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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#161

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"--…

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 punches through the ceiling by virtue of sheer kinetic energy.

BTW I have no expertise in these matters, so corrections would be very welcome. I also recognize that I am commenting about something from the comfort and of being out of range and this discussion can be very distressing.

Re: Missile defense is NP-complete

#163

could use some investigation of the ukranians techniques -- the number of interceptors the U.S. used within the first four days of the war eclipsed the total amount Ukranians have had for the war

What the USA learned from Ukraine is that the Shaheds are amazing and they want them too [1], apparently.

[1] https://en.wikipedia.org/wiki/Low-cost_Uncrewed_Combat_Attac...

Re: Missile defense is NP-complete

#164

Earlier quoted context omitted.

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...

Lasers are not "all weather" weapons as far as I am aware. Clouds, snow, fog, rain, and just humidity all degrade their performance greatly.

The recently announced "Golden Dome" project intends to get around this issue by putting a vast constellation of satellites into orbit. Each satellite would likely need a serious source of power in order to use its laser. Assuming that's just an engineering problem, then the issue becomes coverage. That is, depending on the adversary's capabilities, you'd need an absolutely massive constellation in orbit [0].

[0] https://en.wikipedia.org/wiki/Golden_Dome_(missile_defense_s...

Re: Missile defense is NP-complete

#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 worse than the headlines suggest. But anyway nowadays, investigative journalism has been decimated....For example experts like Kelly Grieco at Stimson estimated that at 12 day war consumption rates, the entire US interceptor stockpile depletes in 4 to 5 weeks. We are now in week 4...

As of December 2025, CSIS documented delivery of 534 THAAD interceptors and 414 SM-3. The 12 day War burned through around 150 THAADs (that is 28% of inventory) and about 80 SM-3s. The current war has been drawing down from that already depleted starting point for 25 days straight...

Gulf states reportedly expended around 600 to 800 PAC-3 MSE interceptors in the first 72 hours of Epic Fury alone, and that is more than the entire global 2025 production ( about 620 units).

Meanwhile THAAD production is 96 per year….with a recent Lockheed commitment to quadruple to 400 per year, but that will only deliver these additional missiles after 2027 or later. For example the sole ammonium perchlorate supplier for every US solid rocket motor runs one plant in Utah, and the sole HMX/RDX source is a WWII facility in Tennessee…

The US has procured roughly 270 PAC-3 MSE ( the Patriots ) per year since 2015, but has diverted around 600 to Ukraine over four years. The exact remaining US stockpile is not known with the same precision as THAAD/SM-3, so they could not have more than 3000 before Epic Fury...

But it is known as I said above, Gulf allies burned through 600 to 800 or more PAC-3 MSE in the first 72 hours of Epic Fury alone from their own stocks. Since they have zero domestic production capacity, and will be competing with the US for the same Lockheed production line that only makes about 600 per year, Iran really has them by the balls.

By the way, the cost so far in munitions is 20 billion ( check references…).

Then on Intelligence...

Iran has 13 satellites of their own, and it is known to be receiving intelligence from the Russians. This data allows them to know exactly how many Patriots or THAAD were fired so far. They are also probably customers of MizarVision, a Chinese AI startup, that has been cataloguing every significant American military asset in the Middle East. Every base, every carrier strike group, every F-22 deployment, every THAAD battery, every Patriot missile position, tracked, labeled, analyzed, and posted publicly.

So...

Unless the US escalates to a Ground Invasion (most likely scenario…), or negotiates a deal with Iran, if Iran can keep their industrial production of missiles, or maybe move them far up and inside tunnels in its Northern Mountains, and...if the USA does not escalate to a ground invasion due to the political risks, they can actually win this war both from the political and strategic aspects, as incredible as that might seem.

Who is truly screwed are the Gulf countries, as their stocks of US missiles get progressively depleted… And they wont get a refill soon.

Russia strategic interests are in helping Iran, since it weakens the US and strengthens their hand in Ukraine.

What might make it worst for the Iranians is the Chinese view of this. I speculate they will prefer to help the US and its economy, by forcing the US to do a great commercial interesting deal for them, then using their strong leverage on Iran to come to an agreement.

Strategically, over the next four to six months: Russian wins, Iran wins (despite all the destruction), China wins, Israel loses, the US loses. Trump truly is the biggest loser...

"Are We Running Out of Missile Defense Interceptors?" - https://www.csis.org/events/are-we-running-out-missile-defen...

"‘Race of attrition’: US military’s finite interceptor stockpile is being tested" - https://www.defensenews.com/news/your-military/2026/03/06/ra...

"The Depleting Missile Defense Interceptor Inventory" - https://www.csis.org/analysis/depleting-missile-defense-inte...

"Over 5,000 Munitions Shot in the First 96 Hours" - https://www.fpri.org/article/2026/03/over-5000-munitions-sho...

"A Chinese AI Startup With 200 Employees Is Mapping Every US Military Asset in the Middle East — In Real Time" - https://breached.company/mizarvision-chinese-ai-satellite-us...

https://www.mizarvision.com/

Re: Missile defense is NP-complete

#166

Earlier quoted context omitted.

Lasers are not "all weather" weapons as far as I am aware. Clouds, snow, fog, rain, and just humidity all degrade their performance greatly.

The recently announced "Golden Dome" project intends to get around this issue by putting a vast constellation of satellites into orbit. Each satellite would likely need a serious source of power in order to use its laser. Assuming that's just an engineering problem, then the issue becomes coverage. That is, depending on the adversary's capabilities, you'd need an absolutely massive constellation in orbit [0]. [0] htt…

This is such an insane plan, and I don't mean that in a good way.

For one thing, it can do little to nothing about low flying nuclear tipped cruise missiles, especially in less than ideal weather. These already exist, so the Golden Dome system is already inadequate on day one.

Re: Missile defense is NP-complete

#167
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…

Russia is already shipping containers full of Iranian drones to the Ukrainian front. It doesn't take much imagination to see how geographic location is going to matter less and less as technology improves.

Re: Missile defense is NP-complete

#168
post #126
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.wik…

I seriously can't wait for this technology.

It can be purely defensive, and shoot down all aerial attacks - drones, etc. over your country's airspace.

So... no wild weasel, no successful air raids, etc. We're back to ground invasions, and frankly, a country can defend against those a lot easier.

And it also means countries not lobbing missiles at each other, and at oil fields and igniting them, or destroying shipping etc.

Re: Missile defense is NP-complete

#169

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…

> Well, yes (except that Civ isn't a board game).

It is actually several physical board games, the oldest of which is older than (and unrelated to) the computer game [0], as well as being a series of computer games that are basically digital board games.

[0] Well, except for the computer game based on it and its expansion, which, because of the other computer game, had the long-winded title "Avalon Hill's Advanced Civilization".

Re: Missile defense is NP-complete

#170

>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...

Try that on my spinning, mirror-coated missile!
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