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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#231

Post by don_esteban »

breppp wrote: post #199
iso1631 wrote: post #125

Earlier quoted context omitted.

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

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.

Re: Missile defense is NP-complete

#232

Post by jsw97 »

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"--…

Definitely, you have to weigh the benefit of experience against the cost of revelation. (And all the other costs of course.)

Re: Missile defense is NP-complete

#233

Post by don_esteban »

maratc wrote: post #79
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.

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…

Depends, blanketing Ben Gurion (or any airbase) with parked aircraft on the tarmac with carpet munition is a really bad day.

But yes, against protected targets cluster munitions do not achieve much.

If you have relatively few low-precision missiles, using single warheads means you are risking achieving NO damage (easier to intercept, a good chance that it will hit nothing), with a cluster munition you are guaranteeing at least some damage.

I think Iranians are mixing both types of warheads.

Re: Missile defense is NP-complete

#234

Post by don_esteban »

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.

Hm, Iran destroyed several of the radars used for seeing their missiles in the early stages of their trajectory.

Re: Missile defense is NP-complete

#236

Post by standardUser »

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.

Re: Missile defense is NP-complete

#237

Post by rdtsc »

Cpoll wrote: post #229
lumost wrote: post #226

Earlier quoted context omitted.

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…

> 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 the taxpayers to the arms manufacturers, but still if we go by the numbers...

Re: Missile defense is NP-complete

#238

Post by solatic »

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 missiles. Congratulations, you wrecked your economy, if you can even keep up production of interceptors for long enough. Lose.

The only winning moves are to either use ground troops to invade and dismantle your opponents' missiles to prevent that risk from being realized, or to play mutually-assured destruction games trying to convince the other side that you're just an insult away from doing it anyway. And a Western world that seems desperate to keep boots off the ground is not playing that winning move.

Re: Missile defense is NP-complete

#239

Post by aftbit »

inaros wrote: post #165

I spent some time reconstructing the current US missile defense interceptor numbers. This was done from open source DoD data, CSIS P-21 procurement exhibits, and CRS reports, that are are in depth, non partisan, objective policy analyses written by experts at the Congressional Research Service (CRS) specifically for U.S. Congress members. Also used Lockheed/RTX financial disclosures. The numbers are pretty bad… Way w…

How does this guarantee a political and strategic win for Iran?

Iran was already teetering on the edge of being a failed state: socially, economically, environmentally, and agriculturally. Iran is expending expensive ballistic missiles to force those THAAD and Arrow shoot-downs. Yes, they're winning the shot exchange ratio, but their economy is orders of magnitude smaller than the US. Besides, unlike the Gulf states, the US and Israel are not just sitting around playing defense. They are systematically destroying substantial fractions of the Iranian war machine and have both threatened and attacked domestic and international energy production, the lifeblood of the Iranian economy.

The only true winner of this war, however it shakes out in the end, is Russia. All of the Middle Eastern powers aligned with the US are going to be desperate to rebuild their interceptor stockpiles and will surely get priority over Ukraine, likely for a very long time as the production rates are very low as you've pointed out. Plus, Russian gas and oil are worth a lot more than they were prior to this war, and are being allowed to trade more openly as well.

Re: Missile defense is NP-complete

#240

Post by mikkupikku »

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…

The "if only one nuke gets through, you lose and the whole thing is pointless" is completely wrong. Even if surrender were mandatory after one nuke, all the other intercepted nukes would be thousands if not millions of lives saved.
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