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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#251

Post by pyuser583 »

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…

They are fake in the sense individual items are listed as having costs that are not accurate.

But really the defense deals are very complicated, and not based around buying x number of items.

You’re making a not well-formed query. How much is a shell?

Adam Smith pointed out the first pencil costs thousands of dollars, but the second is mostly free. Same dynamic here, but multipled by a thousand.

Re: Missile defense is NP-complete

#252

Post by ultimafan »

sgtsteaks wrote: post #97
jmyeet wrote: post #45

Pardon the pun but this is an arms race and the defenders are going to lose. There are broadly five classes of missiles (one isn't a missile per se): 1. Ballistic. These are traditional rockets, basically. While rockets are designed to reach orbit or leave the Earth, a ballistic missile basically goes straight up and comes down. The higher it goes, the further away it can get because of the ballistic trajectory and t…

You cannot shoot a drone down with a shotgun. The range on a shotgun is nothing. Do you know that it actually fires bb's out in a cone shape? If you aim a shotgun up in the air, you are not taking out any drones. Look up the video of the drone hitting the hotel in Bahrain to get an idea of the speed and altitude.

I think you and the previous comment are talking about different types of drones- the smaller commercial quadcopters used in the Russia-Ukraine conflict can be shot down with shotguns fairly effectively.

Both sides have been seen with one member of a squad carrying around an issued shotgun in an anti-drone role- the fact that it shoots pellets in a cone is precisely why it's so effective. Skeet shooting is a great example of how relatively small fast moving targets can be hit consistently at range with a shotgun and they are usually using much smaller/lighter pellets with poorer velocity/range, I would assume the loads used in an anti-drone role are bigger.

Re: Missile defense is NP-complete

#253

Post by pyuser583 »

falcor84 wrote: post #160
testaccount28 wrote: post #104

Earlier quoted context omitted.

to be clear: your claim is that the us military is misinformed because key constituents have played too many board games? does hearing it back like that make it seem absurd to you as well?

Well, yes (except that Civ isn't a board game). And no, it doesn't make it seem absurd to me. My argument is that Western strategic thought (with games being a codification thereof, rather than the source of) generally considers countries as mostly atomic actors that can be defeated - the history of European warfare being filled with "gentlemanly" surrenders followed up by peace treaties, with guerrilla warfare being…

Finland comes to mind.

Re: Missile defense is NP-complete

#254

Post by Havoc »

There is also a big real world experience element that is hard to account for mathematically.

There are stories of ukrainian operators expressing bewilderment and BCC countries sending 8x interceptors at millions a pop at a 20k shaheed. The world doesn't seem to have acclimatized to well...how the world works now.

There is a very fundamental disconnect at play here and I fear it'll get us all into trouble

Re: Missile defense is NP-complete

#255

Post by don_esteban »

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.

There is a huge difference between 'deterrence' in the sense of deterring a country from taking aggressive action it might have otherwise considered, and 'deterrence' in the sense you are using here (surrender without fight, we are so much stronger than you).

Re: Missile defense is NP-complete

#256

Post by mattmaroon »

Havoc wrote: post #254

There is also a big real world experience element that is hard to account for mathematically. There are stories of ukrainian operators expressing bewilderment and BCC countries sending 8x interceptors at millions a pop at a 20k shaheed. The world doesn't seem to have acclimatized to well...how the world works now. There is a very fundamental disconnect at play here and I fear it'll get us all into trouble

Well, it’s less about the value of the interceptor and more about the value of what the drones are heading for. If it’s a desalination plant that makes 20% of your freshwater, eight missiles are probably well worth it because a lot of people can die.

Middle Eastern countries have much more condensed critical infrastructure and economic targets than we do.

Iran has expected a war like this for decades and been continuously preparing, most of the other nations they have not.

Re: Missile defense is NP-complete

#257

Post by rdtsc »

pyuser583 wrote: post #251
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…

They are fake in the sense individual items are listed as having costs that are not accurate. But really the defense deals are very complicated, and not based around buying x number of items. You’re making a not well-formed query. How much is a shell? Adam Smith pointed out the first pencil costs thousands of dollars, but the second is mostly free. Same dynamic here, but multipled by a thousand.

> Adam Smith pointed out the first pencil costs thousands of dollars, but the second is mostly free. Same dynamic here, but multipled by a thousand.

The shells are already made by the 10 and 100s of thousands, Shaheds are also not a research project, so either one is in amortized serial production now.

What I meant is that a $10k shell doesn't cost that much. Russians are making the equivalent artillery shells for an _order_ of magnitude less for around $1k. A lot of defense costs are just overinflated simply because they can be. The government is spending taxpayer money, it's not really coming from the politicians' pockets. If the kickbacks are just right, they may in fact flow back into the politicians pockets.

Re: Missile defense is NP-complete

#258

Post by don_esteban »

myrmidon wrote: post #29
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…

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 direction) to deter them from attacking). Once the ware breaks out, you want to improve your capabilities as fast as possible.

Re: Missile defense is NP-complete

#259

Post by chasd00 »

jmyeet wrote: post #45

Pardon the pun but this is an arms race and the defenders are going to lose. There are broadly five classes of missiles (one isn't a missile per se): 1. Ballistic. These are traditional rockets, basically. While rockets are designed to reach orbit or leave the Earth, a ballistic missile basically goes straight up and comes down. The higher it goes, the further away it can get because of the ballistic trajectory and t…

Maybe the winning strategy is always attack and never be the one defending. That’s unfortunate.
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