On 31 March President Obama convened in Washington, DC, the fourth and last Nuclear Security Summit of his presidency. The goal of the summits has been to secure nuclear materials against diversion and unauthorized use. And indeed, the summits have encouraged countries to make significant progress toward that goal. Why, then, do so many reports on this summit emphasize the fear of nuclear terrorism rather than the steps that are being taken to prevent it?
Nuclear terrorism—using radioactive materials for terrorist purposes—brings to mind a nuclear weapon being detonated over a large city and creating a mushroom cloud. Another possibility is a dirty bomb, which combines a conventional explosive with radioactive material, that would spread radioactive dust. The difference between the two is not clear in many people’s minds. The foremost danger of a dirty bomb lies in the panic it would cause. And confusing messages about nuclear terrorism are likely to stoke that panic.
Nuclear security is unglamorous. It is mostly paperwork, bar codes, locked vaults, and the logistics of safe transport. But securing the 1800 tons of fissile materials around the world means no fission or dirty bombs for terrorists. When the Soviet Union broke up, nuclear experts across the globe were concerned that its nuclear materials, and perhaps even its nuclear weapons, would be scattered and make their way into terrorist hands. Thanks to efforts such as the Nunn–Lugar Cooperative Threat Reduction Program, that hasn’t happened.
Although uranium and plutonium can be used in nuclear weapons, they are not the best materials for a dirty bomb; in fact, uranium would be quite ineffective. More useful would be large industrial sources, such as cobalt-60 or cesium-137, that are used in hospitals or as remote power sources.
Radioactive sources were ignored as a potential danger until the first decade of this century. I saw it firsthand. After a few trips to Estonia to help with the cleanup of a former Soviet uranium yellowcake plant, I found that the Soviets had left smaller radioactive sources scattered carelessly about with limited security. A number of people worked to raise government awareness of those hazards, and programs were put in place to retrieve and store the sources safely.
There hasn’t been a dirty bomb attack to date.
President Obama began the biennial Nuclear Security Summit in 2010 to add glamour to the unglamorous. Heads of state in attendance have presented their achievements and made new proposals. And they have delivered on their promises. Nuclear materials are becoming more secure. During the recent summit, for example, an amendment to the Convention on the Physical Protection of Nuclear Material came into force that requires increased security.
Additionally, the fuel for research reactors is being converted from highly enriched uranium (HEU) to low-enriched uranium; each year the number of reactors that use HEU decreases. Many hospitals that provide cancer therapy no longer are using nuclear reactors for radioisotope sources of gamma rays but instead are using accelerators, which produce gamma rays from electricity. The biggest vulnerabilities in Russia and other countries of the former Soviet Union have been addressed: Accounting systems now track materials, and physical security has been tightened.
A poor message?
But the narrative expressed in press releases by governments and associated organizations, particularly nongovernmental organizations (NGOs), can be confusing. NGOs have seized on fear as a way to get public attention for their cause.
Fear is a poor motivator, and repetition of threats desensitizes people to actual threats. The general public can do little about poorly monitored nuclear material and radioactive sources, but the message being disseminated is that people should be afraid of loose nukes. That fear is compounded by the fact that although attendees at the summit discussed a breadth of topics, they gave no indication of which threat poses the greatest danger. This list, from the White House, exemplifies that problem: worthy achievements, some of them as dull as I’ve noted, spelled out in bureaucratese. The sensational or provocative topics, however, rise to the top.
Print and online news outlets have produced poorly sourced stories about how the Brussels and Paris bombers might have been looking for materials for a dirty bomb or worse. Op-eds have proclaimed that the threat of nuclear terrorism is “bigger than you think.” The stories are hypothetical enough that they can be disavowed as possibilities only. But those possibilities are featured in the stories in a way that suggests a much higher probability.
The truth is that most of the fissile material in nuclear weapons, research reactors, and the supply chain for medical isotopes has been guarded for a long time, and more has come under guard since the summits began. Terrorists, by and large, go for the simplest approach to cause the greatest damage. Neither fission nor dirty bombs are simple.
To obtain a nuclear weapon, terrorists would have to get past armed security, take the weapon out of its vault, carry it past the response forces that will have been alerted, and figure out how to get past the permissive action links that allow the bomb to be detonated. Or, in the case of a reactor or other source of fissile material, terrorists would have to get past security (usually armed), take the material out of its vault or reactor, work it into the form for a bomb, and supply all the other explosives, detonators, and electronics needed. Getting through the permissive action links or making a bomb from stolen material would require days or weeks, during which time an unprecedented manhunt would be in progress.
But what about terrorists getting the materials through nuclear smuggling? All public reports of nuclear smuggling so far have been attempted sales of small amounts of materials. No buyers beyond the law enforcement sting seem to be available (see Physics Today, July 2001, page 29).
What does occur fairly regularly is the mishandling of radioactive sources. Over the past few years in Mexico, several sources were stolen when thieves either inadvertently made off with a vehicle carrying the material or took a radioactive container from a truck. Speculation in the news focused on dirty bombs. But the thieves simply dumped the sources. Again, the worst fears were not realized.
Every summit decreases the danger by securing the few materials sought by terrorists. Those efforts should continue. Inflating improbable events to promote fear is a disservice that makes it more likely that people will panic if a terrorist attack uses nuclear materials. The focus of the Nuclear Security Summit is problem solving. That should be the public message too.
This post first appeared in Physics Today. The photo is from there.