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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#391

Post by falcor84 »

donkeybeer wrote: post #361
falcor84 wrote: post #305

Earlier quoted context omitted.

Yes. Absolutely. If there are invaders who are killing everybody around me and telling me that they'll stop and generally let me be if I surrender and agree to live in a democracy, I expect that I'll be very inclined to accept. Maybe afterwards, if I see it's not working out, I may still consider guerrilla resistance down the line, but I don't see the benefit of fighting and most likely dying just for the sake of def…

Yes and its much more rational to see that the invaders are natural born liars and they installed puppet dictatorships while talking "democracy" and very literally a few days ago backstabbed and invaded you while in the pretense of doing peace negotiations. Logically for an Iranian the most rational response would be to always kill Americans or Israelis in this case.

> 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?

Re: Missile defense is NP-complete

#392

Post by esseph »

lumost wrote: post #226
dlisboa wrote: post #55

Earlier quoted context omitted.

There is an assumption here that the value in improving defenses is the same as improving offensive weapons. That is not the case in the assymetry that drones provide and Russia is the first example. Russia has not been able to improve AA capabilities to the point where it's "safe", for any definition of the word, neither has Israel. Israel and Gulf states often tout over 90% interception rate yet it's really at the…

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…

> The US makes ~50k artillery shells a month at a cost of about 10k per shell.

Closer to $3000. Pre-2022 it was around $800/shell for standard 155mm HE.

Re: Missile defense is NP-complete

#393

Post by esseph »

andrewflnr wrote: post #277
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…

I think that what makes it not WWI is that not even trenches really save you from precision munitions.

Trenches didn't save you from artillery then either. By far the most casualty producing weapon.

Re: Missile defense is NP-complete

#394

Post by wat10000 »

jandrewrogers wrote: post #313
wat10000 wrote: post #306

Earlier quoted context omitted.

It doesn't matter if it's the only option if it's not possible to do it. Maybe it is possible. It does seem like it may be possible to defend against cheap drones with cheaper systems. Use lasers or good old-fashioned projectile guns instead of interceptor missiles. For defending against proper missiles, I don't see how it's possible with any near-future tech. Guns and lasers don't work. You have to use a missile and…

The US Navy is largely responsible for long-range ballistic missile defense, since you have to cross an ocean to hit the US. They also have among the most sophisticated missiles for that purpose, capable of killing an ICBM at apogee. The inventory of these missiles is much larger, every destroyer carries them, and recent variants are often considered the most competent of the various ABM platforms out there. These co…

Are they going to be deploying these into the arctic? I guess being ice free year round will at least help with missile defense.

Re: Missile defense is NP-complete

#395

Post by elzbardico »

rendang wrote: post #290
elzbardico wrote: post #278

Earlier quoted context omitted.

Every country that has a opposition diaspora says the same stuff you're saying here. For what is worth, you could be from a family of Savak secret police members. And frankly that's not how it looks to me.

Every country's diaspora claims their country is ruled by Shia Muslims?

It is kind of funny, and I am not a muslim, but I am curious enough about history of religion to get absolutely baffled by this demonization of Shia.

Shia is actually way more moderate and compatible with western values. Most terror attacks in the west actually are linked to wahabbism (a more radical sunni variant) than to Shia Islam.

Re: Missile defense is NP-complete

#396

Post by esseph »

breppp wrote: post #345
tmnvix wrote: post #244

Earlier quoted context omitted.

I haven't seen imagery of damage to Israeli airbases, but plenty of imagery showing damage to US military bases. e.g. https://www.youtube.com/watch?v=o0cIOMVBSbU . Worth keeping in mind that in the case of Israel, censorship is very effective. From the Iranian perspective, the overall strategy seems to have been: 1. Deplete intercepter stock and probe US/Israeli defences using large amounts of older less accurate mis…

> comparison US ability to increase pressure now seems limited to threatening major war crimes (wiping out Iran's power grid and putting the country into blackout). Not to say many of Iran's actions haven't also been war crimes. US can destroy the entire Iranian economy that rests on oil. The only thing that stopping them right now seems like a fantasy by Trump that post-war Iran will become a Venezuela. Iran could t…

> Iranian ballistic missile capability, at least the long range one is limited by its amount of launchers, and these are also hunted rather effectively.

The island tunnels holding many of these are problematic, which is why we are deploying troops to go tunnel hunting on the islands in the Straight.

Re: Missile defense is NP-complete

#397

Post by elzbardico »

kochikame wrote: post #334
rendang wrote: post #290

Earlier quoted context omitted.

Every country's diaspora claims their country is ruled by Shia Muslims?

No, he or she is saying that even Americans who have moved overseas could be heard to complain about the "fascist" authoritarians in power in the US now. They would sound functionally identical to an Iranian emigrant talking about Iran; only the details would differ

More to the point. Presume Trump cancelled elections and became a dictator. Then a popular revolt overthrows the MAGA dictatorship, starts persecuting MAGA bureaucrats and leaders. Like in any revolution excesses would happen, the economy would, at least temporarily, take a nose-dive, basic services would stop, and so on.

In such a situation, lots of people would presumably leave the US to form a diaspora. Some of those of course, would have been MAGA people directly culpable in the former illegal power grab by trump.

The Sha was not a loved wise leader, he was also a brutal dictator who directed a Comprador elite at the expense of the majority of the persian people. Some of the Iranian exilees just want to go back to act as colonial administrator for the western world like they did before the revolution.

Even if you consider the Islamic Republic evil, you need to be careful before enthusiastically buying a narrative from one side, because a lot of times politics is just the eternal fight of evil against evil.

Re: Missile defense is NP-complete

#398

Post by dlisboa »

LadyCailin wrote: post #349
blitzar wrote: post #337

Earlier quoted context omitted.

> stored military equipment that has a long shelf life Given the pace of advance and changes in strategy, high production capacity is probably more beneficial than inventory.

Maybe, until your production facility is destroyed. Storage is an easier problem to distribute than production.

Production is not a hard problem. Iran, a heavily sanctioned country, already has drone production in other countries. That's assuming no other country would want to sell them their own drones to boost their domestic industry, like Turkiye has been doing for Ukraine.

Most of the Iranian drones are quite sophisticated for what they need to do. On a pinch they could replace many of the non-critical components for cheaper parts. They don't need composite materials if they were simply trying to outproduce. Meaning their production facilities could be much simpler than they are currently and still sustain enough output to matter.

Re: Missile defense is NP-complete

#399

Post by myrmidon »

WalterBright wrote: post #322
YeGoblynQueenne wrote: post #271

Earlier quoted context omitted.

Shahed drones have a maximum range of 25000 km [bbc_1]. The distance from e.g. Isfahan to Tel-Aviv is ~1592 km [google]. Shaheds can reach Israrel from Iran. As to them all being intercepted, in the 12-day war that seemed to be the plan, i.e. force Israel to waste interceptors on cheap drones [bbc_2]. That seems to have changed in the current conflict. _______________ [bbc_1] With a maximum range of 2,500km it could…

During WW2, the British used Spitfires to shoot down V1s. The V1s, pushed by a simple pulse jet, I presume are much faster than the drones. So some WW2 aircraft could be re-armed and used to shoot them down cheaply. The British also employed a belt of radar-guided flak guns to shoot them down. I don't hear any comparisons with the V1s, so my idea must be stupid, but I'm not seeing the flaw in it.

I think a big difference is that asymmetry has grown a lot: The modern drone is much cheaper than any manned aircraft (while V1/V2 needed comparable or greater industrial input compared to fighter planes).

If you want to scramble manned fighters (even WW2-style ones!) every time cheap drones are launched then the pure material cost per intercept might be acceptable (no guarantee here: you need more fuel and your ammunition is potentially more expensive than the drones payload, too), but the pilot wage/training costs alone ruins your entire balance as soon as there is any risk of losing the interceptors (either from human error/crashes or the drone operator being sneaky).

Big problem with stationary AA is probably coverage (need too many sites) and flak artillery is not gonna work out like in the past because the drones can fly much lower and ruin your range that way.

Re: Missile defense is NP-complete

#400

Post by donkeybeer »

falcor84 wrote: post #391
donkeybeer wrote: post #361

Earlier quoted context omitted.

Yes and its much more rational to see that the invaders are natural born liars and they installed puppet dictatorships while talking "democracy" and very literally a few days ago backstabbed and invaded you while in the pretense of doing peace negotiations. Logically for an Iranian the most rational response would be to always kill Americans or Israelis in this case.

> 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.
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