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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#211

Post by breppp »

dlisboa wrote: post #197
breppp wrote: post #194

Earlier quoted context omitted.

> interception rate yet it's really at the mercy of Iran to not target their most vulnerable sites And what this site and you don't account for, is Iranian rather low missile accuracy. If Israel was at the mercy of Iranian attacks, Iran could have simply struck Israeli airbases to the point they cannot be used, and then stop any Israeli attacks on its territory. It's pretty obvious they don't have the capabilities of…

You're making the same argument I am. If Iran had a small increase in accuracy they could hit targets that'd disable a lot of Israel military and civilian infrastructure. A lot of stuff is getting through. To counter that Israel has to achieve a perfect interception record. The balance is throughly on the side of offensive drone/missile warfare.

I don't think we are arguing the same thing. I am arguing that even without any air defense, Iran would have difficulty hitting its targets in Israel with ballistic missiles due to low accuracy. When adding interception rates they have a real problem in attacking strategic facilities, air bases is a good example, which would be much more important than desalination plants.

You can then see that they shifted to completely attacking large cities, usually with cluster bomblets. The reason is when you are bombing a large area, aim is less of an issue, similar to WW2 carpet bombing

Your post alludes to drones, these do not reach Israel (from Iran) at all and are all intercepted

Re: Missile defense is NP-complete

#212

Post by breppp »

cheney_2004 wrote: post #209
breppp wrote: post #194

Earlier quoted context omitted.

> interception rate yet it's really at the mercy of Iran to not target their most vulnerable sites And what this site and you don't account for, is Iranian rather low missile accuracy. If Israel was at the mercy of Iranian attacks, Iran could have simply struck Israeli airbases to the point they cannot be used, and then stop any Israeli attacks on its territory. It's pretty obvious they don't have the capabilities of…

Iran has successfully targeted countless bases around the Middle East, a lot of this news simply isn’t being covered. Most of these strikes are on static assets like radar, depots, and other structures. If you are thinking about the F35s, strikes that hit runways are repaired in a matter of hours. As for the F35s themselves, they are constantly on the move or simply kept in the air. Service and storage is done on rem…

That's certainly what Iranian propaganda is saying, as if everybody is censoring their great successes. Fact is there is no meaningful reduction in Israeli attacks, while Iranian launching ability had greatly suffered. So these air bases are probably not being hit. Apart from it in the era of OSINT satellite imagery, it is no issue to publicize such damage, I don't know of any such imagery

Regarding the gulf, there the Iranians are having better success as at those ranges intercepting drones is harder and due to the general military ineffectiveness of the gulf nations

Re: Missile defense is NP-complete

#213

Post by orwin »

DoctorOetker wrote: post #145
orwin wrote: post #52

Earlier quoted context omitted.

> total manufacturing capability" is set to decline in any prolonged engagement with an Iran-like nation That was what Russia thought about Ukraine. Effectively, they needed East European tanks and munitions for the first two years, but munitions production ramped up, and now they produce more per year that what they received over two years. A resource-rich country like the Iran that is effectively fight a death war…

> And imho, while Kurds accepting to be betrayed by the US for the third time in less than two decade won't have any real long term impact, an independent Baluchistan can easily destabilise Pakistan. Not to confuse my prediction from prescription, but what prevents all the neighboring (direct or indirect over a sea) nation states from deciding to divide Iran like Germany was during the cold war? Thats not an independ…

Saddam was paid (in chemical weapons, but not only) by the US to invade Iran, it didn't work well for them at the time, despite the MEK helping them with hidden routes and a lot of local support they don't have anymore. The current Iraki leadership isn't stable enough to do the same anyway.

Afghanistan and Pakistan are in a small war that will have some impact on Baluchistan, but official Pakistani ground troops are a no-no, because it will leave ground for the Taliban. Also India invested a lot in Baluchistan biggest port, and Pakistan threatening their investments will probably have them react (India love nothing more than helping Pakistan adversaries). Koweït is too small, Irak Kurds need to secure their autonomous region, and US promised are worth basically nothing. Azerbaijan used Iranian drones and artillery against Armenia like 2 years ago (maybe 3), and Iran apologised publicly after sending a missile to them.

All of this to say: only the US have the manpower and will for a ground invasion.

Re: Missile defense is NP-complete

#214

Post by delichon »

jmyeet wrote: post #85
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.

If you haven't, I'm going to recommend you to listen to an episode of Dan Carlin's Hardcore History , specifically The Destroyer of Worlds [1]. Why? Because it goes into the change in strategic thinking brought on by the atomic age (and, soon thereafter, the thermonuclear age). And there was an element of US strategic thinking that argued for a preemptive strike against the USSR. The episode also goes into the argume…

  With the Russians it is not a question of whether but of when. If you say why not bomb them tomorrow, I say why not today? If you say today at 5 o'clock, I say why not one o'clock?  -- John von Neumann, ~1950
On the one hand he was one of the smartest people in history. On the other, his home country had recently been conquered by the Red Army so he may have been a little biased.

Re: Missile defense is NP-complete

#215

Post by logicchains »

dlisboa wrote: post #153
pc86 wrote: post #132

Earlier quoted context omitted.

What Iranian drone did a trillion dollars in damages? I'm not saying the general thrust of your argument is wrong, quite the opposite. But that's a big number for one drone.

A trillion seems large but it's not that absurd. The drone that shut down 17% of Qatar's LNG capacity is said to have caused 20 billion USD worth of annual lost revenue. They said it'll take up to 5 years to rebuild so that could be 100 billion USD in lost revenue, plus whatever it costs to do the rebuild. A trillion dollars worth of damage seems possible if spread over some years for some countries in the Gulf where…

>The drone that shut down 17% of Qatar's LNG capacity is said to have caused 20 billion USD worth of annual lost revenue.

That was a missile not a drone.

Re: Missile defense is NP-complete

#216

Post by delichon »

marginalia_nu wrote: post #43
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.

The game theory of it is the prisoner's dilemma. Preemtive betrayal is a terrible strategy if there are more than two parties in the game, and they are allowed to cooperate. You have to be one heck of a smooth conversationalist to convince them to take a number and patiently wait in line to be the ones to be attacked next. If you're the guy that the others in the room know shoots first, you're also the guy the others…

The prisoner's dilemma leads to mutual defection as the dominant equilibrium strategy in the one-shot version. Cooperation emerges as the equilibrium on repetition. The Han Solo gunfight is literally the one-shot version. When countries go to war that calculation is more complicated.

Re: Missile defense is NP-complete

#217

Post by wat10000 »

pc86 wrote: post #174
wat10000 wrote: post #78

Earlier quoted context omitted.

Unfortunately, necessity doesn’t imply possibility. It could simultaneously be true that you must build interceptors to protect yourself, and that you can’t build enough. It only makes sense to consider the cost of what’s protected if it’s actually protected. If your million-dollar interceptor protects a multi-million-dollar building from a $100 missile, and then that building is hit by a second $100 missile, was it…

> If your million-dollar interceptor protects a multi-million-dollar building from a $100 missile, and then that building is hit by a second $100 missile, was it worth it? I mean the assumption is that if the first missile hit the building, the second missile would have been fired at something else, right? Still seems worth it at face value especially if there's enough time between the two missiles that there aren't…

My assumption would be that the attacker builds missiles based on the defenses they want to defeat. If you have no defenses, maybe the defender builds 1,000 missiles. If you have 1,000 interceptors with 100% accuracy, then maybe the defender builds 2,000 missiles.

This is why the superpowers mostly scrapped their ICBM defenses in the 70s. The technology worked fine. It's totally doable with 1970s technology if you're willing to put nuclear warheads on the interceptors. But for every ICBM interceptor you built, the other side could build another ICBM for the same cost or less. And you need more than one interceptor per ICBM since they can fail and the each interceptor only covers a small area. Add in multiple warheads on a single missile and decoys and suddenly you might need 10x or more. So the USA gave up on the idea of covering the entire country with interceptors, deployed a few interceptors to protect some missile silos, then shut it down after less than a year. The USSR built out a system to protect Moscow and only Moscow, which is still operational today. However, the British were able to maintain the ability to defeat that system and destroy Moscow with a single submarine, all on their own, never mind what the USA would throw at it.

If you have a certain amount of stuff you can build and you're deciding what to do with that capacity, it's not at all clear that missile interceptors are a good use of that capacity even if you're protecting objects that cost orders of magnitude more than the interceptors cost. It works if you're defending against a far less capable adversary (Israel's Iron Dome against Hamas, USA's GBI system against North Korea) but not with an enemy that's even vaguely close to being a peer.

Re: Missile defense is NP-complete

#218

Post by swat535 »

deburo wrote: post #84
pjc50 wrote: post #46

Earlier quoted context omitted.

Iran has always known that the US is a higher tech nation, but you should not just expect them to surrender on that basis.

That's not what deterrence means. From google: the action of discouraging an action or event through instilling doubt or fear of the consequences. It's meant to avoid conflict altogether, say with China and Taiwan.

Iranian here, you're assuming sanity.

That doesn't work when your opponents pray for death and see martyrdom as victory.

This is genuinely how Shia extremists think. They have nothing to lose and will sacrifice everything and everyone for their cause. They don't care about Iran or Iranians or prosperity of the nation.

Re: Missile defense is NP-complete

#219

Post by wat10000 »

pc86 wrote: post #180
wat10000 wrote: post #140

Earlier quoted context omitted.

That's true, but feels very much like "draw the rest of the owl." And even if you can do it, you'd have to do it against any country that starts to build this capacity that you think might somebody potentially use it against you, even if they aren't currently, unless you're confident that you can destroy their launchers and stockpiles so quickly that they can't be used in any significant number. (And if the USA could…

Yes, it's complicated. There's almost 1,000 generals and officers spread across the US military. They (and the tens of thousands of people directly supporting them) spend a lot of time on these things. Sometimes "draw the rest of the owl" makes sense when you've got 20,000 people actively drawing owls all day every day.

I'm generally sympathetic to the argument that there are a lot of experts doing expert things who know better about these things than some idiot sitting at his computer i.e. me.

But in this particular case, we're in the middle of a war where the owl didn't get drawn and the enemy has successfully launched thousands of drones and missiles at our forces and our allies, causing enough damage to severely disrupt the world economy.

Re: Missile defense is NP-complete

#220

Post by gs17 »

zabzonk wrote: post #3

Oh, I thought this was going to be about the old trackball arcade game. Or perhaps it is? Same sort of rules? The maths is going so far over my head I can't hear the whoosh.

I expected that too, but it's about the inspiration for the game, I guess. I was trying to figure out how you encode computation in the game.
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