Nuclear counter-terror effort evolves

The United States and Russia on June 1 agreed to accelerate a joint program to install radioactivity detection systems along Russia’s borders by 2011.

Washington hopes that improving its ability to identify the source of a nuclear explosion, known as nuclear forensics, may compel other states to increase the security of their fissile materials. It is part of an evolving policy to deter nuclear terrorism — which also involves deliberate ambiguity about the nature of the U.S. response against any states that
intentionally or unintentionally allow terrorists to acquire nuclear material.

Since the detonation of the first Soviet nuclear device in 1949, Washington has relied on deterrence to protect itself against a nuclear strike. The strategy rested on the explicit threat that the U.S. response would inflict unacceptable losses on an attacker — obviating any possible benefits to the aggressor — and the assumption that the attacker would be easily identifiable. However, following the terrorist attacks of Sept. 11, 2001, Washington became concerned that a terrorist group could smuggle a nuclear device into the United States and detonate it in place. This would make “attribution” of the attacker extremely difficult, undermining deterrence and the ability to respond.

Strategic response.

To address the new threat, the United States is working towards a new strategy of “extended deterrence” and “strategic ambiguity.” The aim is to deter states from assisting nuclear terrorism by identifying the source of the bomb material after use. However, tracing an attack back to its source would rely on accurate intelligence and the budding science of “nuclear forensics.” Given international concerns about U.S. intelligence capabilities following the invasion of Iraq, there is increasing interest in beefing up the technical assets available for nuclear attribution.

Nuclear forensics.

Nuclear weapons must be made from one of two substances — highly enriched uranium or plutonium. These materials have unique isotopic compositions, depending on how and where they are produced, which give the end product a unique nuclear isotopic composition or “nuclear fingerprint.” In the case of plutonium production, such distinctions come as a result of how reactors are designed and operated, and how plutonium is extracted from spent fuel. For uranium, the isotopes are determined largely by the place where the uranium is mined and how and where it is enriched.

If the United States could build a comprehensive database of nuclear materials from all sources in the world, it could have some confidence that any nuclear attack would yield enough clues to determine the source of the nuclear materials used in the bomb. Even if Washington did not have intelligence on all nuclear reactors and all uranium mines, the information that it did have might rule out possible sources of an attack. While not ideal, this would allow other intelligence resources to concentrate on those remaining suspect countries.

Securing international cooperation.

 It is highly unlikely that all states will provide the necessary samples to the United States, or the International Atomic Energy Agency (IAEA), to build such a nuclear database. However, even an incomplete library could improve international security, because:

•requesting samples would be a confidence-building measure; and

•gauging the degree of state cooperation could help focus international pressure on those states that refused to help prevent and deter nuclear terrorism.

States could possibly try to misuse the collection process and provide samples that might not reflect the true nature of their nuclear materials. Therefore, careful verification procedures would be essential. This would be complicated, but is within the ability of the IAEA to verify samples through inspections or site visits.

Security incentives.

 Another potential benefit of a nuclear materials database collection program is that if states believe that any breach of their nuclear security could potentially make them the victim of a retaliatory strike, they might do more to ensure their materials are not stolen or diverted. By offering financial assistance for stepped-up nuclear security programs at the same time that requests are made for samples, Washington and its partners might improve nuclear security in general.

Covert options.

The United States and other national forensic efforts would not need to rely only on voluntary samples. Intelligence and special operations teams could, over time, collect samples from various sites that might be off-limits through normal diplomatic avenues.

Policy challenges.

 Given current technology, Washington and other advanced nuclear powers can develop the capability to trace materials used in a terrorist nuclear explosion back to the source of the material. However, relying exclusively on nuclear forensics to reinforce a strategy of deterrence would carry risks:

•Imperfect knowledge. There are no guarantees that samples collected in the wake of an attack will match national or international source databases.

•Fallible analysis. There is always a chance of flawed technical analysis that could falsely identify a state as the source of a nuclear attack.

•Danger of misattribution. Even if the system works well and correctly, an over-reliance on forensics might be dangerous. If nuclear material is stolen, forensic analysis could identify a country as the source of the original nuclear material without providing insight into whether or not the state was otherwise involved. Indeed, a terrorist group could intentionally seek to trigger a massive U.S. strike against an uninvolved third party.

Credible retaliatory threat.

Washington believes that to deter states from abetting nuclear terrorism, nuclear forensics would need to underpin a policy where:

•the threat of retaliation is sufficiently credible to ensure that states secure their stocks of nuclear material against theft; and

•any state that might consider passing nuclear materials to a terrorist group would be convinced that they would be identified.

However, ensuring that the U.S. threat of massive retaliation is credible will be challenging. During the Cold War, Washington maintained that it would launch a nuclear reprisal capable of destroying at least 50 percent of the Soviet Union’s population and 75 percent of its industrial base in response to a Soviet nuclear strike. Yet even at the height of U.S.-Soviet tensions, there were doubts about the credibility of the threat of massive retaliation.

In the current global political environment, it is doubtful that the international community automatically assumes, for example, that a nuclear attack against Boston would result in a massive U.S. nuclear strike against Tehran or Pyongyang — which might result in hundreds of thousands, or even millions, of casualties. Indeed, the threat of an overwhelming conventional response, which would overthrow the regime in question, might be more credible.

Strategic ambiguity.

The realities of international politics suggest that deliberately preserving strategic ambiguity about the nature of U.S. retaliation in the event of nuclear terrorism, and the precise technical capability of its nuclear forensic system, may be the most effective course. International awareness that Washington had developed a serious nuclear forensic capability could influence the decision-making process of state terrorist sponsors. Therefore, the administration is currently debating whether to make a public announcement that it would hold all states “fully responsible” if their nuclear material ends up in a terrorist weapon. The nature of the term, and the precise U.S. response to nuclear terrorism, would be left deliberately vague.

Oxford Analytica is an international consulting firm providing strategic analysis on world events for business and government leaders. See .