Nuclear Proliferation

Matthew Bunn
Senior Research Associate, Project on Managing the Atom, Harvard University
Wednesday, September 26, 2007; 12:00 PM

Matthew Bunn of Harvard's Project on Managing the Atom discussed the findings of Securing the Bomb 2007, a report on the security of nuclear weapons and materials around the world, at Wednesday, Sept. 26 at noon ET.

Thwarting Nuclear Terrorists: More to Be Done | FAQ | Quiz (Post, Sept. 26)

The transcript follows.


Washington: What is your take on the missiles recently flown from Minot down to Louisiana? How can we possibly lecture other countries on nuclear security?

Matthew Bunn: This incident clearly reflected a major breakdown in security procedures. Clearly an in-depth investigation of how this happened, and modified procedures to ensure that it can never happen again, are needed. However, the nuclear weapons were never out of the control of the U.S. military, and were never at any very substantial risk of theft.

I have long believed that we will get farther in cooperating with other countries on nuclear security if we admit that we are not perfect either, acknowledge problems that we have had, and discuss ways that we have found of addressing those kinds of problems -- rather than taking the attitude that we know exactly what should be done, and other countries should just do as we say.


Boston: Any opinions about those mythical backpack nukes that some Russian leaders have said have gone missing? Thanks very much for taking questions.

Matthew Bunn: It is clear that both the United States and the Soviet Union did produce nuclear weapons designed to be carried by one or two people. In the 1990s, Gen. Alexander Lebed, then Russian President Boris Yeltsin's national security adviser, claimed that a substantial number of what came to be called "suitcase bombs" were missing. The Russian Ministry of Defense and everyone responsible for nuclear weapons in Russia denied this was the case. Eventually enough information was released that I think it is very likely that these nuclear weapons were never missing in the first place. To date, there is no convincing evidence that any actual nuclear bomb has ever been stolen or fallen into hostile hands. There's a good account of this episode that Nikolai Sokov and others at Monterey published a few years back.


Boston: I've at least skimmed several years of your report. This one has more of a focus on the need for the sustainability of nuclear security programs, and the adoption of a "security culture" at nuclear weapons and nuclear materials sites. Given the recent B-52 incident (where nuclear weapons were mistakenly attached to cruise missiles, and flown across the United States) and persistent security lapses at Department of Energy labs, there doesn't seem to be much of a security culture at home. What can the U.S. practically do to convince nuclear security operators and militaries in other countries to adopt a "security culture"?

Matthew Bunn: As you say, building strong security cultures has proven to be a hard problem for the U.S. government even in the United States, where it can set the rules, pay the costs, and choose the people in charge. (The head of the National Nuclear Security Administration was fired earlier this year, in essence, for not being able to change the security culture that kept leading to incidents at Los Alamos.) Helping other countries change security cultures is an even tougher problem -- one of the hardest public policy problems I have ever attempted to grapple with.

But it is absolutely essential. As Eugene Habiger, former commander of U.S. strategic forces and former security czar at DOE, once put it: "good security is 20% equipment and 80% culture."

The most important key to building a strong security culture is convincing all security-relevant staff that the threat is real, and the security rules are not just inconveniences that don't mean much. In the report, I outline a wide range of steps that should be taken to make that case -- briefings on the reality of the nuclear terrorism threat, nuclear terrorism exercises and simulations, realistic tests of the performance of security systems in stopping outsider and insider thieves, shared databases of nuclear security-related incidents (to the extent possible within classification rules), and more.


Potomac, Md.: Iran has neither plutonium nor enriched uranium according to your map, yet it is the focus of concern of Bush administration. Do you think this is a well-placed priority? Or should the Bush administration be focusing on nonproliferation generally through the U.N. and other diplomatic efforts?

Matthew Bunn: Iran does not currently pose a major danger of potential bomb materials being stolen and falling into terrorist hands -- the focus of the map.

Iran, however, is building thousands of uranium enrichment centrifuges. Those can make low-enriched fuel for civilian nuclear reactors, or highly enriched uranium for bombs. If successful, this will put Iran right at the edge of a nuclear weapons capability while staying within the Nonproliferation Treaty. Given Iran's record, including its 18 years of violating its safeguards obligations with the IAEA, the United States and many other nations are right to be concerned about Iran's enrichment program. We need to put together an international package of carrots and sticks that is large enough and credible enough to convince the Iranian government that it is in their interest to agree to an arrangement that will leave as large and verifiable a gap as possible between their permitted capability and nuclear weapons.


Waltham, Mass.: How much, if any, of the missing nuclear materials has been accounted for, and do the existing missing materials continue to pose a threat?

Matthew Bunn: With only one exception, the cases of nuclear theft that we know about we know about because the material was seized and recovered. (The exception is a small amount of highly enriched uranium that appears to have been removed from a research facility in Sukhumi during the Georgian civil war.) But how many cases are there that we don't know about, because the smugglers never got caught, and how big were they? No one knows the answer to that fundamental question -- though it's my belief that already-stolen material poses only a modest part of the total risk of nuclear terrorism.

Unfortunately, the question of how much material is "unaccounted for" is itself impossible to answer. During the Cold War, in both the United States and the Soviet Union, the emphasis was on producing huge stockpiles of plutonium and HEU, not on accounting for every kilogram. In the United States, as a result, tons of plutonium and HEU are officially unaccounted for. There is no evidence any of this was stolen -- it was largely plated out on pipes in factories, flushed down drains with the waste, and the like. Russia has not done a comparable accounting of how much it produced and where it all is now, but it is clear from what we know about the Soviet-era accounting system that the total amounts that cannot be accounted for there will be much higher. No one will ever be able to be sure that some of that material was not stolen.


Williamsburg, Va.: Suppose a nuclear device is detonated in an American city. Is it possible to determine the origin of the fissile material, by looking at various isotopic impurities? How long would it take to make this determination? This is obviously relevant for deterrence.

Matthew Bunn: The science of attempting to make such attributions is known as "nuclear forensics." U.S. scientific programs in this area are now being revitalized after some years of minimal funding, though more funding is still needed. Unfortunately, the physics of the problem suggests that there will be substantial uncertainties in trying to say "this definitely came from country X." As just one example, the United States itself shipped HEU to some 40 countries. So we might be able to determine that the bomb came from HEU enriched in the United States, but there might be several possibilities as to the country it was stolen from. It is likely to be easier to rule out countries than to definitely identify one particular country by nuclear forensics alone.

But nuclear forensics doesn't have to work alone -- it will be one tool used with all the other tools of intelligence available. The 9/11 attacks involved no radioactive isotopes to look at, but it did not take long for us to establish who carried out those attacks, and a great deal about how they organized the plot.

In the report, I argue for increased investment in nuclear forensics, and make the case that the United States should publicly declare that any terrorist nuclear attack that comes from material consciously provided by a state will be considered as an attack by that state, and responded to accordingly.


Boston: Don't we have a program to stop and inspect ships we suspect are being used to illegally transfer nuclear processing materials? Where was the breakdown on the North Korean ships that were suspected of bringing nuclear equipment to Syria? Did the Israelis figure it out after the ships had unloaded? If before, did they not share that intel with us? If they did share it with us, did we not think the intel was strong enough? Did we and our allies on the program not have naval assets in the area? Or, more broadly, did we not want to act ourselves and jeopardize our ongoing negotiations with the North Koreans (and left it for the Israelis to take care of it for us)?

Matthew Bunn: Publicly available information about what, if anything, is going on between North Korea and Syria on nuclear matters remains murky. The best reporting I've seen on what Israel struck suggests that it was actually missiles and missile equipment, rather than nuclear equipment.

There is a new effort called the Proliferation Security Initiative, whose purpose is to stop shipments of missiles, nuclear, chemical, or biological weapons, and related technologies. But under international law on the freedom of the seas (whose preservation is essential to U.S. national security in other areas) you can't just stop and seize ships on the high seas. So what PSI has done is gotten agreements from many countries that shipments that pass through their waters or airspace can be stopped if there's reason to believe they are related to these technologies, and from countries whose flags are used for most of international shipping that ships flying their flags can also be stopped. Intelligence, of course, is also a key problem -- when these shipments are made, there are usually intense efforts to keep them secret, so it requires an intelligence break to know that a particular ship is one that should be stopped.


London: It seems to me that the way that al-Qaeda now operates is that, excluding the Waziristan area of Pakistan -- which increasingly is being targeted by Pakistan troops -- all cells only are affiliated loosely to the organization. I know the argument goes that terrorists only have to be successful once, and that getting enough fissile material to make a simple gun-type nuclear weapons would not be too difficult but -- given the recent trend of terrorist incidents in the West -- terrorists seem to show a lack of understanding in attempting to build even the simplest kind of bombs, let alone a device that whichever way you look at it is more complicated than other more traditional devices. As such, is there not a strong argument that this report only is increasing terror among the general population -- something that al-Qaeda and other organizations are aiming to achieve anyway? Many thanks.

Matthew Bunn: As I describe in the report, getting nuclear material and making a nuclear bomb from it would be perhaps the most difficult and complex operation that any terrorist group has ever accomplished. But the risk is nevertheless very real. The size of the operation needed to put together a crude nuclear bomb might be quite modest -- small enough so that it might not be detected until it was too late. U.S. intelligence is convinced that the reconstituted al Qaeda central command in the mountains of Pakistan remains capable of organizing complex, high-casualty operations. So while it is true that several of the incidents we know about related to al Qaeda nuclear or radiological activities are quite unsophisticated, we still have to worry about activities we DON'T know about -- or capabilities they may be able to pull together in the future.

Even if the probability of a terrorist nuclear attack over the next ten years were only 1% -- which I don't believe -- given the horrifying consequences, that would be enough to motivate major efforts to reduce the risk.

The purpose of this report is to provide a realistic assessment of the risk and the progress made to date in reducing it, and to outline a plan for dramatically reducing the risk.


Reading, Pa.: Sir: In your opinion, what is the likelihood that components of a nuclear device of some kind already have found their way through our borders?

Matthew Bunn: I think this likelihood is very small. If I were a terrorist trying to set off a nuclear bomb in the United States, I would be desperately worried that something would go wrong and I would be caught, so I would set it off as fast as I could, rather than leaving the materials lying around in the United States for a prolonged period.

The case I make in the report is that there is still time for focused action to reduce the danger of nuclear terrorism to a small fraction of what it is today -- and thereby greatly improve U.S. and world security.


Tappahannock, Va.: You said that we need to convince people that the threat is real so that appropriate actions are taken. Is the administration taking adequate steps to do that? What more can be done?

Matthew Bunn: To their credit, the Bush administration and Congress have expanded and accelerated U.S. programs to lock down nuclear stockpiles around the world.

But much more remains to be done, as outlined in detail in Securing the Bomb 2007. In particular, more needs to be done to convince political leaders and nuclear managers in foreign countries that nuclear terrorism is a real and urgent threat worthy of investing THEIR time and resources in addressing. I outline a series of steps that should be taken, including: joint briefings on the nuclear terrorism threat at upcoming bilateral summits; nuclear terrorism exercises and simulations; shared databases of nuclear security incidents; realistic tests of the ability of outside attacker or inside conspirators to overcome security systems; and more.

As just one example of the need for expanded awareness of the threats, in 2003 a Russian court case revealed that a Russian businessman had been offering $750,000 for stolen weapon-grade plutonium for sale to a foreign client, and had made contact with people in the closed city of Sarov (Russia's Los Alamos) to try to close such a deal. No one I have spoken to from other Russian nuclear sites has ever heard of this case. Surely the fact that some people are willing to offer that kind of money for stolen bomb material is a relevant fact that nuclear security managers should be aware of!


Washington: Everyone is saying that the six nuclear cruise missiles that were mounted on a bomber wing and flown through the Midwest in August were never a danger. I believe that is true because the government says so, but what further accidental missteps would have been needed for one to be activated and dropped on a Midwest city? Were that to happen in the future, would the reaction be to admit an accident, or to blame terrorists?

Matthew Bunn: This incident did represent a very grave breakdown in security procedures, but as you say there was never any significant risk of a bomb being dropped on a U.S. city and going off. Nuclear bombs of this type are equipped with a series of safety switches that prevent them from detonating unless very specific actions are taken to arm them and, in effect, tell them to detonate. In addition, many nuclear weapons (though not strategic weapons on ballistic missiles) are equipped with built-in electronic locks designed to prevent them from detonating unless someone inserts the correct code.


Freising, Germany: Supposing that a terrorist group managed to gradually obtain enough highly enriched uranium to create a crude atomic bomb. What skill sets would the bombmakers have to have in order to create the bomb? In a small makeshift bomb laboratory, would radiation exposure eventually kill those who would try to build an atomic bomb?

Matthew Bunn: Unfortunately, by far the hardest part of making a bomb is getting hold of the nuclear material. Repeated studies by the U.S. government and others have concluded that it is plausible that a technically sophisticated and reasonably well-financed terrorist group could make a crude nuclear bomb. They would need people skilled in several technical areas, including physics, machining, and explosives, among others; they would need machine-shop-type facilities; it would be helpful to be able to set off some explosives to test various approaches without drawing too much attention. They would not necessarily require either access to classified information or large fixed facilities, and the equipment needed could be purchased commercially without drawing special attention.

Moreover, HEU is not very radioactive, so if HEU was their bomb material, they would face little danger of being killed by the radiation unless they had an accident in which a nuclear chain reaction began (a so-called criticality accident). (Plutonium is more radioactive, and would probably require them to use at least a crude glove box arrangement to limit their exposure.) In the early days of the Chinese nuclear weapons program, for example, HEU bomb components were reportedly machined by hand, with no special precautions.


Washington: If the likelihood that terrorists could make a nuclear weapon is really so credible, why isn't more being done?

Matthew Bunn: There are dozens of programs in place addressing pieces of the problem of reducing the risk of nuclear terrorism. They are making genuine progress -- many of the world's most dangerous stockpiles are demonstrably more secure today than they were fifteen years ago.

But as detailed in the report, there is still much more that remains to be done. The reasons why some of these actions are not yet being taken are complex. There is a widespread belief that everything that could be done is being done. That is wrong, as demonstrated by the detailed recommendations in Securing the Bomb 2007. Many officials in many countries simply do not believe the threat is especially urgent; complacency is a huge barrier to rapid action. There are a wide range of bureaucratic and political obstacles that must be addressed and overcome.

In short, the U.S. government IS treating this as an important problem -- but they are not yet treating it as what President Bush says it is, the number one threat to U.S. national security. As President Bush has said, the nations of the world need to do "everything in our power" to keep nuclear weapons and the materials needed to make them out of terrorist hands. We aren't there yet.


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