The North Korea Thread

I don’t see offhand how it’s physically possible to shoot down an ICBM soon after it launches. Unless your antimissile installation is deployed next to the launch site. Your own missile not only has to launch and achieve the same altitude, it has to cover all the ground in between.

THAAD for example only has a range of 200 km and so I assume it can’t possibly reach an ICBM during its launch phase unless the enemy is kind enough to site the missile silo on its border. A Standard missile has maximum range of somewhere between 250 and 500 km and so theoretically could at least cover the ground if there’s a battery around Seoul. But so far as I know the standard missile is meant mainly for CIWS, ie incoming munition interception for slow targets like cruise missiles and aircraft, not for some kind of launch interception of ICBMs. But perhaps there is a Mach 3.5 antimissile system with 500 km range that really is designed to catch an ICBM. I still think a Chinese or Russian ICBM couldn’t possibly be shot down until after it goes ballistic, though conceivably a North Korean one might be caught in time if it is tracked from the moment of launch and a nearby antimissile is ready to catch it.

But what is providing the targeting and tracking information on the ICBM? I imagine some ICBM fired hundreds of kilometers deep in enemy territory is not going to be targetable until it gets pretty high off the ground, at which point I suppose it will be too late to shoot down until it gets most of the way to where it’s going. If the enemy waits for a cloudy day to launch, it won’t even matter if you are lucky enough to have a satellite overhead to maybe spot the thing optically, because by the time the missile gets through a high cloud layer it will I assume be going too fast for an antimissile launch to catch.

IANAExpert on such things, but I would think an interceptor missile is far lighter than an ICBM, allowing for much quicker acceleration. Also, I wouldn’t rely on a single point at launch - any given interceptor will only have a certain range, after which the task would be handed off to another. Also, satellites with IR can look through clouds and smoke. An ICBM would have a very different speed and heat bloom than an aircraft, and I’d imagine detection algorithms take that into account.

It’s not easy and proximity is a big part of it. Basically an ICBM is massive. It’s a big object accelerating fairly slowly (in relative terms of ballistics). Your interception vehicle is much smaller and accelerates to speed much quicker, so while the ICBM is still fighting inertia your smaller missile is already accelerating towards it.

Range and detection are key issues. Also consider the gap in technology at least in relation to DPRK. They’re basically using tech from the 60’s at best, we’re using hypersonic weapons to intercept. Assuming it’s based on SCUDs:

SM-3 Block IIA (intercept missile from an Aegis) speed: Mach 15.25
SCUD speed: Mach 5

Add in time to reach those speeds and you can see how it works, at least in theory. Of course shooting a bullet going 4-5 times the speed of sound with one going 15 times the speed of sound is still far from an easy thing.

Edit: And like Dan said, the second the thing launches there is a very good chance we can detect it and have our interceptor in the air ready to meet it.

Huh, I was looking at the RIM-174, which only has a top speed of Mach 3.5 and a shorter range. I will grant that Mach 15 is fast enough to catch an ICBM within the 700 km range of the SM-3. I’m still not sure how it targets an ICBM hundreds of kilometers away, however.

Mach 15 is insanely fast. I was always impressed by https://en.wikipedia.org/wiki/Sprint_(missile) but that was mach 10, albeit decades ago.

Maybe. Depends on where the sensors are and where the launch site is, among other things. Even digital communications can’t go faster than the speed of light, and there is a perceptible delay in signals travelling long distances–enough to affect something as dicey as a missile interception. There are always ways to compensate for any of this, theoretically. Whether any of it is actually practical remains, luckily so far, a matter of speculation.

Sure, but the speed of light is… really fast with regards to terrestrial affairs.

And external stuff just gets it close enough that it’s own sensors can take over. So you could, in theory, launch it once you detected an enemy launch and guide it to the target’s area and then it will take over. Being off a few fractions of a second doesn’t matter that much until you’re talking about impact, at which point the missile’s system took over and it became irrelevant.

it is, but when you’re talking about relaying information from orbital sensors to terrestrial ground stations, and hence to firing units, it all adds up.

Yeah, including processing time at each stop. Makes sense.

Are you guys suggesting we have 46,000 square miles of North Korea blanketed with radar continuously in order to detect a launch instantaneously? What happens if they use 1930s tech to jam radar frequencies, which at present seems to be working quite well as an ECM technique for Russian planes? All you need for that is some basic electrical components and an antenna.

I would suspect that we have satellites capable of detecting a launch more easily than radar.

Yes, but that’s not useful for targeting an antimissile. You need lock-on for that. Moreover satellite coverage is spotty and irregular because they move so fast and we have a limited number of them.

Yeah, we’re all gonna die.

Well, eventually.

I used to do some technical consulting work for the anti-ICBM joint program back in the mid-90s… basically spending some of the “Star Wars” money that Reagan appropriated in the late 80s as the program lurched zombie-like into a post-Soviet reality.

Our launch-plume detection coverage is pretty comprehensive, and has been since the late 1970s. I would be stunned if the coverage over Asia was not 100% and multiply-redundant.

After a launch is detected by a satellite, it’ll provide coordinates for a radar to get a “lock-on”. Back in the 90s, the “requirement” we were looking to meet was less than six seconds from detection to tasking a targeting radar. I don’t know if they met that goal. Do we have such radars in place near the DPRK, either in South Korea or on nearby ship? I suspect so. How long does it take to orient those radars and lock on? I dunno: Mere seconds? Tens of seconds?

I keep hearing that China is unhappy with deployment of THAAD in South Korea because of the radar requirements, but I know nothing about the technical aspects.

That’s one of the key bits of info I guess. That, and how much time do you need to act on that lock on, and within what time spread, etc.

Eh, none of us are going to answer these questions. We can only hope that someone actually does have an answer, and that someone in command actually understands all of this.

Which, in today’s America, is not necessarily a given.

“There have been a lot of aspects of things that he’s done and said that I’ve found very disturbing. But that stuff has been really upsetting — I feel that he is an affront sometimes to the whole country in the way he conducts himself. And that has been the worst.”

This guy is such a moron.

If the US tears up the deal, then basically we just lose everything we gained.

We won’t be able to reimpose sanctions, because Trump is hated by everyone in the world. Iran already got its money back that the US was holding. So the US is left in a position with zero leverage. Iran can just say, “Ok, deal’s off. We’re going back to making nuclear weapons. Thanks, chump.”

And it’s clear that no one should ever make a deal with the US ever because we won’t honor it.