in its military capabilities.

US and Israel strategy seems to be to completely destruct Iran's economy, but the problem is that this is a game where they can also shoot back.

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