Anti-ballistic System

Pretty much nil. Its far too easy to circumvent with decoys, fast boost, and sheer numbers.
 
One I've thought of would be tying MX deployment to ABM deployment. There was much hand wringing on how to deploy such a powerful and potentially survivable missile, so perhaps an interim solution would be putting the missiles under the Spartan/Sprint umbrella.
 
No signing of the ABM treaty by US and SU?


Pretty much nil. Its far too easy to circumvent with decoys, fast boost, and sheer numbers.


I couldn't disagree more.

For starters decoys don't work (anymore); they'll be too easily recognised as just that unless they are amongst others exactly the same weight as a true warhead.
You just as well might add more warheads then.

Your remark with regards to sheer numbers I don't understand;
- anti ballistic missiles are cheaper then ICBM's, so that's an arms race you don't lose. MIRVs however do complicate this but this can be solved by earlier interception.
- the trajectory of ballistic missiles is predictable as long as you have enough calculating power AFAIK. That amount of calculating power was reached in the '50s/60s.

Most of the reasons why all the major countries in the world don't have ABM systems are non-technical (iirc mostly political reasons and treaties which stopped ABM). If you are willing to use nuclear tipped missiles for ABM, it suddenly becomes a lot easier to do. In that case it's achievable in the '60s.

I wouldn't know the importance/existance of 'fast boost' so I hope somebody else responds to that.

As far as I know, apart from the American projects, there already is an existing ABM system, which has been around for decades; in Russia.

And finally; if your reply was correct, why are the US and Russia investing in just that, with about a dozen countries following?
 
FlyingDutchman said:
For starters decoys don't work (anymore); they'll be too easily recognised as just that unless they are amongst others exactly the same weight as a true warhead.
You just as well might add more warheads then.
First, I doubt that's true while the warheads and decoys are outside the atmosphere. They will all fall along essentially the same path (allowing for differences in ejection etc.) since the acceleration by gravity of an object in near-Earth space is relatively unaffected by the object's mass (the Earth being many orders of magnitude larger), and of course there's no atmosphere to affect them with friction and drag. Once they hit the atmosphere, you have a rather short window of interception; a few seconds IIRC.

Second, even if it is true, a decoy with the exact same mass will likely be rather cheaper than an actual warhead. Thus, you could quite possibly break the ABM cost profile and saturate them with relatively cheap decoys while your expensive warheads sail through unharmed.

Third, you can use active decoys (ECM etc.), too, and just screw up their targeting systems so they can't shoot anything anyways.

The problem with saturation is that the powers had lots of nukes before they had lots of ABMs; so, the opposing power (assuming one side is building ABMs) might very well be able to build more nukes (and decoys) fast enough that the number of ABMs and number of targets will not be equal for some time; and of course since nukes are rather destructive, and ABMs not entirely reliable, you'll want more ABMs than nukes for a reliable shield.

FlyingDutchman said:
the trajectory of ballistic missiles is predictable as long as you have enough calculating power AFAIK. That amount of calculating power was reached in the '50s/60s.
Which is why there was some talk about designing maneuverable warheads (the so-called MARV) in the '80s, IIRC. Much harder to track accurately. There's always FOBs and the like if you really want to get serious.

FlyingDutchman said:
And finally; if your reply was correct, why are the US and Russia investing in just that, with about a dozen countries following?
Silly political directives? Seriously, though, the current ABM systems being developed in the US have a far different mission from a nation-wide Cold War-era shield. For the larger scale systems, the idea is to defend the US against a few ICBMs launched by a rogue power. Defeating the entire Russian arsenal (say) is utterly beyond them. Similarly, the smaller-scale systems are designed to defeat a few tactical BMs and protect rather small areas. They're just incapable of beating an ICBM, but very useful if you're getting Scuds or the like lobbed at you.
 
Second, even if it is true, a decoy with the exact same mass will likely be rather cheaper than an actual warhead. Thus, you could quite possibly break the ABM cost profile and saturate them with relatively cheap decoys while your expensive warheads sail through unharmed.

It's not the cost of the warheads but rather the cost of the rockets. If you can afford the boost capacity for an inert decoy of equal mass to a warhead, then you can afford an actual warhead. Decoys are only of use for the period outside of the atmosphere because you can use balloons.

Third, you can use active decoys (ECM etc.), too, and just screw up their targeting systems so they can't shoot anything anyways.

This can't work. There's no way you are putting ECM on an ICBM powerful enough to deal with the massive radars and sheer power a ground based ABM control has.
 
When the ABM treaty was signed there were so many ways to degrade an ABM sheild that the US and USSR gave a comprehensive system up as a bad joke. To protect cities exo-atmospheric interceptors are needed, and these are the most sucesptable to decoys, chaff and even bits of rocket body/bus and 'blocking' nuke blasts which blind radars for crucial seconds in an engagment where every second counts. This is before MIRVs, FOBS, depressed trajectory SLBMs and low level bombers are bought into the ABM vs ICBM equation. Sprints are better, they can discriminate out the chaff and decoys etc but of course they involve multiple thermonuclear explosions well within the atmosphere.

Personally I think that with continual refinement the 70s ABM systems could evolve into something quite useful, after all the Sprint's kinetic performance is bloody amazing. The radars could become faster and have more discrimination, other tracking systems could be networked into the ABM system, the missiles could be made more accurate and warheads made smaller and thus the whole system becomes more useful.
 
I think OTL saw both powers have an ABM system.

The US had the NIKE ZEUS system for a few years to defend against attacks on the missile fields in the Midwest, while the Soviets have a system in place to defend Moscow itself.

(They also cheated on the ABM Treaty--at the very least, they had more radars than they were allowed and at most, lots and LOTS of ABM-capable missiles.)
 
(They also cheated on the ABM Treaty--at the very least, they had more radars than they were allowed and at most, lots and LOTS of ABM-capable missiles.)

It's not so much that they cheated. It's just that when you build a SAM with the performance and range to deal with high altitude/high speed aircraft, you have almost by definition an ABM capable missile.

I've read that the US went to a lot of trouble to degrade the performance of the Patriot just so they wouldn't violate the treaty. The latest, PAC-3? 4?, version is really just putting back in what was taken out. The Russians just never worried about it.

To the OP. The 80's is probably to late for the US. By that point we had already dismantled the Army Air Defense Command (ARADCOM) and scrapped the Nike missle batteries that would have been the logical starting point for an ABM system.

If the US had kept the system in the 60's and continued to upgrade it, Nike-Ajax-->Nike-Hercules-->Nike-Zeus-->Nike-X-->Sentinal, then we could have a comprehensive ABM system in place by the 1980's or 90's. Keeping them nuclear tipped just makes it that much easier to do.

Here's are some pretty good refence sites for your enjoyment.
Nuclear ABMs of the United States
Nike Site Locations & Status
Stanley R. Mickelsen Safeguard Complex
 
If the superpowers had sought to build comprehensive ABM systems they would have gone broke and gotten very little real protection. As said elsewhere a comprehensive system would be too easy to saturate or otherwise defeat. A limited system, as allowed by the original ABM treaty, with limited goals could probably have met it's goals and given something to develop. ABMs at an ICBM site and the national capital can play a part in national nuclear strategy, allowing time for tactics such as 'launch under attack' to occur while reducing the risk of 'decapitation' or a crippling counterforce strike.
 
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I couldn't disagree more.

For starters decoys don't work (anymore); they'll be too easily recognised as just that unless they are amongst others exactly the same weight as a true warhead.
You just as well might add more warheads then.

Not at all true. Exoatmospheric there's absolutely no reason for mass to be a factor and soft countermeasures such as chaff are perfectly useable (and still equipped on MMIII as part of its penaids). Endoatmospheric, as long as your drag/mass ratio (which determines rate of descent) and radar signature are sufficiently similar I can't see an issue, and the drag/mass ratio doesn't require equivalent mass (Blue Streak was intended to carry 20-30 such decoys made out of fiberglass, with radar reflectors to produce a signature similar to the warhead, and possibly equipping low power radar jammers as well. Source: Britain and Ballistic Missile Defence 1942-2002 page 116).

Your remark with regards to sheer numbers I don't understand;
- anti ballistic missiles are cheaper then ICBM's, so that's an arms race you don't lose. MIRVs however do complicate this but this can be solved by earlier interception.

Mmm, do me a favor and provide some numbers please on a "per warhead lofted" and "per pK(x) of incoming RV killed" where x is the probability of killing the incoming target, with cost figures adjusted for the fact that this might require the use of more than one missile per warhead. For the record, S-300 claims 0.7 pK of much easier to intercept tactical ballistic missiles.

As for intercepting MIRVs earlier, boost-phase intercept is plausible only in the realm of fantasy and can actually be entirely circumvented with fast-boost missiles.

Actually, I'll do you a favor. Atomic Audit, Table 2-3, page 149-150:
Minuteman III, 840 produced, acquisition cost 28,140 million (1996 dollars)
MX, 102 produced, 19,320 million cost
Sprint, 112 produced, 2,350 million cost
Spartan, 72 produced, 2,760 million cost

Per warhead cost: 11.167 million and 18.94 million
Sprint cost 21 million per missile and Spartan cost 38.3 million.

Even assuming a perfectly planned and operated defense with a pK of 1, the costs tremendously favor the offensive. Even a perfect defense requires that it achieve 2-3 kills per missile launched in order to break even.

- the trajectory of ballistic missiles is predictable as long as you have enough calculating power AFAIK. That amount of calculating power was reached in the '50s/60s.

And that's entirely irrelevant. By the time it shows up on radar its already released all warheads and decoys (and probably at least one chaff cloud). Additionally, that is with low resolution radars, further complicating the problem of discrimination. Furthermore, it is possible, through active or passive means (rockets or aerodynamic design) to conduct evasive maneuvers that take advantage of ABM systems that have been committed to distant interceptions after burnout ("Galosh was believed to be committed to a predicted intercept point after sustainer burn-out (about 66 seconds). It could therefore be defeated by manoeuvring warheads in the remaining time before intercept (about three minutes), though the high lethality of a nuclear burst in space might in part compensate for this. It appeared that little if any work had been done on overcoming penetration aids." Britain page 127).

Lastly, it is also possible to design MaRVs that entirely circumvent ABM systems which can be used to destroy their radars and so cripple their capability against further waves of missiles.
"But an even more audacious program was two Air Force MaRV programs over 1961-1964 that saw Mach 10+ vehicles doing sharp turns while approaching their targets. During this period, the US designed MaRVs that came in at such low altitudes (500-1,000 feet) on their final (one minute) low-altitude run-in to their target that they would have needed terrain-avoidance radar to keep them from hitting elevated terrain while approaching their targets. The US pioneered hypersonic control flaps, nosetips and homing sensors for such MaRVs. However, none ever made it into service despite impressive, rapidly paced flight tests." Near-Term BMD Defenses Against Chinese Anti-Ship Ballistic Missiles Fitted with MaRVs


Most of the reasons why all the major countries in the world don't have ABM systems are non-technical (iirc mostly political reasons and treaties which stopped ABM). If you are willing to use nuclear tipped missiles for ABM, it suddenly becomes a lot easier to do. In that case it's achievable in the '60s.

And V-1000 made a conventional kill in 1961, so what's your point? The problem with ABM has never been with the technical problem of hitting individual warheads in isolation, the problem is the entire system.

I wouldn't know the importance/existance of 'fast boost' so I hope somebody else responds to that.

Fast burn ICBM. Never built, but studies indicated that they could if need be, and they released their warheads before even exiting the atmosphere, rendering them invulnerable to orbital boost-phase intercepts.

As far as I know, apart from the American projects, there already is an existing ABM system, which has been around for decades; in Russia.

And it was crap, not capable of dealing with anything more than a minor attack.

"Furthermore, tests of System A [sic] clearly indicated that the ABM system could not defend Moscow against a massive attack without substantial changes. The main problem was the system's inability to intercept ballistic missiles with independently targetable reentry vehicles and ABM penetration aids" Russian Strategic Nuclear Forces page 414-415. Same source indicates design for a maximum simultaneous intercept of six to eight targets.


And finally; if your reply was correct, why are the US and Russia investing in just that, with about a dozen countries following?

The US because of some Congressional hawks and defense lobbyists (GBI still remains a completely worthless program that is the single largest expense in the DoD budget), Russia is maintaining their A-135 system, and nobody else is working on an anti-ICBM force. India has is working on an ATBM project and Israel is working on an anti-MRBM project in conjunction with the United States. Both of those systems are against very simplistic and decades old technologies however. Japan is working with the US on SM-3, Block II of which is supposed to have a minimal ICBM intercept capability, but that's all that comes to mind.

MerryPrankster said:
(They also cheated on the ABM Treaty--at the very least, they had more radars than they were allowed and at most, lots and LOTS of ABM-capable missiles.)

CIA analysis of the radars indicated they were not capable of being used for battle management and please tell me you're not believing that nonsense about the SA-5 being capable of being used against ICBMs.


It's not so much that they cheated. It's just that when you build a SAM with the performance and range to deal with high altitude/high speed aircraft, you have almost by definition an ABM capable missile.

No, you don't. There are major differences in pretty much all aspects of the engagement and increased capability against one type of target results in a decrease in capability towards other types of threats.

I've read that the US went to a lot of trouble to degrade the performance of the Patriot just so they wouldn't violate the treaty. The latest, PAC-3? 4?, version is really just putting back in what was taken out. The Russians just never worried about it.

If they did so, it was entirely pointless because the ABM treaty doesn't restrict anti-tactical ballistic missiles, only missiles intended to intercept strategic ballistic missiles, and the Soviets deployed anti-tactical ballistic missiles in the S-300 system.
 
There were just too many launchers and warheads for a comprehensive ABMs shield to be evfen remotely practical. The US had 11,000 warheads and the USSR had 8,000 in 1982, that would require a massive system needing more defensive missiles that the opponents offensive arsenal. These ABM sites would then prove tempting targets for non ballistic missile attack; bombers and SLCMs.
 
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