The argument I’ve heard against stopping a missile with a missile is it is like you are ‘hitting a bullet with a bullet’.
But even if an ICBM is going mach 10, why can’t you create a cluster bomb consisting of multiple small nukes each filled with shrapnel, and use that to basically obliterate anything within a 20-50 mile radius? The shrapnel would in theory tear into the missile and make it non-functional.
Obviously, if it were that easy then we would have the technology to do it. So why is that an unworkable solution?
ABM systems with nuclear armed interceptors are definitely a workable solution, at least relative to the debate of how workable any ABM systems are. That’s how the Russian A-350 (Nato ‘Galosh’) system worked until recently (at least), megaton range warhead for exo-atmospheric intercepts and the US Safeguard system also (Sentinel missile ~5mt megaton warhead for exo, Sprint missile ~1kt nuclear warhead for endo-atmospheric intercept). The basic reason subsequent ABM’s have been non-nuclear is that there’s no longer any intention of developing a system which can stop most of a mass US/Russian scale ICBM/SLBM attack in all out nuclear war, which was at least contemplated when the earlier systems were first designed, though later deemed impractical. Subsequent systems have been conceived from the start to stop a relatively few warheads. If they could do this, it was a more serious drawback to have nuclear warheads still going off, those of the interceptors. Similarly the reluctance to have any more nuclear explosions led to the test ban treaty which would make it impossible now to fully test such a system. That actually goes for ICBM/SLBM’s also. But there’s no way to have a highly destructive ICBM without a nuclear warhead. You just have to trust simulations and old test data in lieu of a full end to end test of missile, re-entry vehicle and warhead. In case of ABM’s you can (arguably at least) come up with a practical system without a nuclear warhead, which you can then fully test to prove it.
First, there’s the problem of detonating multiple nukes in the atmosphere.
Second, by the time the shrapnel spreads out over a 20-50 mile distance, it’s to spread out to do any good. Also, it would have to be detonated somewhere over the incoming missile because while the shrapnel spreads, it falls.
As noted above, nuclear interceptors certainly would work, and the Russians have had a limited system deployed for something like 40 years. The US made a policy decision some time ago that nuclear armed interceptors were not worth it, and thus there hasn’t been any significant reserach into them in a couple decades at least.
Note that the systems that had been developed used the blast of a weapon to destroy exoatmospheric threats. There wasn’t any idea of sending random bits of metal over a thousand square miles to destroy warheads the size of barrels. I mean, come on.
Corry El has already provided an accurate summary of previous nuclear-armed anti-ballistic missile (ABM) systems; the only thing I can add is that these weapons are configured differently from nuclear weapons designed for destructive airburst or hardened facility attack weapons to minimize blast effects. The W71 warhead used on the LIM-49 ‘Spartan’ midcourse interceptor was designed for high X-ray yield intending to destory the guidance and arming system on incoming weapons outside the atmosphere; however, depending on altitude it would also generate a singificant amount of electromagnetic pulse. The W66 warhead on the Sprint terminal phase interceptor was designed for high neutron yield and very low X-ray yield, intending to initiate prompt fission in the incoming weapon causing it to fizzle (generate only a small amount of energetic yield before blowing itself apart) but producing comparatively small blast effects. Both weapon systems were originally designed as part of the Sentinal program, designed to protect critical resources and strategic facilities against a broad attack (on the scale of a few hundred missiles); the later Safeguard system was specifically limited to protecting the the Minuteman ICBM fleet as a point defense system. Only one facility was ever operationally established (the Stanley R. Mickelson Complex near Grand Forks, ND, to protect the 321st Strategic Missile Wing at Grand Forks AFB. Planned sites to provide protection for the 341st MW at Malmstrom AFB in Montana and the 351st MW at Whiteman AFB in Missouri were never completed, at the Mickelson Complex was disestablished after only a few months of service because of projected cost and operatonal problems.
The o.p. mentions the notion of destroying the incoming weapons with shrapnel produced by a nuclear blast, but in fact the intense radiation would reduce any solid shrapnel coming from the weapon itself to a highly energetic plasma, and such blast effects would not guarantee disabling or destroying the weapon, which of course is encased in a reentry vehicle (RV) which is specifically designed to survive the high heating and dyanmic effects of reentry. A blast may just push it off course, causing a weapon to miss the intended target but possibly fall upon a city or other resource. The highly enriched fissile material suitable for use in nuclear weapons ([SUP]235[/SUP]U and [SUP]239[/SUP]Pu) is also very expensive to produce and handle, and making a “cluster bomb consisting of multiple small nukes” would be very expensive to build and maintain (whithe, again, is one of the reasons why the Safeguard system was ultimately abandoned).
In any case, it is not necessary to use a nuclear-armed interceptor. While the interception of an incoming ballistic missile or RV is technically challenging, it is feasible and has been demonstrated with a reasonable degree of reliability for years. (During testing of the Sprint system, they found that the radar had to be ‘detuned’ because the intercept was prone to physical interception of the target rather than just passing within the required proximity.) With the guidance capability in modern electronics, being able to guide a kinetic kill vehicle (KKV) to intercept an object on a known trajectory is not the major challenge. The greater difficulty is discrimination of legitimate threats and having a command, control, and integration (C[SUP]3[/SUP]I) capability which is able to detect and respond to threats in real time. This is especially challenging with the current Ground-Based Midcourse Defense (GMD) system because the Sea Based X-Band Radar vessel which is supposed to provide tracking information has spent most of its time in Pearl Harbor undergoing testing and maintenance, and its general seaworthiness is doubtful. The US currently relies on the aging BMEWS and PAVE PAWS ground based early warning radar system, and the SBIRS and STSS satellites for precision tracking; however, all of these systems have limitations and except for STSS were not designed to be integrated into the GMD system. There have been problems in the past with the seeker heads on KKVs not properly tracking the weapon, but these seem to issues with poor design rather than fundamental limitations of the technology.
In summary, we don’t have nuclear-armed interceptors because we don’t need them, they are cost prohibitive, and have substantial deleterious effects that make them poorly suited to the role versus kinetic intercept systems, and the fundamental problems with existing ABM systems pertain more to tracking and system intergraton than the ability to intercept a known threat.
The only small tidbit not thoroughly covered up-thread is that detonating a nuke in the very high atmosphere / low space has the effect of really trashing that area for radar tracking for a period of minutes to hours. In effect you create a large long-lasting hole in your own radar coverage.
An attacker could exploit this by sending in one warhead, knowing you’ll fire a nuke at it and blind yourself. Then they send the rest of their arsenal hurtling over the horizon and you can’t see to shoot. Negating essentially all your investment in defensive systems for the price of one enemy ICBM that may have been nothing but decoy(s).
Interesting. But then, couldn’t an enemy just do that himself anyway? Fire a nuke that detonates in space, to blind US radars for a while, and send more follow-up nukes during that window of opportunity.
One thing not yet mentioned is the potential effect in a multipolar nuclear world - say the US attempts to intercept a North Korean ICBM with nuclear weapons in the high atmosphere or just above the atmosphere.
Looking from the Russian or Chinese perspective - did the US just launch a blinding strike to confuse radar and early-warning systems over the Pacific? Can we assume the Russians and the Chinese also observed the North Korean launch and perceived it as the same threat the US observed (as opposed to say, research rockets) - would Russians believe it if the Americans claimed it was to foil a North Korean attack?
Adding nuclear warheads to the interceptors really complicates things even pre-use - are those nuclear-armed defensive Anti-Ballistic Missiles? Or are they offensive Intermediate-Range Ballistic Missiles and a violation of the INF treaty? (From the Western perspective, the answer is considered clear, but I doubt the Russians or Chinese would give the same answer.)
Yes. I think that’s what Russia was afraid was happening to them during the Norwegian weather rocket incident.
And this is a concern even if the interceptors aren’t nuclear-armed. Some of the interceptors aimed at a North Korean ICBM might end up on trajectories that end in Russia or China. From the Russian or Chinese perspective, should they even wait to see what these things are going to do?
I would think that, from the Russian or Chinese perspective, mistakenly interpreting a nuke detonation in space to be a malicious American act (and therefore doing things like nuking America and getting nuked back in return) entails far more horrific consequences than erring on the side of caution; assuming that America isn’t trying to nuke Russia or China.
Plus, in your scenario, North Korea would have initiated the whole thing by launching an ICBM at America, which would probably be detected by Russian or China’s radars, so they’d know just *why *the USA launched a nuke-tipped interceptor.
Yes, they should. The consequences of mistakenly assuming an American attack (when there is no American attack) outweigh the consequences of the other way around.
They do - and the consequences of retaliating for either the Norwegian Rocket Incident or the Able Archer exercise of 1983 would have vastly outweighed the “threat” in either of those incidents.
When it comes to nuclear weapons, it is very dangerous to assume that you know the mind of the person on the other side and can safely detonate your own nukes in space or the upper atmosphere without worrying because you know what they’re going to do.
You don’t know the information they have/don’t have/think they have that isn’t so… you certainly don’t know what they’re going to do.
Imagine, for a moment, that the roles are reversed. The US successfully intercepts a North Korean ICBM over Eastern Russia using a nuclear warhead.
The Russians, in a tit-for-tat, possibly non-lethal exercise, retaliate for the damage to their early-warning systems by detonating a nuke high above Alaska, intending to similarly disable US early-warning systems without killing anyone, but to place an adversary in a similar strategic condition.
Can the Kremlin sit back, safe in the belief that the US reaction will not outweigh the tit-for-tat response they’ve already made?
