During the second presidential debate on 30 September, Senator John Kerry stated that it didnt make sense for the United States to pursue research on nuclear bunker-busting weapons (or mini-nukes), and claimed that if he is elected, Im going to shut that program down. Why is this significant?
A little-known fact is that the United States already possesses a nuclear bunker-buster: the B61-11 nuclear gravity bomb. The B61 is a nuclear bomb that can be configured with yields ranging from 0.3 kilotons (kt) to 340 kt (the two lowest yields 0.3 kt and 1.5 kt fall into the mini-nuke category). The B61-11 variant has a hardened casing to provide earth-penetrating capability of 15-25 feet (4.6-7.8 metres). About fifty B61-11 bombs may have been deployed. So the real issue is whether the United States needs to develop and deploy more nuclear bunker-busters in the form of mini-nukes.
According to Kerry, if the United States moves forward with research on such weapons it would be sending mixed messages: Were telling other people, You cant have nuclear weapons, but were pursuing a new nuclear weapon that we might even contemplate using.
The purpose of having is using
But the problem with mini-nukes does not, as Kerry implies, involve a double standard whereby the United States can possess nuclear weapons while other countries cant. Rather, the illogic of mini-nukes is that the only logical purpose of having them is to use them pre-emptively to prevent rogue states from acquiring weapons of mass destruction (WMD).
Mini-nuke proponents argue that the combination of being able to place a warhead almost exactly on top of a target and the ability to penetrate a buried target before detonating means that a lower-yield weapon can be used to destroy the target. Because the weapon has a relatively small yield, it is less destructive and therefore more useable that is, the damage from the nuclear blast could be contained and thus inflict less collateral damage.
Furthermore, because mini-nukes would be more useable they would be more credible weapons and, therefore, a more effective deterrent. And if hardened and deeply-buried targets can be credibly held at risk, then rogue states could also be deterred from developing chemical, biological, or nuclear weapons in such facilities knowing that the United States could destroy them.
Such logic implicitly presumes that rogue states seek to acquire chemical, biological, or nuclear weapons strictly to directly threaten, challenge, or even attack the United States. Interestingly, some mini-nukes advocates (such as Keith Payne, a former deputy assistant secretary of defense in the current Bush administration) acknowledge that rogues states have other reasons for acquiring WMD, such as political and military purposes against regional foes. Yet they fail to grasp the logical implications of their own correct conclusion.
It is true that rogue states have their reasons for wanting nuclear weapons. A primary one is to deter US military action, including pre-emptive regime change. In other words, rogue states are acting in their perceived self-interest for purposes of survival. But if acquiring nuclear weapons is seen by leaders of rogue states as the only possible way to deter the United States and ensure the regimes continued survival, then US mini-nukes will have little effect in deterring rogue states from seeking to acquire such weapons. That is, rogue-state leaders will conclude that whatever the risk, it is a chance they must take to have any hope of staving off US-led regime change.
And if United States policy is absolutely to prevent rogue states from acquiring WMD, failure to use mini-nukes against even one rogue state pursuing WMD would undermine the claimed deterrent effect of mini-nukes on other rogue states. If the US did not use mini-nukes for their stated purpose deterring rogue states from acquiring WMD then they would be a hollow threat.
The remorselessly logical conclusion is that the only logical purpose of having mini-nukes is to use them pre-emptively, if necessary.
Neither deterrence nor usability
A very practical problem here intrudes, one illustrated by the experience of the Iraq war: any battlefield use of mini-nukes would be highly problematic. If the Bush administration had mini-nukes (which it wants), it might have used them in a pre-emptive fashion on the slim pretext that Saddam Husseins (in the event, non-existent) WMD arsenal might possibly be given to (in the event, non-aligned) al-Qaida terrorists.
The Iraq war also calls into question the likely effects of mini-nukes on the ground. The existing B61-11 nuclear bunker-buster can be configured with yields low enough to be categorised as a mini-nuke. Outfitted with global positioning system (GPS) guidance, it has the potential to be used as a precise, earth-penetrating low-yield nuclear weapon against high-value underground targets.
On at least two occasions US intelligence indicated that Saddam Hussein was thought to be in underground bunkers that were subsequently attacked with precision conventional weapons. If Hussein was arguably the highest-value target in Iraq during the war, then a good case could be made for using a nuclear weapon like the B61-11 to ensure the completion of a key part of the overall US war strategy: killing him and decapitating the regime.
But the fact that the United States chose not to use the B61-11 during the Iraq war suggests one of two things: either even a relatively low-yield nuclear weapon detonated underground would produce too much damage, particularly if located in a densely-populated urban area like Baghdad; or there is a real stigma or aversion to US first use of nuclear weapons, even against adversaries who cannot retaliate in kind.
The fundamental reality is that mini-nukes are not likely to deter countries from pursuing WMD programmes and are equally unlikely to be used to prevent countries from acquiring WMD. So there is little logic in conducting research to develop mini-nukes. Indeed, it is technological advances in conventional weapons capacity for precision-delivery and depth-penetration that has made using mini-nukes to destroy hitherto indestructible underground targets a tantalising possibility.
But the original impetus for developing such precision conventional weapons should be recalled: it was to be able to hold at risk targets that at that time could only be destroyed by nuclear weapons. It made sense then to find non-nuclear ways to destroy targets. It makes no sense now to invent new nuclear weapons to destroy the same kind of targets.
