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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#421

Post by andrewflnr »

fc417fc802 wrote: post #343
andrewflnr wrote: post #281

Earlier quoted context omitted.

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.

That assumes they want to escalate. So far at least their official statements have been clear about tit-for-tat. It could also backfire spectacularly. If a bunch of civilians suddenly get killed or other war crimes committed unilaterally by them (such as targeting energy infrastructure) their adversaries could gain political support for the current effort. Whereas gradually forcing all interceptors to be expended is…

The strategy of throwing ballistic missiles at all of their neighbors doesn't seem like one that's overly concerned with political support among their adversaries. And a fast bleed of interceptors works for them too, maybe better since it spends less time in this phase of the conflict. I don't buy it. The Iranians aren't stupid but I don't think they're playing 5d chess either.

Re: Missile defense is NP-complete

#422

Post by fc417fc802 »

andrewflnr wrote: post #421
fc417fc802 wrote: post #343

Earlier quoted context omitted.

That assumes they want to escalate. So far at least their official statements have been clear about tit-for-tat. It could also backfire spectacularly. If a bunch of civilians suddenly get killed or other war crimes committed unilaterally by them (such as targeting energy infrastructure) their adversaries could gain political support for the current effort. Whereas gradually forcing all interceptors to be expended is…

The strategy of throwing ballistic missiles at all of their neighbors doesn't seem like one that's overly concerned with political support among their adversaries. And a fast bleed of interceptors works for them too, maybe better since it spends less time in this phase of the conflict. I don't buy it. The Iranians aren't stupid but I don't think they're playing 5d chess either.

I agree that it's probably not 5D chess. But I have to contest that speed is to their advantage given such asymmetric military strength. A slow bleed prolongs the process while the world looks on and energy prices steadily rise. They certainly aren't endearing themselves with their neighbors but at the same time by only striking a minimum amount of infrastructure they avoid mobilizing the sentiment of the broader US or EU populations against them.

My impression is that an overly intense or otherwise disproportionate attack would risk inviting a significant increase in political support. Whereas so far it seems to be a wildly unpopular military campaign.

IMO the US botched this quite badly. I'm almost certain we could have found a way to go about disposing of someone who guns down protesters en masse and funds terrorism without inviting so much negative sentiment or economic volatility.

Re: Missile defense is NP-complete

#423

Post by andrewflnr »

fc417fc802 wrote: post #422
andrewflnr wrote: post #421

Earlier quoted context omitted.

The strategy of throwing ballistic missiles at all of their neighbors doesn't seem like one that's overly concerned with political support among their adversaries. And a fast bleed of interceptors works for them too, maybe better since it spends less time in this phase of the conflict. I don't buy it. The Iranians aren't stupid but I don't think they're playing 5d chess either.

I agree that it's probably not 5D chess. But I have to contest that speed is to their advantage given such asymmetric military strength. A slow bleed prolongs the process while the world looks on and energy prices steadily rise. They certainly aren't endearing themselves with their neighbors but at the same time by only striking a minimum amount of infrastructure they avoid mobilizing the sentiment of the broader US…

They're being selective about their targets, yes. That doesn't imply anything about the rate. They're not short on legitimate targets.

> IMO the US botched this quite badly.

Certainly.

> I'm almost certain we could have found a way to go about disposing of someone who guns down protesters en masse...

Honestly, I doubt it. I think the only time to do this that wouldn't have been a strategic disaster was at least ten years ago, probably more.

Re: Missile defense is NP-complete

#424

Post by don_esteban »

fpoling wrote: post #279
don_esteban wrote: post #231

Earlier quoted context omitted.

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.

Air-launched interceptors like this have the problem on relying on a super-expensive manned carrier (fighter or helicopter).

The intercept cost is now not only the cost of the interceptor, but also the cost of the flying hours of the launching platform, and the risk of losing the launching platform.

If you equip even some of your Shaheds with AA missiles (cheap manpads with autonomous IR target acquisition and guidance), like is already happening in Ukraine, the feasibility of APKWS becomes problematic. The technology is developing fast these days.

Re: Missile defense is NP-complete

#425

Post by dgroshev »

Not sure where the crucial SSPK number came from, given that the referenced link https://missilethreat.csis.org/system/gmd/ does not have neither the number nor data to calculate it. Even more importantly, using the test history too far back is incorrect, since the system was debugged and refined.

Also, a big omission in the post is NGI carrying multiple kill vehicles. Considering the relative cost of a launching system and a KKV, multiple KKVs flip the math quite significantly.

Re: Missile defense is NP-complete

#426

Post by dgroshev »

maxglute wrote: post #111

>Hence, for one warhead, a defender can launch 4 interceptors and have a 96% chance of successfully intercepting the incoming warhead. >Unfortunately, those numbers are optimistic. This part worth stressing, ceiling for more performant missiles, i.e. faster, terminal maneuvering, decoys are geometrically harder to intercept. Past mach ~10 terminal and functionally impossible because intercept kinematics will break in…

That goes both ways. Terminal manoeuvring gets difficult as speeds increase, too. Besides, higher tier threats are intercepted outside the atmosphere, where it would be prohibitively expensive (in mass and accuracy) for RVs to manoeuvre.

Your SSPK is way WAY too low. Also, the math on interceptions changes completely with multiple KKVs per interceptor (see NGI).

Decoys don't work even at the highest end (ICBMs), see Chevaline's history and its rapid decomissioning for an example of just that.

Re: Missile defense is NP-complete

#427

Post by myrmidon »

WalterBright wrote: post #417
myrmidon wrote: post #416

Earlier quoted context omitted.

A lot of people might find the idea fun, but actually sitting around in some remote base, just waiting for the next wave of drones to come? Even if you draft those people "for free", they could be working (or raise a family) instead, so the human cost is always there. In WW2, the US lost ~15000 airmen just in training accidents to crew the ~300k planes it built. I'm sure we could get that rate down substantially with…

The marginal cost of a fighter aircraft to shoot down a drone flying slow in a straight line would be minimal, especially compared with the expense of each guided counter-rocket. As for being targets themselves, the drones would be in enemy airspace so who/what is going to target the fighters?

I don't see how you realistically get airframe cost below $200k; you need basically a cropduster with a bunch of electronic equipment and weapon systems on top. That's worth 10 attack drones at least (realistically, US military would probably pay several times that).

> As for being targets themselves, the drones would be in enemy airspace so who/what is going to target the fighters?

Something like a sidewinder strapped under some of the attack drones. If you create the incentive (juicy, trained pilots exposed in slow aircraft engaging at low range) your opponent is gonna adapt. Exactly this evolution happened with Ukraine sea drones (already shot down several russian aircraft).

Re: Missile defense is NP-complete

#428

Post by falcor84 »

donkeybeer wrote: post #403
trick-or-treat wrote: post #344

Earlier quoted context omitted.

Wasting human lives in war is the goal of jihad. This is the part that westerners have a hard time understanding. Why does Hamas hold hostages in tunnels under their own civilian populations? Not because they think Israel will hesitate to bomb there, they know they won't. It's because the death of their own population is a goal in itself.

If wasting human lives in war is the goal of Jihad then America and Israel are the highest and most supreme jihadis in the world for several decades.

I believe that the argument was that jihad is about wasting the lives of their own citizens; America and Israel generally manage to reduce that.

Re: Missile defense is NP-complete

#429

Post by falcor84 »

donkeybeer wrote: post #400
falcor84 wrote: post #391

Earlier quoted context omitted.

> Logically for an Iranian the most rational response would be to always kill Americans or Israelis in this case. For what definition of rational? Do you believe their killing of Americans and Israelis has or will benefit Iranians?

What? What else is a military supposed to do to an invader's soldiers and agents in an active war? War means killing the enemies.

War is about achieving political ends, which killing may or may not be instrumental towards. It's very unclear to me whether Iran's killing of Americans and Israelis, either directly via missiles or via their proxies, had realized any benefits for the nation of Iran, let alone for the average Iranian.

Re: Missile defense is NP-complete

#430

Post by donkeybeer »

falcor84 wrote: post #429
donkeybeer wrote: post #400

Earlier quoted context omitted.

What? What else is a military supposed to do to an invader's soldiers and agents in an active war? War means killing the enemies.

War is about achieving political ends, which killing may or may not be instrumental towards. It's very unclear to me whether Iran's killing of Americans and Israelis, either directly via missiles or via their proxies, had realized any benefits for the nation of Iran, let alone for the average Iranian.

American and Israeli soldiers are invading Iran currently. So just like standard procedure for any war, killing as many enemy combatants as possible is the point and beneficial for Iran as it aids toward repelling the invasion. America at least can be pressured to withdraw as the general populace is ambivalent about the war.
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