Nelson replies: Jeffrey Marque properly highlights the thoughtful policy and technical analysis by Michael May. A former director of Lawrence Livermore National Laboratory, May concludes, as I do, that “nuclear weapons don’t help much with the kinds of missions the US prepares for, including … digging out deep underground facilities that might contain bio-warfare agents.” 1  

I agree with Bryan L. Fearey, Paul C. White, John St. Ledger, and John D. Immele that a nuclear earthpenetrator could collapse a bunker of intermediate depth using a lower-yield warhead than would be required from a surface burst. However, these “reduced collateral damage” nuclear weapons would still result in tens of thousands of casualties if used in an urban environment. 2 And high-yield weapons, with their extreme fallout, would be necessary to destroy bunkers buried deeper than a few hundred meters. The alternative would be to use conventional weapons to collapse the entrances, exits, and ventilation shafts to the underground facility.

A popular scenario in which nuclear use might seem justified is that of a tyrant threatening to use chemical and biological weapons stored in an underground bunker. However, Fearey and coauthors mischaracterize my article as implying that a nuclear earth-penetrator would be an effective weapon to sterilize these buried agents. For that to be the case, the geometry of the shallow bunker must be known precisely, and the weapon must be guided to penetrate the very underground room where the enemy has conveniently placed all chem-bio stocks. A near miss would more likely spread active chemical or biological agents into the environment rather than destroy them. 3 The intelligence community’s identification of “590 suspect chemical and biological weapon sites” 4 just before the recent war in Iraq might give one pause.

At best, proposed bunker-busting weapons would add only marginal improvements to current US nuclear capabilities. Yet building such weapons would reverse the decadelong US commitment—initiated in 1992 by President George H. W. Bush and extended by President Bill Clinton—to halting further development of new nuclear weapons and to a moratorium on nuclear testing. Similar commitments by all five of the nuclear powers were essential to gain support for the 1995 extension of the Nuclear Nonproliferation Treaty. Breaking those commitments could threaten the nuclear nonproliferation regime.

But even if the US ignores its international commitments, it is in our security interest to continue to deemphasize the utility of nuclear weapons. Again, quoting May:

Given the overwhelming US conventional advantage and the relative invulnerability of the US to all but nuclear weapons, the US nuclear posture should aim at minimizing the chances of nuclear weapons spread rather than seeking marginal gains with tactical nuclear weapons. Nuclear weapons are equalizers. Why bring them back into the forefront of regional problems, whether in the Middle East or anywhere else?

2.
3.
R. W.
Nelson
,
Science & Global Security
(in press). Draft available at http://www.princeton.edu/~rnelson/papers/agent_defeat.pdf.
4.
Cited by Senator Carl Levin of Michigan, speaking for the National Defense Authorization Act for Fiscal Year 2004, on 21 May 2003, S.1050, 108th Congress, 1st sess., Congressional Record 149, S6800.