When is a first strike not a first strike?
When it's Anticipatory Retaliation.

October 04, 2004

Bunker-Busters and Defense

Bravo Romeo Delta

In response to a call by Hugh Hewitt for posts about bunker-busters I've gone and cooked up something. Couldn't really tell you if it's anything good or not. But hey, since we bloggers evidently have any checks like editors or any sort of journalistic responsibility, I don't feel compelled to actually, you know, edit anything I write, so here goes...

Ok, first off, the role that nuclear weapons play today has precious little to do with the preconceptions that people carry with them from Hiroshima and Nagasaki – for later reference, these explosions were in the 15-20 kilton (kT) range. So, based on this, we have to cover a little tiny bit of background.

The important thing to consider is that in their original incarnation, strategic nuclear weapons were solely about causing what we would now call collateral damage. Since that era, planners got pretty hip to the notion of using nukes against strictly military targets, but a couple of wrinkles emerged. First and foremost, using nukes on the battlefield was a reasonably straightforward logistical problem, the business of moving usable nukes deep into enemy territory was a bit more troublesome.

Back in the day, this was all done via bombers, but while very accurate (at least in nuke terms), were terribly slow and could be intercepted and shot down. To get past this particular problem, that wondrous German invention, the military ballistic missile, was harnessed to lob nukes across the world. The missiles could reach virtually anywhere on earth within about half an hour, they couldn’t be shot down, but they were horrifically inaccurate. Since they couldn’t be relied upon to get particularly close to their targets, the solution was to lob bigger warheads. So this drove the development of increasingly large warheads.

Meanwhile, as weaponeers were making larger warheads, other engineers were working on making ballistic missiles more accurate, so they could be used effectively against point targets, like other missile silos, without having to use enormous warheads. This had a couple of interesting implications in weapons design, one of which was the development of dial-a-yield warheads. Dial-a-yield allows planners to use one bomb if they want a great big explosion all the way down to a little tiny explosion (in the case of the B83 linked above, the bomb can produce a yield anywhere from about 20 kT up to 1200 kT) with very little complication. Why this is significant is that it is a pretty dramatic indication that planners decided that there was really such a thing as too big an explosion, even in a full-scale global thermonuclear war.

This is because things like fallout, nuclear winter, and sort of a general increasing interest in limiting unnecessary collateral damage (some studies indicated that even a “limited” nuclear war would result in as many as 20 million casualties on each side). This shift is also mirrored in thinking about tactical nuclear weapons. By the mid-sixties, things like the Special Atomic Demolition Munition, with a yield of 0.01, or 0.02-1 kilotons deployed. Along with this was a shift from deploying tactical nuclear weapons ubiquitously. All these things mark shifts in thinking associated with the usability of nuclear weapons.

While strategic nuclear weapons are explicitly intended not to be used, but only to provide a viable threat of use, tactical nuclear weapons are an entirely different beast (at least in the minds of American planners). The problems that folks discovered during the Vietnam era was that for tactical nuclear weapons to make sense they have to be imminently usable. What’s the point of building a huge nuclear arsenal if you can’t bring this force to bear against a bunch of pajama-clad insurgents running around in the bush? So planners spent a lot of time thinking about this kind of thing, which resulted in developments like the neutron bomb – a more “usable” tactical nuclear weapon.

Along came the end of the Cold War, which threw a bit of a wrench in planning activities. While many of the changes that occurred with the end of the Cold War were unquestionably good things, they had some odd consequences. For instance, the US dismantled it’s chemical weapons stockpiles – which is a good thing. But unfortunately, it also means that we lack an ability to retaliate in kind for the use of chemical weapons. Likewise, we used to have a program in place to destroy enemy satellites, but this has been cancelled. In both cases of chemical weapons and anti-satellite systems, we have sort of gotten around the loss of the ability to retaliate in kind by stating that we will respond to attacks of this sort as if they were nuclear attacks against the US.

But this brings about some of the same problems that planners ran into ages ago – tactical nuclear weapons are politically very difficult to use. As we’ve seen since the end of the Cold War, the US is facing an era in which not only will we be fighting against relatively small nations who can play the “bully” card to increase the political cost of using nukes, but these would-be adversaries that are most definitely seeking to exploit asymmetries to counter the massive conventional superiority of forces. So this makes it much more likely that these folks are going to do things that really require the use of nukes to counteract, but we’ll be in a significant bind because we don ‘t really have a terribly usable nuclear arsenal.

Among other things, despite the fact that we already very small nuclear weapons, they aren’t terribly usable, since they still will kick up a whole lot of fallout and whatnot. The second problem is that one of the strategies being aggressively pursued by China, Iran, North Korea and others, in response to the impressive airpower performance of the 1991 Gulf War, was the increasing tendency to place critical facilities underground (hardened, deeply buried targets – HDBT).

Which brings us to the buster bunkers. The deal is that while there are small nukes, they don’t have enough bang to do something like destroy a HDBT, and if a nuke large enough is used, it will kick up a lot of debris and release a lot of ionizing radition, and will hence generate a large political backlash.

So we end up with a gap in our deterrence. We could use a small nuke against something like a supply depot or a large formation in response to a chemical attack or whatever else we’ve said would be treated as a nuclear attack, but we don’t have something that can really be used “surgically”. Thus, if we want to be able to respond to something like a chemical attack, we have the option of doing something like nuking a whole bunch of soldiers in the field – which will generate some pretty unfavorable press and some really graphic images (think Highway of Death), but not the ability to actually tag anything particularly valuable, like a buried uranium enrichment plant.
Now the notion that it’s hypocritical for us to call for the US to call for counterproliferation while developing its own nukes is, in essence, completely and absolutely valid. And people who think that we should cancel the program because of this hypocrisy are absolutely missing the point.

If we have bunker-busting nukes, then we can open up our range of options for retaliation, and thus can extend deterrence to actually deter would be proliferators from acquiring or using WMD. If we don’t have them, then we simply don’t have a very good range of military options for responding to either the acquisition or use of WMD, short of regime change.

Now if we lived in the ideal world of a Kant, then it would make no sense whatsoever to pursue bunker-busters. That is also the world of strong international cooperation, and effective multilateralism. That’s also a worldview that took a mighty strong hit on a bright September morning some years ago. The relevance of 9/11 is that it’s a pretty strong indicator that we live in a fairly Hobbsean world, in which we can’t simply expect people to do what we want just because we set a good example.

So sad as it may seem, we live in a world such that if really could get away with not developing bunker-busters, we would live in a world in which we wouldn’t actually need the infernal things.

Launched by Bravo Romeo Delta at October 4, 2004 06:33 AM

Retaliatiory Launches

You know, the B61-11 has been in development for a while. I used to work for a nuclear safety guy who was invited to be on the review board for it back in 1995. It was tested as an airdrop from a B2 in 1998. (Let's see, this would have been the Clinton administration, so of course no objection from Kerry).

And gosh, I remember when Dial-a-Yield was a classified term.

Posted by: blaster at October 4, 2004 08:13 AM

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