3 ms·

Your math is a little off on the prices. Recall that the GBSD will release 10-12 MIRVs, which means the ABM shield has to intercept 10-12 targets, not one, for

Your math is a little off on the prices. Recall that the GBSD will release 10-12 MIRVs, which means the ABM shield has to intercept 10-12 targets, not one, for every ICBM. And standard operating procedure is to fire 4 interceptors at each target to ensure a hit. That means for each GBSD we need 40 interceptors, making it over 5 times more expensive to intercept a GBSD than the GBSD itself. Of course, just comparing missile costs isn't the best, they do not operate on their own. Each interceptor needs a silo, ground crew, intercept radars, etc. ICBMs need silos and ground crews also. The cost to operate an ICBM or ABM shield over its lifetime will dominate the total costs compared to the initial missile price.

chipsa 4y ago
GBSD is currently programmed to be a single warhead missile [0]. The fire plan for GBI is "shoot-shoot-look-shoot-shoot". There's no requirement for the second "shoot-shoot" to actually occur, and in case of a mass launch, wouldn't occur because we'd run out of GBIs first. GBIs and GBSD do both need silos and ground crews, but the state of them is to a different degree. GBI needs a silo to protect it from weather, but it doesn't necessarily need to be a nuclear hardened silo, because if it comes to that, the silo should already be empty. The ICBM silo does need to be hardened against nuclear weapons. Similarly, the ground crew for the entire ABM field can be centralized, because you don't need them to be multiply survivable to launch after the end of the world, but you do need for an ICBM launch control center to be redundant and nuclear hardened. Each interceptor shares radars, however, so you don't need more with more interceptors. It's a fixed cost for the entire system, given the region you're looking at. This is semi-irrelevant, as our opposition doesn't pay US prices, and their ability to afford more ICBMs is not related to US prices. The only countries which do pay US prices are the US and UK. Also, this assumes the ABM shield needs perfection. If you're trying merely to save as many lives as possible, then the existence of the ABM system requires the opponent to prioritize which targets they want to hit. The high priority targets will need to have many warheads targeted on them, while the lower priority targets won't have any, because they don't have the budget for that. And the more warheads we can intercept, the more warheads they have to drop on their high priority targets, because they don't know which ones will actually get intercepted. If we can intercept on average 15 warheads (75% effectiveness with "shoot-shoot"), then they have to drop 16 warheads on each high priority target. If we double the number of warheads we can intercept, then they need to double the warheads they drop on their high priority target. This is why the UK strategic deterrent is roughly targeted only on Moscow, according to open-source knowledge, instead of the early 60s version that hit most of Russia. [0]: https://crsreports.congress.gov/product/pdf/IF/IF11681 https://crsreports.congress.gov/product/pdf/IF/IF11681 > The Air Force plans to deploy the GBSD (Sentinel) with one warhead per missile
- openasocket 4y ago
  Thanks for the info on the GBSD, I wasn't aware of that. I'm actually surprised, I thought the general trend was towards MIRVs. Yeah, I'm willing to concede the math is a lot more complicated than just "ABM is more expensive than nukes" and I could well be wrong on that point. I suppose if we really wanted to get to the bottom of it we would have to compare the ABM against the current Russian/Chinese arsenal, think about the relative costs of road-based/silo-based/sub-based missiles and their risks, compare rubles and dollars using something other than naive conversions to account for relative purchasing power, consider what impact decoy re-entry vehicles have on the equation, and a bunch of other factors. I think my original argument that ABM is inherently destabilizing stands though.
  - chipsa 4y ago
    New START has warhead limits, as well as missile limits, and the US has decided it'd rather allocate the warheads to bombers and SLBMs instead of ICBMs. The ICBM force is in a sense, a strategic decoy: they're hardened to make you have to expend warheads on them, but the relative lack of warheads means that if you allocate more than one to take each out, you're probably not coming out ahead. But you have to honor the threat, so you can't just not hit them. So, they take 450 or more warheads from what you would otherwise want to hit.

chipsa 4y ago

GBSD is currently programmed to be a single warhead missile [0]. The fire plan for GBI is "shoot-shoot-look-shoot-shoot". There's no requirement for the second "shoot-shoot" to actually occur, and in case of a mass launch, wouldn't occur because we'd run out of GBIs first. GBIs and GBSD do both need silos and ground crews, but the state of them is to a different degree. GBI needs a silo to protect it from weather, but it doesn't necessarily need to be a nuclear hardened silo, because if it comes to that, the silo should already be empty. The ICBM silo does need to be hardened against nuclear weapons. Similarly, the ground crew for the entire ABM field can be centralized, because you don't need them to be multiply survivable to launch after the end of the world, but you do need for an ICBM launch control center to be redundant and nuclear hardened. Each interceptor shares radars, however, so you don't need more with more interceptors. It's a fixed cost for the entire system, given the region you're looking at. This is semi-irrelevant, as our opposition doesn't pay US prices, and their ability to afford more ICBMs is not related to US prices. The only countries which do pay US prices are the US and UK. Also, this assumes the ABM shield needs perfection. If you're trying merely to save as many lives as possible, then the existence of the ABM system requires the opponent to prioritize which targets they want to hit. The high priority targets will need to have many warheads targeted on them, while the lower priority targets won't have any, because they don't have the budget for that. And the more warheads we can intercept, the more warheads they have to drop on their high priority targets, because they don't know which ones will actually get intercepted. If we can intercept on average 15 warheads (75% effectiveness with "shoot-shoot"), then they have to drop 16 warheads on each high priority target. If we double the number of warheads we can intercept, then they need to double the warheads they drop on their high priority target. This is why the UK strategic deterrent is roughly targeted only on Moscow, according to open-source knowledge, instead of the early 60s version that hit most of Russia. [0]: https://crsreports.congress.gov/product/pdf/IF/IF11681 https://crsreports.congress.gov/product/pdf/IF/IF11681 > The Air Force plans to deploy the GBSD (Sentinel) with one warhead per missile

openasocket 4y ago
Thanks for the info on the GBSD, I wasn't aware of that. I'm actually surprised, I thought the general trend was towards MIRVs. Yeah, I'm willing to concede the math is a lot more complicated than just "ABM is more expensive than nukes" and I could well be wrong on that point. I suppose if we really wanted to get to the bottom of it we would have to compare the ABM against the current Russian/Chinese arsenal, think about the relative costs of road-based/silo-based/sub-based missiles and their risks, compare rubles and dollars using something other than naive conversions to account for relative purchasing power, consider what impact decoy re-entry vehicles have on the equation, and a bunch of other factors. I think my original argument that ABM is inherently destabilizing stands though.
- chipsa 4y ago
  New START has warhead limits, as well as missile limits, and the US has decided it'd rather allocate the warheads to bombers and SLBMs instead of ICBMs. The ICBM force is in a sense, a strategic decoy: they're hardened to make you have to expend warheads on them, but the relative lack of warheads means that if you allocate more than one to take each out, you're probably not coming out ahead. But you have to honor the threat, so you can't just not hit them. So, they take 450 or more warheads from what you would otherwise want to hit.