[Oberon]

Originally Posted by Mr Quatro

What defensive weapon can you fire at these NK missile launches?

What ship borne weapon would knock one down?

We don't have any do we?

I thought the US missile defense system in Hawaii on Kauai and the one in Alaska was to target warheads on their points of reentry.

But these missiles fall apart over the Pacific so that won't work on them. These two destroyers that just had a crash with cargo/freighters had some kind of Aegis system I think they call it ... would that knock down a NK missile launch?

https://en.wikipedia.org/wiki/Aegis_...Defense_System

That's the other kicker in this equation, by the time the Hwasong-12s are passing over Japan, they are travelling at an altitude of around 500km. The SM-3 which is the missile used in the AEGIS system has (AFAIK) never been tested at that altitude. The IIA is meant to have some capability against ICBMs, but the maximum it's officially designated for is IRBMs. If I recall correctly the highest contact that the SM-3 has intercepted was the satellite back in 2008 and that was at an altitude of 240km.

The AEGIS ships are there for stuff coming in to hit Japan, and even then it's a bit of a crapshoot, and the system isn't infallible. Likewise with THAAD. One thing that the DPRK could do to bypass all the THAAD systems deployed in South Korea is just launch from behind them, all the radars and interceptors are pointed north. If a submarine launches SLBMs from behind the THAAD, the THAAD is boned.

Against America there's the Ground Based Midcourse Defence system in Alaska, but that can be overwhelmed since it has a limited number of missiles and it wouldn't just launch one interceptor per ICBM, it would launch multiple ones, which means you just need a factor of ICBMs more than would be salvo launched against you and that is Americas primary defence nullified and they have to hope that the AEGIS can handle the incoming missiles and warheads in the very short amount of time that they'll have to intercept (think of the game 'Missile Command' but on maximum difficulty).

So...yeah, the US isn't invulnerable behind a missile shield, it can get hit, and Japan and South Korea are definitely not invulnerable. They would get hit in a war, and they would get hit hard. Sure, the DPRK would be defeated, the US and its allies would win, that much is a given...but it would be very Pyrrhic.