Summer 2016 Bulletin

The Comprehensive Nuclear-Test-Ban Treaty at 20

Global Nuclear Future

On May 19, 2016, Lassina Zerbo (Executive Secretary, Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization), Rose E. Gottemoeller (Under Secretary for Arms Control and International Security, U.S. Department of State), Siegfried Hecker (Senior Fellow, Freeman Spogli Institute for International Studies and the Center for International Security and Cooperation; Research Professor of Management Science and Engineering, Stanford University), and Robert Rosner (William E. Wrather Distinguished Service Professor in the Departments of Astronomy & Astrophysics and Physics, and the Enrico Fermi Institute and the Harris School of Public Policy Studies, University of Chicago) participated in a discussion on the prospects for ratifying the Comprehensive Nuclear-Test-Ban Treaty and the challenges presented by nuclear testing. Arun Rath (Correspondent, NPR and WGBH) moderated the discussion. The program, which served as the 2016 Distinguished Morton L. Mandel Annual Public Lecture and the 2039th Stated Meeting, was live streamed to Fellows and guests gathered in Palo Alto, Chicago, and Washington, D.C. The following is an edited transcript of the presentations.

Lassina Zerbo

Lassina Zerbo

Lassina Zerbo is Executive Secretary of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO).

The first time I toured the Academy, Francesca Giovannini, who directs the Academy’s projects in global security and international affairs, said to me, “You will be having lunch with Jonathan Fanton, our president, and you have to convince him that the Comprehensive Nuclear-Test-Ban Treaty is an important matter that needs to be discussed here.”

After that lunch, Jonathan Fanton made me a promise and that promise gave me hope. Keeping the promise has built trust between the CTBTO (Comprehensive Nuclear-Test-Ban Treaty Organization) and the Academy. Three to four hundred people in Vienna are working, day in and day out, for this treaty, which opened for signatures twenty years ago and has yet to enter into force. The importance of moving forward with the treaty is undiminished and still urgent.

For the past twenty years the CTBTO has been busy laying the groundwork for the effective implementation of the treaty and preparing for its entering into force. But where are we? After twenty years, we are still considered a preparatory commission, even though nothing about the work we do is preparatory.

We are fighting to ensure the treaty enters into force. My good friend Rose Gottemoeller is sparing no effort in making sure the educational framework in the United States is well on the way to prepare for the ratification of the CTBT (Comprehensive Nuclear-Test-Ban Treaty), a ratification that President Obama has made a priority.

How is the CTBT contributing to the international community? Many states, including the United States, have their own technical means of detection, but we bring legitimacy to the potential detection that could come from any state or from the international organizational framework we have in Vienna.

However, we have a risk that if the treaty doesn’t enter into force, this cooperation framework we have built might fall apart. If we have one, two, three, four, or five countries that refuse to send data to Vienna, then that is it. You can forget about the international monitoring system as a whole, and we don’t want that.

So that is why we are here, and that is why we fight to show that we are ready in Vienna. The international monitoring system is ready. The verification regime of the CTBT is ready.

But we need your leadership too – you, the members of the Academy, as well as our youth, our future leaders, who are really the leaders of today because they lead the world of social media. I would like you to help us by using the leadership you have on social media to push for this treaty and help us build the public awareness that is needed for the CTBT to enter into force.

I feel we missed some opportunities with Iran. Even though I understand why the CTBT was not brought to the discussion, I think it was a missed opportunity both in Iran and in Syria, and I think we should not miss any further opportunities to make a case for the CTBT. But the Iran deal is offering something in the Middle East, where the CTBT can be used as background to create the conditions necessary for a WMD-free zone in that region.

In India and Pakistan we need to work with the younger generation and see what we can do together. With North Korea, I am an advocate of keeping dialogue open, even if we have to be very firm with them. We have to keep in mind that the more we let them do tests, the more opportunity we give them to improve what they have already. Ultimately, we need the CTBT for international peace and stability.

Rose E. Gottemoeller

Rose E. Gottemoeller

Rose E. Gottemoeller is Under Secretary for Arms Control and International Security at the U.S. Department of State.

I would like to thank the Academy for the invitation to speak today. Jonathan Fanton, the Academy’s president, said something earlier: “We don’t have the luxury to surrender to skepticism.” That has been my watchword in this process over the past several years.

In the United States we have a lot of work to do to remind the American public of the enormous value that the CTBT has for U.S. national security.

Over the past 71 years, more than two thousand nuclear explosive tests took place around the world. Since 2000, only North Korea has tested, however, so I consider it somewhat of a victory that the voluntary moratorium that was put in place in the 1990s on explosive nuclear testing is so far holding pretty well.

But we cannot count on that. There are pressures on the moratorium at every turn. Recently I was in Pakistan and India. They recommitted to the moratorium, but we know from watching the development of their nuclear arsenals that they are itching to test. They would really like to develop new nuclear weapons capabilities, so we need to get to the point where we have a legally enforced treaty, both to strengthen the norm and to give us a way to monitor and verify compliance with the treaty. So this treaty is very important for U.S. national security.

The aboveground tests conducted last century created a wealth of problems for health around the world. Here in the United States I remember very well when I was a child how radioactive and cancer-causing particles such as strontium-90 got into the milk supply, into the food supply, and led to a lot of concern among parents about explosive nuclear testing in the atmosphere.

That was the first push. Then the Cuban Missile Crisis occurred, and that gave President Kennedy the opportunity to step forward and say, “We need to begin the process of banning nuclear weapons.” In just one year he was able to take a significant step in that direction, negotiating and bringing into force a limited test ban treaty that banned the atmospheric testing explosions that were causing the problems with the food supply.

That happened in 1963. Years later we moved forward to a threshold test ban treaty in the early 1990s, placing additional constraints on nuclear testing. But only in the mid-1990s were we able to negotiate a verifiable comprehensive test ban treaty banning all nuclear explosive testing.

The United States did sign the CTBT. In fact, President Clinton was the first to sign the treaty. But we have not been able to ratify it. The Senate, in 1999, failed to give its advice and consent to ratification. At that time, the senators asked two questions. First, they asked, “How do we know this thing can be verified? How do we know it can be properly monitored? You have promised us an international monitoring system, but it hasn’t been built yet. How do we know it is going to be built? How do we know the whole world will join in putting these sites on their territory – seismic sites, radioactive-nuclide sensing sites, infrasound sites? How do we know the world will join in this effort?”

Second, they asked how we would maintain our own stockpile without explosive nuclear testing for as long as nuclear weapons continue to exist. They did not believe that the science-based Stockpile Stewardship Program, which our laboratories were just beginning to undertake, would actually be able to maintain the arsenal without explosive nuclear testing.

That program, which the Department of Energy maintains through our national laboratories, has been very successful. We believe that thanks to the science-based Stockpile Stewardship Program we now understand more about how nuclear weapons work than we did during the period of nuclear explosive testing.

Furthermore, the international monitoring system is now the heart of the verification regime for the treaty. But the treaty also provides for on-site inspection, and in December 2014 I was in Jordan to observe an exercise designed to show whether it could be verified in this way. To see countries from all over the world, including some countries you would not expect to be working together, such as Iran and Israel, was amazing. We have come a long way since 1999, and I think we are in good shape to be able to answer the questions the senators raised that year.

The treaty is in the national security interest of the United States for other reasons too. Specifically, India and Pakistan are interested in developing more and different types of nuclear weapons, in modernizing the capabilities they already have. China is developing and modernizing its nuclear arsenals.

We must be concerned about these pressures on nuclear testing, and I see the treaty as a clear and significant way to place barriers in the way of a nuclear arms race in Asia. Such an arms race would profoundly affect the national security not only of the United States but of countries around the world. We need to think about what is in our national security interest, and halting or placing barriers in the way of an arms race in Asia is a significant way to ensure the continued security of the American public.

Now how do we go about it? First, we continue to do exactly what we are doing today: we have a conversation with the public. I have been all over the country, visiting states where we once tested nuclear weapons, visiting communities that are downwind of former nuclear test sites and thus suffered from radioactive contamination back in the 1950s and 1960s.

Did you know we tested nuclear weapons in Mississippi? Believe it or not, tests were conducted there in salt domes. Students in the journalism school at the University of Mississippi have made a really interesting film, Atomic Mississippi, about that testing series and the resulting contamination.

Young people are getting excited about this. Once students learn what is going on here and what the treaty can do for the United States and for our national security, it becomes a no-brainer. We have to make the treaty’s value to the United States clear to people around the country, both young and old.

When we get the treaty to Capitol Hill, we have to take the same approach we took with ratification of the New Strategic Arms Reduction Treaty (New START); that is, let the senators ask a lot of questions at briefings, hearings, and individual question and answer sessions.

New START had over a thousand questions for the record. The senators really wanted to dig down deep about the value of the treaty for U.S. national security, and I am confident that once we take CTBT up to the Hill and start to talk about the value of the comprehensive test ban for U.S. national security, we will be able to make that case very clearly.

But we have a lot of work to do. There is no question about it. Nevertheless, I think we have an excellent case to make, and as former Reagan-era Secretary of State George Shultz said, “Senators might have been right voting against the CTBT some years ago, but they would [also] be right voting for it now.”

Siegfried Hecker

Siegfried Hecker

Siegfried Hecker is Research Professor in the Department of Management Science and Engineering and a Senior Fellow at the Freeman Spogli Institute for International Studies and the Center for International Security and Cooperation at Stanford University. He has been a Fellow of the American Academy since 2002.

Twenty years ago, when I was director of Los Alamos National Laboratory, I was in the middle of the debate over ratification of the CTBT. I was asked by the president and by the Pentagon, “Can we deal with the risks of stopping nuclear testing?” – that is, the risk to the U.S. nuclear stockpile.

At the time, my job was to deal with those risks and give the technical answer. I said, “At this point, our stockpile – that is, the nuclear arsenal – is safe, secure, and reliable. However, you need to ask that question again in the coming years.” And, indeed, presidents have asked that question every year since.

President Clinton clearly believed in 1996 that the CTBT was in the security interests of the United States. However, it has not yet been ratified, so clearly some people don’t believe it is in the interest of the United States. I am not one of them.

Testing is important to the United States. You lose something when you don’t test. However, we gain more today than we lose when others don’t test. The United States has conducted 1,054 nuclear tests, some of which were done with the United Kingdom. Russia has conducted 715; France, 210; Britain, 45; China, 45; Pakistan, 6; India, 6; North Korea, 4.

For North Korea, Pakistan, India, and China, an additional test or so will allow them to increase the sophistication or perhaps the diversification of their arsenals, and that can only come back to be a national security risk for the United States.

So, today, the CTBT provides us with an enormous benefit, and I believe we should do everything we can to set the barriers as high as possible for other countries to resume or begin testing. The North Korean example illustrates how alarming nuclear testing is. Everything changed for North Korea in 2006.

But now one has to ask, “Why aren’t all Americans in favor of this? Why are we not able to ratify the test ban today?” Part of the answer is political, the Washington scene, the “anything but Obama” attitude.

However, we must also pay attention to the fact that quite a few people who have a lot of experience in the national security arena do not favor ratification of the CTBT. Their particular concern is, “Can we ensure the safety, security, and reliability of our aging nuclear arsenal without nuclear testing?”

The proponents of the test ban point out, “Look, we have had science-based Stockpile Stewardship. It has been enormously successful. You can do it all with computers today. You don’t need nuclear testing.”

The opponents say, “That’s not true. We are concerned about safety, security, and reliability.”

We need to listen to both sides. Science-based Stockpile Stewardship has been successful, but you do lose some confidence when you don’t test.

The essence of my testimony in 1996 was that we will have to do everything we possibly can to ensure safety, security, and reliability using science-based Stockpile Stewardship without nuclear testing. As we look back now over all of those years, we understand the fundamentals of things nuclear and how nuclear weapons work better than we did in 1996.

However, the U.S. nuclear weapons complex has problems that most people are not aware of. More than just science-based Stockpile Stewardship is needed to make sure the nuclear arsenal is safe, secure, and reliable.

I have concerns about the viability of the entire nuclear complex. I have concerns about the fact that it is so difficult today in our regulatory, compliance-based environment to actually do the laboratory tests that would allow me to assure people that these weapons will still be safe, secure, and reliable when the plutonium or the high explosives age.

I have sympathy for those people who have concerns. However, in my opinion, what we are missing is not actually nuclear testing but the ability to do all the other things in the laboratory, to bring the experiments together with the computational capabilities to be able to make the appropriate assurances.

What I suggest is that we look at what the proponents and the opponents have in common. What is the common ground? Both sides believe in a safe, secure, and reliable arsenal; in other words, that the United States continues to have the nuclear deterrent both for itself and for its allies. Both sides believe that is important.

If we focus on that, then we understand that testing is only one piece and in fact not even the most important thing to do today. If we can agree that what is most important is the stockpile and if we make sure that the nuclear complex actually has the ability to perform the whole range of laboratory experiments and computations necessary for us to take care of the arsenal, perhaps then we might actually convince the opponents of the test ban that it is indeed doable, and that ratification, if it helps to prevent these other countries from testing, is to the great benefit of the United States.

That would be an appropriate direction to go if one wants to take up, as one should, the ratification of the test ban. The other thing I would say is that ratification is sort of a no-brainer once you already do not test. Since we don’t test, we are already subject to the risks of not testing, but we have none of the benefits we would get from a ratified international treaty.

Robert Rosner

Robert Rosner

Robert Rosner is William E. Wrather Distinguished Service Professor in the departments of Astronomy & Astrophysics and Physics, as well as in the Enrico Fermi Institute, the Computation Institute, and the Harris School of Public Policy Studies at the University of Chicago. He has been a member of the American Academy since 2001 and serves as Cochair of the Academy’s Global Nuclear Future Initiative.

As we contemplate the twentieth anniversary of the CTBT, the obvious question is, why modernize the weapons production complex? At least a partial answer lies in the three magic words that Sig already mentioned: safe, secure, and reliable. What are they about? The last one in particular is closely related to demonstrating the general competence of the United States in matters of nuclear weapons, in particular from the point of view of credible deterrence.

This is an issue that becomes more important as we go in the direction that many of us want the United States to go, which is to zero. That is, as the nuclear pile shrinks in size, the reliability of the weapons in the stockpile becomes increasingly important.

In this context, what has the United States actually done? We have the science-based Stockpile Stewardship Program, which involves (1) surveillance of the existing stockpile that is married to a life extension program (LEP), and (2) designing and building a new generation of modeling codes, together with an extensive program to build and maintain certain critical experiments and facilities, such as the National Ignition Facility (NIF), that are designed to increase our understanding of weapons physics and to validate the modeling codes.

Much of our belief in the reliability and the predictive capabilities of the codes rests upon these codes’ abilities to in fact replicate the results of the experiments. Some of these experiments, in particular those involving ignition on the NIF, are probably substantially more challenging to model than nuclear weapons, mostly because certain aspects of the physics involved in driving ignition on NIF remain poorly understood, but are not relevant to weapons physics. This has the important ancillary benefit of allowing the training of weapons scientists without resorting to direct testing of nuclear weapons; in other words, allowing the maintenance of nuclear weapons design capabilities into the indefinite future even in the absence of an actual weapons testing program.

As just mentioned, the stockpile surveillance program is complemented by a refurbishment program, more commonly referred to as the Life Extension Program (LEP). In concert, the Obama administration has moved forward with a thorough modernization of the nuclear weapons production complex, including rebuilding well-known production facilities such as Y-12 in Tennessee and the Kansas City Plant (KCP). What is interesting about this rebuilding effort is that we are not only putting in place the infrastructure to support the Life Extension Program, but we are also putting in place the infrastructure to accomplish in the modern era, at scale, what the United States was able to do when building weapons back in the 1960s, 1970s, and 1980s.

Finally, we have encouraged new technologies. For example, the Nuclear Regulatory Commission approved in 2012 a construction and operating license application from General Electric for a commercial-scale laser enrichment facility at GE’s Wilmington (NC) plant. (Given current uncertainties regarding the price of natural and enriched uranium, it is unclear how quickly GE will move ahead with this project.)

What are some of the consequences of these kinds of activities? First, we have the capability of designing new weapons and new generations of weapons without necessarily relying on testing.

Our certainty in getting things right is diminished because we no longer test, but we also know, for example, from the design competition between Los Alamos and Livermore for the Reliable Replacement Weapon (RRW) that assuring that these weapons will work can be dealt with in the design process. That is, you can dial back on the complexity of a weapon in order to have increased assurance that it will in fact work as designed.

This means that there is a fundamental asymmetry between what the United States is capable of doing and what the vast majority of the other signatories to the CTBT can do: We can do without testing; virtually all of the others cannot.

The experimental data from the more than one thousand tests the United States has conducted form a critical part of the experimental basis for validation of the computer design codes. The other signatories – other than Russia, China, and our allies France and the United Kingdom – do not have this type or scale of data, and thus are reliant on testing to make further progress in building new weapons.

So the CTBT is not an obstacle for us if we were to choose to build a new nuclear arsenal, but it most certainly is an obstacle for almost all of the others. So here is one conundrum: The United States has an interest in maintaining this asymmetry, as it benefits us but not the others. Yet, while we are a signatory to the CTBT, we are the ones who have not ratified it.

A second conundrum involves the Treaty on the Nonproliferation of Nuclear Weapons (NPT). The NPT also has an asymmetry built into it between the “haves” and “have-nots,” and since the signing of the NPT this has been a critical issue for the “have-nots.” They have asked the “haves” – in particular, the permanent members of the UN Security Council (the so-called P5) – why they have not fulfilled their part of the NPT bargain, namely moving expeditiously toward reducing their nuclear stockpiles to zero. In light of that challenge (and here is the conundrum), one may ask: how is the refurbishment program of the U.S. production complex – as actually implemented – consistent with going to zero?

These arguments suggest that the desire to reduce our nuclear stockpile is inherently in conflict with the need to ensure that as long as the stockpile exists, its weapons are reliable, and hence credible: that is, the activities necessary to ensure the reliability of the stockpile are the very activities that also ensure that we maintain the capability to rebuild the stockpile at any time, well into the future. This is not good news for those of us who want to see the nuclear stockpile eventually disappear altogether.

Arun Rath

Arun Rath

Arun Rath is a correspondent for NPR and Boston-based public broadcaster WGBH News.

I would like to ask our distinguished panel some questions. First, is there a way to talk about history and to get across to people that there is a stake in this? Our country is often criticized for not being too aware of history.


Rose E. Gottemoeller


History is certainly important. I have found one of the biggest challenges we have is conveying a sense of the horrors of nuclear war to the young generation. Since the end of the Cold War, nuclear weapons have gone on the policy back burner as well as the back burner of public consciousness.

So I have been looking for ways to re-enliven that history. One way is to mention the history of the spies who were so important to the Soviet nuclear weapons program. The recent film Bridge of Spies is a good look at the battle over the secrets that led to nuclear weapons programs being successful in the 1950s.

The second point is to wake people to the horrors of nuclear war and an attack on our cities. I remember in 1983 seeing The Day After, which was a television film about a nuclear attack on the United States.

More recently, I was glad to see that The Americans, a TV show about spies embedded in American society, built an episode around the showing of The Day After. If you have not seen it, I recommend it because it is a really good way to get your head around some of the horrors of nuclear war.


Arun Rath


Under Secretary Gottemoeller, in 2010 you were involved in negotiating the New Strategic Arms Reduction Treaty. The context was different from what we have now – you were negotiating with the Russians not the U.S. Senate – but can you draw lessons from that experience?


Rose E. Gottemoeller


That is a very good question. The senators who were willing to take the ratification process seriously really dug deep to understand the technical details of New START. They wanted to understand how the central limits of the treaty fit together. They wanted to understand its impact on our future nuclear forces. They wanted to understand how the onsite inspection regime worked. That is why we answered over a thousand questions for the record and why I was up on the Hill countless times, briefing individual senators and meeting with groups of senators to answer their questions.

What I found – and I think it is a hopeful sign for our system – is that they took their constitutional responsibility seriously. Once they got over the hump of the politics, they really wanted to dig down, understand the treaty, and make a sound decision on behalf of the nation.

That is why I feel if we have the opportunity to make the case for the Comprehensive Nuclear-Test-Ban Treaty that at least some senators will be willing to dig deep. Not all. Some will say, “It’s the Obama administration. Forget about it.” Some will say, “It’s a nuclear treaty. Forget about it.” But some will listen and will be willing to engage on this treaty.


Siegfried Hecker


In my discussions with Chinese nuclear colleagues about the CTBT, they say, “We’ll ratify five minutes after you do.” So, if we had ratified in 1999, we would have China in play, and, although I don’t think it would have made much difference with North Korea, probably Pakistan and India also. So, as far as our own situation goes today, our problems are self-inflicted.

Some people have worried that ratification would lead the United States to forget altogether about its nuclear weapons complex, and things might actually be worse. I don’t think so. I think we just have not made the case sufficiently clearly.


Robert Rosner


This is pure speculation, but I think the credibility of the design labs might have been much stronger had we actually ratified. Without ratification, the importance of design labs to the whole enterprise has been, quite frankly, neglected, as evidenced, for example, by the serious decreases in the design lab budgets as funds have been shifted to the production complex.


Arun Rath


I am a reporter and maybe I am part of the problem of why people are not interested. There seems to be a feeling that people, at least in this country, are not as concerned as they should be about this issue and about issues around nuclear proliferation in general. What can I communicate to them? What is not getting out there? What is not being reported?


Robert Rosner


The great fear I have is that the longer we proceed without ratification, with the treaty not in force, the more some countries will be rethinking their nuclear posture.

Pakistan is an example of that. They are thinking of going in directions that are beginning to blur the distinction between strategic and tactical weapons. So the risks of actually having a real nuclear exchange are going up. That is what is at the heart of the issue. In a world without the CTBT in force, the risks are just going to get worse and worse.


Siegfried Hecker


I teach students at Stanford. One of the classes I teach (along with Secretary Bill Perry) is about technology and national security, which has had an enrollment of about 250 people each year for the last ten years.

Typically, the way I try to get the students interested in nuclear issues is by helping them to understand the incredible power of splitting the nucleus. With that power you can either electrify the world, do good, or you can destroy the world. The key is, how do you manage that? How do you get the good but not destroy the world?

I tell them, “It is going to be your job because we haven’t quite figured it out.” We still have potential arms races, still have not ratified the CTBT. I try to get them to focus on the benefits, on electrifying the world while hopefully making some dent in global climate change. Global warming is the part they are actually most concerned about. So I try to put it in those terms.


Rose E. Gottemoeller


I would say the problem is the crowded media environment. Nuclear issues are not on the front pages. Instead, it is the terrorism threat, it is ISIL, it is our election campaign. And it is not just nuclear issues but WMD issues in general that get crowded out.

Sometimes they jump to the fore again. For example, when chemical weapons were used in Syria, chemical weapons were on the front pages for a while. But the media space is crowded, and unless we have another Cuban Missile Crisis – which would be terrible – not much attention gets paid to nuclear weapons.


Arun Rath


Can we talk about the beneficial side effects that have resulted from the work that has been done on this treaty, particularly the system of sensors that has been developed?


Lassina Zerbo


For the past ten years we have been discussing the construction of a station in Luxor, Egypt, trying to get an agreement to start the civil work. We have done the site survey, and we have done the training necessary for the Egyptians to operate and maintain the station after it has been built, but things have been stuck for some time now.

But we are stationed in Israel and contributing to the International Monitoring System, and we have a station in Turkmenistan, and we are hoping that the station that was certified in Iran will, before long, resume sending data to the International Data Centre in Vienna and thus improve the global coverage of the International Monitoring System.

But the sensors can do much more than just monitor for potential nuclear tests. For example, they can contribute to tsunami warnings. More recently, Fukushima showed how we could contribute to monitoring the dispersion of radioisotopes emanating from a nuclear accident.

With an accident of this nature, people learn more about what the CTBT can do. We always seem to wait for disasters or for catastrophe before we realize the importance of this great achievement of the modern world, which is how Secretary Kerry has described the International Monitoring System.

© 2016 by Lassina Zerbo, Rose E. Gottemoeller, Siegfried Hecker, Robert Rosner, and Arun Rath, respectively

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