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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#121

Post by energy123 »

hedora wrote: post #107
energy123 wrote: post #63

Earlier quoted context omitted.

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.

Offense doesn't work at scale. As the cost of drones goes to zero, the expected damage you take is roughly proportional to how much you have to lose. This means larger / richer economies cannot win these sorts of wars. To see what I mean, check out this desalination plant map: https://www.theguardian.com/world/2026/mar/23/iran-threat-to... It doesn't help if your commander in chief is incompetent and your invasion st…

It's heavily dependent on geography. Iran is geographically "lucky" it's positioned near the Strait of Hormuz and near the oil facilities of multiple Gulf states, allowing it to exert extreme asymmetric pressure through a small amount of drones etc. Most states can't replicate that luck. Good luck to South Africa if they ever decide to wage a similar war. Strategic depth also largely nullifies the role of one-way attack drones in combat, but it doesn't nullify the role of fighters and bombers who can exploit that range. I'm not discounting drones, they're highly important in many geographies, as Ukraine is showing, but I don't buy into this conventional wisdom online that they're the pinnacle in every situation.

Re: Missile defense is NP-complete

#122

Post by pwndByDeath »

sumtechguy wrote: post #15
skywhopper wrote: post #10

Earlier quoted context omitted.

Have they, really? * Small rockets can now land themselves. Anything else?

Computer guidance? Better materials? Better telemetry?

Still short amount of time to make a decision based on very messy data

Re: Missile defense is NP-complete

#123

Post by keybored »

1234letshaveatw wrote: post #110
keybored wrote: post #95

Earlier quoted context omitted.

“Iranian kids may die... but that’s a prize I’m willing to pay.”

"I much prefer nuclear conflict"

Propose a nuclear free zone in the Middle East, propose a global nuclear free zone, propose to cooperate with other nuclear powers to disarm.

But that’s apparently not the real concern at all.

Re: Missile defense is NP-complete

#124

Post by Voultapher »

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…

Lasers. No really, near-future laser systems with adaptive optics and good spotting - for example distributed SAR satellites - dramatically shift that balance [0].

[0] https://toughsf.blogspot.com/2025/05/the-laser-revolution-pa...

Re: Missile defense is NP-complete

#125

Post by iso1631 »

9cb14c1ec0 wrote: post #102
nerfbatplz wrote: post #75

Earlier quoted context omitted.

The Iranians just hit an F35 with a proverbial box of scraps they put together in a cave. The Chinese military must have experienced collective euphoria when they saw that.

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.

You're holding it wrong?

How many cheap-ass drones could you buy for the cost of one F35. 100k? A million?

Re: Missile defense is NP-complete

#126

Post by hedora »

EGreg wrote: post #116

What happened to Iron Beam / lasers and those vaunted "space lasers" dubbed "star wars"?

Apparently, Iron Beam still exists (or at least was demoed in 2024).

Originally, the lasers were going to be mobile, but now they have to be stationary, so it will work like the game Missile Command, except you have unlimited ammo, but no concurrent shots, and the missiles can't be rotating (like a rifled bullet would).

That's much more feasible-sounding that I'd assumed (coming from low expectations).

https://en.wikipedia.org/wiki/Iron_Beam

Re: Missile defense is NP-complete

#127

Post by iso1631 »

varispeed wrote: post #49
SegfaultSeagull wrote: post #20

Earlier quoted context omitted.

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

You miss the fact that many adversaries will not act rationally.

Yes, if it was acting rationally the US Would not have spent billions trying to blow up an 80 year old man while massively increasing the price of oil and fertiliser globally leading to economic instability

But the US has not acted rationally. It hasn't since January 2021.

Re: Missile defense is NP-complete

#128

Post by jandrewrogers »

delichon wrote: post #4

Add multiple decoys and the missile math tends to become an argument for the importance of preemption. Han shot first for a good reason.

Decoys are greatly over-rated in ballistic missile systems. Sensors are so good at discriminating decoys from warheads that decoys are largely ineffective and have been for decades. This has borne out in Ukraine.

A decoy sufficiently sophisticated to look real to good sensors will have weight and characteristics that approach that of a real warhead, at which point you might as well add another warhead. Decoys only make sense if the marginal cost of adding them is low.

Re: Missile defense is NP-complete

#129

Post by iso1631 »

energy123 wrote: post #121
hedora wrote: post #107

Earlier quoted context omitted.

Offense doesn't work at scale. As the cost of drones goes to zero, the expected damage you take is roughly proportional to how much you have to lose. This means larger / richer economies cannot win these sorts of wars. To see what I mean, check out this desalination plant map: https://www.theguardian.com/world/2026/mar/23/iran-threat-to... It doesn't help if your commander in chief is incompetent and your invasion st…

It's heavily dependent on geography. Iran is geographically "lucky" it's positioned near the Strait of Hormuz and near the oil facilities of multiple Gulf states, allowing it to exert extreme asymmetric pressure through a small amount of drones etc. Most states can't replicate that luck. Good luck to South Africa if they ever decide to wage a similar war. Strategic depth also largely nullifies the role of one-way att…

It's America that's waging this war, having attacked Iran for no reason the world can see

It's somewhat similar to Russia waging a war in Ukraine, although I can see some reasons for Russia to attack Ukraine (mainly territory)

Re: Missile defense is NP-complete

#130

Post by OrangePilled »

quotemstr wrote: post #27

The sole mention of directed energy: > Directed energy has been proposed as a cost-effective alternative, but introduces its own scheduling constraints — dwell time, platform coverage, atmospheric degradation — with similar scaling issues The author is doing the thing where a writer tries to bamboozle the reader into a conclusion without having to prove it by overwhelming the reader with nouns. Life is too short for…

Bearing in mind the three constraints quoted, which of these do you think a country's deployed directed-energy weapons (e.g., US, Israel, Russia) would be useful against:

https://missilethreat.csis.org/country/iran/

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