The alliance between the Republic of Korea and the United States has been facing new pressures in recent months. Leaders in Washington and Seoul are visibly out of synch in their response to the escalatory actions of North Korea, beginning with the July 4 missile tests and leading to the October 9 nuclear explosion. South Korean leaders seem more concerned with the danger that Washington may instigate conflict than they are with North Korea's profoundly provocative acts. American officials increasingly see Seoul as irrelevant to any possible solution to the problem. Officials on both sides valiantly try to find areas of agreement and to paper over differences. If attempts to restart the six-party talks on North Korea falter again, it is likely this divide will resurface.

There is a tendency on both sides of the Pacific to overdraw a portrait of an alliance on the verge of collapse. Crises in the U.S.-ROK alliance are hardly new. As I have written elsewhere, there never was a "golden age" in our alliance that was free from tension. Korean discomfort with an alliance founded on dependency and American unease with Korean nationalism has been a constant since the early days of this relationship. Clashes over how to respond to North Korea have been a staple of the alliance since its earliest days.

Korean-American relations today are much deeper than at the inception of this alliance. Our interests are intertwined on many fronts, not least as major players in the global economic and trading system. We share fundamental values as democratic societies, built on the rule of law and the free flow of ideas. There is a large, and growing, contact between our two peoples, from trade and tourism to immigration.

The current situation is worrisome however because it threatens the security system that lies at the foundation of the alliance. Though our interests are now far broader, the U.S.-ROK alliance remains military in nature. The founding document of this alliance was the

Mutual Defense Treaty signed on October 1, 1953, following the conclusion of the armistice pact to halt the Korean War. That treaty has been significantly modified only once - 28 years ago in response to American plans to withdraw its ground forces from Korea - to create the Korea-U.S. Combined Forces Command (CFC).

The two militaries have a vital legacy of decades of combined command, training and war planning. American military forces in significant numbers have remained in place to help defend South Korea from potential aggression from the North. South Korean troops have deployed abroad numerous times in support of American foreign policy goals, including currently in Iraq and Afghanistan.

This foundation of security is not only essential to this alliance but is the very definition of the nature of alliances in general, as distinct from other forms of cooperation and partnership in international relations.

"Alliances are binding, durable security commitments between two or more nations," Dr. Elizabeth Sherwood-Randall, a Stanford scholar and former Clinton administration senior defense official, wrote recently. "The critical ingredients of a meaningful alliance are the shared recognition of common threats and a pledge to take action to counter them. To forge agreement, an alliance requires ongoing policy consultations that continually set expectations for allied behavior."

Alliances can survive a redefinition of the common threat that faces them but not the absence of a threat. Nor can alliances endure if there is not a clear sense of the mutual obligations the partners have to each other, from mutual defense to joint actions against a perceived danger. "At a minimum," Sherwood-Randall says, "allies are expected to take into consideration the perspectives and interests of their partners as they make foreign and defense policy choices."

By this definition, the U.S.-ROK alliance is in need of a profound re-examination.

The 'shared recognition' of a common threat from North Korea that was at the core of the alliance is badly tattered. As a consequence, there is no real agreement on what actions are needed to counter that threat.

There is a troubling lack of will on both sides to engage in policy consultations that involve an understanding of the interests and views of both sides, much less setting clear expectations for allied behavior. Major decisions such as the phasing out of the CFC have been made without adequate discussion.

Americans and Koreans need, in effect, to re-imagine our alliance. We should do so with the understanding that there is still substantial popular support for this alliance, despite conventional wisdom to the contrary. The problems of alliance support may lie more in policy-making elites in both countries than in the general public. That suggests that a concerted effort to reinvigorate the alliance will find public backing.

The results of the Chicago Council on Global Affairs 2006 multinational survey of public opinion show ongoing strong support for the American military presence in South Korea. Some 62 percent of Koreans believe U.S. troop levels are either about right or too few; some 52 percent of Americans share that view. A slightly larger percentage of Americans - 42 percent compared to 36 percent of Koreans - think there are too many U.S. troops. Along the same vein, 65 percent of Americans and 84 percent of Koreans favor the U.S. providing military forces, together with other countries, in a United Nations-sponsored effort to turn back a North Korean attack.

The crack in the alliance comes over the perception of threat from North Korea.

While some 79 percent of Koreans feel at least "a bit" threatened by the possibility of North Korea becoming a nuclear power, only 30 percent say they are "very" threatened. Fewer Koreans feel the peninsula will be a source of conflict than the number of Americans. More significantly, nuclear proliferation is viewed as a critical threat by 69 percent of Americans, compared to only half of Koreans (interestingly, Chinese are even less concerned about this danger).

The opinion poll was conducted before the nuclear test so it is difficult to judge the impact of that event. These survey results do clearly indicate however that while the security alliance still has support, there is an urgent need for deep discussion, at all levels, about the nature of the threat.

The crisis that faced the NATO alliance in the wake of the end of the Cold War has some instructive value for Koreans and Americans today. At the beginning of 1990, I was sent by my newspaper, the Christian Science Monitor, from Tokyo, where I had been covering Japan and Korea since the mid-1980s, to Moscow. The Berlin Wall had fallen a few months earlier and the prospect of the end of a half-century of Cold War in Europe was in the air. However, I dont believe anyone, certainly not myself, anticipated the astounding pace or scale of change that took place within just two years.

Within less than a year, in October of 1990, West and East Germany were reunited.

The once-mighty Soviet empire in Eastern Europe disintegrated almost overnight. By July of 1991, the Warsaw Pact had come to an end. Perhaps most astounding of all - not least to officials of the administration of George H.W. Bush - the Soviet Union fell abruptly apart in December 1991.

These tectonic events triggered a debate about the future of the NATO alliance that had provided security to Europe since it was founded in April of 1949. Soviet leader Mikhail Gorbachev somewhat famously - and perhaps apocryphally - anticipated this debate. "We are going to do something terrible to you," he is said to have told Ronald Reagan. "We are going to deprive you of an enemy."

In those early days, the very continued existence of NATO was under active discussion. The Soviet leadership called for the creation of entirely new "pan-European" security structures that would replace both NATO and the Warsaw Pact. Some in Europe favored the European Union as a new vehicle for both economic integration of the former

Soviet empire into Europe, along with creating new European security forces that would supplant NATO's integrated command.

A more cautionary view argued for retaining NATO without change as a hedge against the revival of Russia as a military threat or the failure of democratic and market transformation in the former Soviet Union. American policymakers opted instead for the ambitious aim of expanding NATO membership to absorb, step by step, the former Soviet empire, including the newly freed western republics of the Soviet Union.

Along with expansion, the United States pushed NATO to redefine the "enemy." Americans argued that new threats to stability and security from ethnic conflict - and international terrorism - compelled NATO to "go out of area or out of business." NATO did so first in the Balkans, in Bosnia and Kosovo, though reluctantly. The alliance has moved even farther beyond Europe to Afghanistan, where NATO commands the international security forces. This draws upon the invaluable investment made in joint military command and operations that are the foundation of the alliance.

Certainly NATO's transformation is far from complete. As was evident at the most recent NATO summit in Riga, considerable differences of opinion remain between many European states and the United States over the mission of NATO. Europeans tend to still see NATO as an essentially defensive alliance, protecting the "euro-Atlantic" region against outside aggression, with an unspoken role as a hedge against uncertainties in Russia. They are resistant to continued American pressure for expansion - including a new U.S. proposal to move toward global partnership with countries such as Japan, South Korea and Australia.

But the reinvention of NATO after the Cold War provides some evidence that even when the nature of the threat has changed, security alliances can preserve a sense of common purpose.

A re-imagined U.S.-ROK alliance could draw from the NATO experience by including the following elements:

HEDGE - The alliance remains crucial as a 'hedge' against North Korean aggression, even if the dangers of an attack are considered significantly reduced. If North Korea retains its nuclear capability, that hedge will need to expand to include a shared doctrine of containment and deterrence, including making clear that the U.S. will retaliate against use of nuclear weapons, no matter where it takes place. Strategically the alliance is also a 'hedge' against Chinese ambitions to dominate East Asia and a guarantor of the existing balance of power;

EXPANSION - The alliance can reassert its vitality as the basis, along with the

U.S.-Japan security alliance, of an expanded multilateral security structure for

Northeast Asia;

NEW MISSIONS - The alliance should take on new missions, most importantly to participate in military and non-military counter-proliferation operations;

OUT OF AREA - A re-imagined alliance might formalize an "out of area" role, elevating the deployments of peacekeeping and other forces to Iraq and Afghanistan into more systematic joint global operations between the two militaries. In this regard, the participation of South Korea in a program of global partnership with NATO, most importantly in the area of joint training, merits serious discussion.

There is another alternative: South Korea and the United States can chose to bring their alliance to a close. If we cannot agree on the common threats that face us, this alliance cannot endure. What we should not do is to allow the alliance to drift from inattention into a deeper crisis that would only benefit our adversaries.

(This article is based on a presentation by the author to the 1st ROK-U.S. West Coast

Strategic Forum held in Seoul on Dec. 11-12, 2006).

This article appeared on the website of the Maureen and Mike Mansfield Foundation.

Reprinted with permission from the Maureen and Mike Mansfield Foundation.

It is tempting to dismiss President Bush's travel through Southeast Asia as aimless floating by a doubly lame duck. Getting things done will be harder without either the right to run for a third term in 2008 or the support of a legislative majority between now and then. But if that means having to work with others, at home and abroad, these new limits could be a virtuous necessity -- an opportunity to shed his administration's my-way-or-the-highway image and reverse the squandering of American legitimacy and leverage around the world.

Asia is a good place to begin rebalancing U.S. foreign policy because it is huge, it is dynamic -- and it is not Iraq. The Asia Pacific Economic Cooperation summit that the president is attending in Vietnam this weekend includes leaders from 21 economies that jointly account for 56, 48, and 40 percent, respectively, of global GDP, trade and population. Since 1989, the forum's economies have grown 26 percent compared with 8 percent for the rest of the world. The Middle East looks trivial by comparison.

The Middle East also lacks a tradition of successful multilateral cooperation. But if the Arab League has accomplished little, Southeast Asia is an exemplar of regional harmony. Cynical observers may deride as mere "talk shops" the many overlapping frameworks that span or involve Southeast Asia. On its calendar of events in 2005 the Association of Southeast Asian Nations listed 612 meetings. But talking is better than fighting, and no two ASEAN members have made war on each other since the group was formed nearly 40 years ago.

Northeast Asia is another matter. There is no ANEAN -- no Association of Northeast Asian Nations. Mistrust among China, Japan and South Korea is still too deep. But North Korea's decision to rejoin the Six-Party Talks (among China, Japan, Russia, the two Koreas, and the United States) has revived the prospect that these conversations could evolve into a framework for broader security in Northeast Asia. Of the six, all but North Korea will attend the economic summit this weekend in Hanoi. On the sidelines of that event, President Bush and his delegation should discuss with these five counterparts a possible shared strategy on North Korea when the talks reconvene, probably in China later this year.

Another key goal for the president on this trip should be helping to revitalize APEC. The "Doha round" of global trade liberalization has run aground. Without a last-minute push, APEC's goals of "free trade" among advanced economies by 2010 and among developing ones by 2020 will not be met. Meanwhile, bilateral trade agreements among APEC members have proliferated. The result is a "noodle bowl" of inconsistent arrangements that may, on balance, divert as much trade as they create. There is, for example, no consistent definition of the "rules of origin" that determine which items benefit from lowered barriers and which do not. Without lowering the quality of all these many bilaterals to their lowest common denominator -- i.e., the least liberal arrangement any signatory will accept -- an effort should be made to link and standardize them so that trade flows are enlarged and not merely redirected.

This may seem like a non-starter. On Monday, the House of Representatives failed to approve permanent normal trade relations with Vietnam. And that was even before the newly elected and arguably more protectionist Democratic majority is seated in January. But progress can still be made in Vietnam.

An advantage of the Asia Pacific Economic Cooperation summit for the United States is that it includes both China and Taiwan, and excludes the repressive regime in Burma. But APEC's uniquely trans-Pacific character is a more important political reason for strengthening the grouping. While APEC has lagged, East Asian regionalism has boomed. That has been good for East Asia. But U.S. and East Asian interests alike could be hurt if the Pacific Ocean ends up being split between rival Chinese and American spheres of influence.

The risk of gridlocked government should not keep the United States from seeking to deepen Asia-Pacific economic and political cooperation. The Bush administration may be a lame duck. But even a healthy duck needs a tranquil pond.

Donald K. Emmerson heads the Southeast Asia Forum in the Shorenstein Asia Pacific Research Center at Stanford University. He wrote this article for the Mercury News which was printed on Sunday, November 19, 2006. Reprinted with permission from the San Jose Mercury News.

To read the seismic signal sent from an abandoned coal mine in the mountains of North Korea's coast, you must first recognize that it represents four major failures, two grave dangers, and one big opportunity.

The apparent explosion of a nuclear device, coming after two decades of trying to stop North Korea from achieving this goal, is a manifest failure of policy on four fronts -- a failure of U.S. nuclear non-proliferation policy, a failure of international diplomacy, a failure of Chinese leadership and a failure of South Korea's strategy of engaging the North.

Having failed so completely, the world now faces two grave dangers. The first is the very real threat of war on the Korean Peninsula, triggered by a series of escalatory actions in the wake of the bomb test. The second is the danger that North Korea will proliferate its nuclear technology, materials or know-how to others -- not the least to another nuclear hopeful, Iran.

But there remains a lone and tenuous opportunity. Having removed all ambiguity about its nuclear ambitions, North Korea may finally have created a common sense of threat that will galvanize the kind of concerted international action that so far has been absent.

THE FOUR FAILURES

Non-proliferation failure

The United States has spent two decades trying to stop North Korea from going nuclear, a turbulent period of crisis and negotiation that even went to the brink of war. At least three administrations confronted this problem and none, certainly not the Bush administration, can escape blame.

North Korea agreed to sign the Nuclear Non-Proliferation Treaty (NPT) in 1985, but it stalled before signing an agreement with the International Atomic Energy Agency (IAEA) in 1992 to place its nuclear facilities under international safeguards and inspections. During that time the North Koreans reprocessed some spent fuel from their reactor into plutonium - an amount that American intelligence believes was enough for building one or two warheads.

North Korea's resistance to full inspections, while it kept pulling spent fuel rods out of its reactor, provoked a crisis in 1994 and led the Clinton administration to ready military forces to strike the North's nuclear facilities. In a last-minute deal, North Korea froze its reactor and reprocessing facilities, effectively halting plutonium production under IAEA supervision. In exchange, the United States, Japan, South Korea and others agreed to construct two light-water reactors for North Korea and to supply fuel oil until the reactors came online.

The deal was troubled from the start. Neither party was satisfied with the compromise or the way it was to be implemented. By the late 1990s, the North had begun a secret effort to acquire uranium-enrichment technology from Pakistan and, in 1998, tested a long-range ballistic missile. Despite this, the plutonium freeze remained in place. But it did not survive the Bush administration.

The Bush administration came into office challenging the value of the agreement and froze contacts with the North. After receiving intelligence showing moves to build enrichment facilities, it confronted North Korean officials at an acrimonious meeting in Pyongyang in October 2002.

The United States halted fuel shipments a month later, and, in early 2003, the North Koreans expelled IAEA inspectors and withdrew from the Non-Proliferation Treaty. They proceeded to reprocess the fuel rods they had stored for a decade, producing enough plutonium, intelligence estimates say, for four to six nuclear warheads. In February 2005, the North Koreans announced they had manufactured nuclear weapons. Last week, they apparently made good on that declaration.

Blame aside, North Korea's emergence as the world's ninth nuclear power may be the most serious failure in non-proliferation history. Unlike India and Pakistan, which remained outside the system of international treaties, North Korea acted in defiance of those controls. Who might be next?

Diplomatic failure

Unlike Iraq, the attempt to stop North Korea's nuclear program has relied on the tools of diplomacy, accompanied by economic incentives and coercive sanctions.

But serious questions have been raised from the start about the sincerity and methods of the diplomatic efforts, particularly on the part of the United States and North Korea. The Bush administration has insisted -- and the president continues to make this argument -- that direct talks with North Korea do not work. Pyongyang has tried to frame everything as an issue with Washington, undermining talks that involved others, including South Korea.

Bush's stance lends credibility to those who charge the administration seeks "regime change," not a compromise that it believes will lend legitimacy to Kim Jong Il. The North Koreans now appear to have used the talks to buy time and build bombs.

Diplomacy has, at American insistence, consisted of six-party talks, held under Chinese auspices and including both Koreas, Japan and Russia. In truth, little real negotiating went on at these gatherings, at least until the last full round of talks in September 2005. In contrast to the thousands of hours of negotiations between Americans and North Koreans that led to the 1994 deal, there have been only tens of hours of actual give and take.

It is intriguing that the September agreement on a statement of principles for denuclearization came only after the State Department's chief negotiator was finally allowed to talk to his North Korean counterpart at length. Even then, their agreement evaporated almost immediately as they dueled publicly over the deal's meaning. American financial sanctions against North Korean currency counterfeiting further clouded the atmosphere, and direct contacts ground to a halt.

China's failure

The North Korean nuclear crisis is also a failure of China's bid for regional, if not global leadership. North Korea is an ally of China, a relationship that goes back more than half a century to the Korean War, when Chinese "volunteers" poured across the border to prevent an American victory. Their relationship has become more difficult since China embarked on market reforms while North Korea clung to its peculiar brand of Stalinism.

China has been torn between its loyalty to Pyongyang, its desire to maintain a stable balance of power in the region and its fear that the North's nuclear ambitions could provoke conflict on its borders. By becoming host for the six-party talks, Beijing stepped into an unusual leadership role.

The Bush administration was eager to move the burden of the North Korean problem onto the Chinese. Some administration hard-liners argued that China had the power to trigger the collapse of Kim Jung Il's regime by cutting off energy and food supplies.

Time and again, Beijing dragged the North Koreans back to the negotiating table, while also pushing Washington to engage Pyongyang in the talks. But Chinese irritation over American inflexibility has now been trumped by North Korea's defiance. Chinese policy-makers now wonder how they can punish the North without creating chaos, or war.

Failure of engagement

The final failure lies on the doorstep of South Korea's 10-year-long policy of engagement. The "sunshine policy" asserted that the North could be induced to give up its nuclear option by opening up the isolated communist state and promoting the forces of Chinese-style reform.

After a historic summit meeting in 2000, South Korean aid and trade, even tourists, flowed into the North. South Koreans lost their fear of a former foe, seeing it more as an impoverished lost brother than a mortal threat. Tensions with their American allies rose because of a gap in the North's perceived threat. The United States wondered why its troops should continue to defend South Korea.

Now South Koreans must confront the possibility that the North may have used engagement only to buy time.

THE TWO DANGERS

Threat of war

With eyes on Iraq and the Middle East, the Korean Peninsula has been far from the center of American attention. American forces based in South Korea and Japan have been dispatched to Iraq.

Yet the demilitarized zone that separates the two Koreas remains the most militarized frontier on the planet, with hundreds of thousands of well-armed soldiers poised against each other. Clashes along that frontier used to be commonplace and there are signs of a renewal of tensions. The danger of unintended escalation cannot be dismissed.

What might happen if a U.S. naval vessel, moving to inspect a North Korean freighter - as the U.N. resolution may authorize - is fired on or even captured, as the USS Pueblo was in 1968? It is a frightening scenario already worrying some at the Pentagon and the State Department.

Risk of proliferation

More than anything else, American policy-makers fear that North Korea, emboldened by its nuclear success and perhaps desperate for funds amid economic sanctions, might sell its nuclear expertise to Iran and others, including terrorist groups.

For Pyongyang, an alliance with Iran is a logical response to American and global pressure. The North Koreans have sold ballistic missiles to Tehran since the 1980s and rumors of nuclear cooperation persist.

An American effort to interdict the movement of ships and planes to Iran -- with possible U.N. backing - is probable. But the most likely transit is across the long and loosely controlled land border with China. The amount of plutonium needed to make a warhead is the size of a grapefruit and hard to detect - creating yet another nightmare scenario.

THE OPPORTUNITY

In this otherwise bleak landscape, there is an opportunity. For the first time, there is a chance of a consensus among the key players -- China, Japan, South Korea, Russia and the United States. The passage of a U.N. resolution is a small step in that direction. But the real test will come next, as the nations must cooperate to put pressure on North Korea, while coolly navigating the perils of war and making sure to leave open a diplomatic exit.

There is a slim chance of such concerted action, and a limited window for achieving it. Not everyone sees the dangers the same way. Signs of rethinking errors of the past are no more evident in Beijing and Seoul than they are in Washington or Tokyo. Ultimately, however, if they are to seize this moment of opportunity, all parties must face up to the fact that the policies of the past have failed.

GWS (Gi-Wook Shin): Dr. Hecker, could you please briefly explain the technical dimensions of what has happened? North Korea is claiming great success, but there are some questions about whether this presumed nuclear test was really successful or meaningful.

SH (Siegried Hecker): At this point, as I understand it, the North Koreans have conducted what they call a nuclear test.

South Korea has said seismic signals appear to indicate a 0.5 kiloton, or sub-kiloton, explosion. From reports I have seen, the Australians and the French believe the blast was about 1 kiloton. Thus, three countries have given assessments on the power of the underground explosion, ranging between 0.5 kilotons and 1 kiloton, or 500 and 1000 tons. This likely indicates a nuclear explosion of a relatively low yield, compared to what one would typically expect. Although the Russian defense minister has apparently commented that the explosion was between 5 and 15 kilotons, I have not heard any other nation estimate in this range.

By comparison, the Nagasaki bomb was approximately 20 kilotons, and the initial tests of the five major nuclear powers were all quite large, on this order. Also, when both India and Pakistan tested multiple devices in 1998, some of these tests were of a substantial yield, at least 20 kilotons. But each country also tested three devices that were said to result in explosions of less than a kiloton. Whether these devices did not work or were experimental in nature is still unknown. So, a test on the order of that conducted by North Korea is not unheard of, but it is apparent that the North Korean device produced an explosion considerably smaller than most countries' first nuclear tests.

Regarding the technical dimensions of this event, I would offer two provisos: first, we must give scientists more time to analyze the seismic signals, and second, we must allow more time for analysis of how those seismic signals translate to the yield of the device. This latter task involves a thorough understanding of relevant geology - scientists make models to predict this, but there is always some uncertainty.

GWS: Given the relatively low yield of the test, is it possible that what North Korea has "tested" is not a nuclear device but very powerful conventional weaponry?

SH: It is most likely that this was indeed a nuclear device. There are two plausible explanations for why this test resulted in a relatively low yield. One possibility is that the North Koreans attempted to test a relatively simple nuclear device that was meant to be large, but it did not work quite right. There are two reasons the test of such a device might not have gone as planned. First, the detonators might not have exploded at exactly the right time or the explosive might not have been of the right quality, thus producing a lower yield. Second, if the timing of the "initiator" (additional neutrons that are introduced) was not quite right, this could also decrease the expected yield of the device.

Another possibility is that North Korea was actually trying to test a smaller, much more sophisticated nuclear device, one with a lot of instrumentation to monitor implosion. North Korea could have learned a great deal from such a test, but I would be surprised if the country had really designed the device to be that small.

GWS: This test marks the failure of the disparate policy approaches of South Korea and the United States - neither nation was successful in arresting DPRK nuclear development. But just how advanced North Korea's nuclear program is remains unclear. In the Korean media, there has been debate over whether North Korea's nuclear test was a success or a failure. What do you think?

SH: I would not say that the test failed. It is simply too early to judge, and we do not know exactly what North Korea had hoped to achieve. If North Korea wanted to use this test as a demonstration, then perhaps it was not very successful. It may be the case that the test did not work as well as anticipated if the device in question was a simple nuclear device. If North Korea was testing an advanced designed that was very well instrumented and monitored, it may have learned a great deal from this test.

It is important to wait to see an accurate yield for this test and then to look at the range of possibilities for why it might have been executed. From a scientific perspective, it is important not to overreact and not to go beyond what is actually known.

GWS: You said previously that when India and Pakistan tested nuclear devices in 1998, they both set off multiple explosions. Is it correct that North Korea has set off a single explosion?

SH: From what we have learned so far, it appears that North Korea has tested one device. This is what the North Koreans announced they would do. Scientists will have to carefully analyze the seismic signals to be sure, however, as for example, when India tested, it set off two devices simultaneously. We have not yet seen all the seismic evidence.

GWS: If North Korea were to use such a "low yield" device as a weapon in a major metropolis like Seoul, what kind of impact would it have?

SH: A 1 kiloton bomb in a major metropolis, though a relatively "low-yield" nuclear device, would still be devastating and catastrophic. Many thousands would experience instant death, and due to radioactivity, there would also be many delayed deaths. A device of this size would not wipe out the entire city, as was largely the case in Hiroshima and Nagasaki, but it would cause major, significant damage.

GWS: Based on the scale of the explosion, was this device something that even terrorists could assemble?

SH: One kiloton in terrorist hands would indeed be catastrophic. I am very concerned that North Korea's nuclear material might fall into terrorist hands.

GWS: The possible marriage of this demonstrated nuclear capability and North Korean missiles is extremely dangerous. With reference to the North's nuclear and missile capabilities, is testing useful for making smaller nuclear devices - devices small enough to be placed on a missile?

SH: If North Korea is intent on making a nuclear warhead, this test could be a step in that direction. Making smaller nuclear devices by nature means making more complex nuclear devices. For much of the Cold War, this was a major goal for both the Soviets and the Americans. For North Korea, at this point we cannot say that the test was successful in terms of this aim of miniaturization, though again, North Korean scientists may have learned a lot in this regard. It is extremely difficult to say how soon North Korea could achieve miniaturization with the limited information we have about this test.

Miniaturization is a very big step, and it cannot be accomplished without nuclear testing. This could have been one of the most important reasons that North Korea undertook this test. It must be noted that their missiles are the other part of this equation, and there is not great confidence in the reliability of these missiles, especially those that performed poorly during the July test.

GWS: North Korea has certainly made a political statement with its nuclear test, but from a technical perspective, do you expect additional testing? What is your assessment of North Korea's technical capabilities, in light of your recent visits to the nation?

SH: At this point, North Korea could want another test for two technical reasons. First, if this was a simple device, they will want to fix the problem and demonstrate an explosion of a higher yield. If this was a more advanced design, they may have learned a lot but would still desire another test in order to gain an appropriate level of confidence in the device.

In January 2004, I visited the Yongbyon nuclear reactor and in August 2005, I visited Pyongyang. On the basis of those visits, I would estimate that North Korea has enough plutonium for 6 to 8 nuclear devices, though there is some degree of uncertainty in that estimate. Overall, I estimate the North has 40-50 kilograms of weapons-grade plutonium, and generally 6-8 kilograms are required for each weapon. I also estimate that North Korea could gain one additional weapon per year, given the current rate of reprocessing.

In terms of skilled people and facilities, North Korea has very good capabilities, up to the point of and including reprocessing plutonium. However, to go from reprocessing plutonium to building the device itself takes a whole new set of engineering and physics skills.

GWS: Given North Korea's limited amount of weapons-grade material, its government would presumably want to conserve as much as possible, right?

SH: Yes, and this is probably one of the reasons North Korea did not set off multiple explosions like India and Pakistan did. North Korea has very limited material, and therefore it will want to be judicious. With this conservation imperative, North Korea will want to fully assess what has been learned from this first test before it attempts a second test.

GWS: From a technical perspective, is it difficult to say how long it may be until North Korea conducts a second test?

SH: Yes, it is very difficult to say, because it depends on factors related to this test about which we are still uncertain. If North Korea was satisfied with this test and all preparations have already been made, a second test could take place within a few days. Yet if the findings from this test surprised North Korea, the device may have to be rebuilt, and that could take weeks or months. One thing we know for sure is that they do not have a lot of weapons-grade material, and they will have to carefully judge how to use it.

GWS: You have said that a major danger from the North Korean nuclear program is the possibility of plutonium transfer. How serious is this possibility? Are you also concerned about transfer of nuclear technology?

SH: Well, a test does mean that there is now less material that could possibly be transferred.

I feel strongly that the principal danger from the North Korean program is the plutonium itself, and the possibility it would find its way to a third party, perhaps into terrorist hands or into the hands of other nations. The reason I believe this is the biggest danger is that North Korea could be restrained by its neighbors from ever actually using a nuclear device, but a third party, especially a non-state actor, may not be "restrainable."

The nuclear test will not have an impact on how marketable the plutonium is. Yet, for the export of nuclear technical know-how, a successful test could make a big difference in the appeal of North Korean technology, especially to a nation like Iran.

GWS: The current nuclear crisis erupted in October 2002, when U.S. officials confronted North Korea about its possession of a uranium enrichment, or HEU, program. North Korea has thus far denied having such a program. I understand this type of program is much more difficult to detect. Would a uranium-based device require testing?

SH: North Korea has stated that it does not have an HEU program. My own opinion is they have some type of enrichment program, owing to Pakistani President Musharraf's statements that his nation provided Pyongyang with some of the required technology and equipment. We simply do not know how far North Korea has progressed in this program.

The HEU program is very difficult to detect - there are fewer signatures than for a nuclear reactor and this type of program is easier to conceal, given the smaller size of the facilities required. However, if we assume statements made by A.Q. Khan and President Musharraf are accurate, it may be some time before North Korea can produce significant quantities of HEU.

Once North Korea has accomplished this, a uranium bomb will be easier to make, and North Korean scientists will have more confidence in this type of device without testing.

GWS: All indications are that North Korea will be further isolated after this test. Will this increased isolation impact the country's continued nuclear development?

SH: At this point, from what I saw at Yongbyon, current North Korean operations do not depend on external help or supplies. Thus, isolation makes little difference in this regard. For the uranium program, technical isolation would probably cause a slowdown, because North Korea would benefit from additional technical purchases from the outside world. But the uranium program does not appear to be a centerpiece of North Korea's nuclear efforts.

GWS: After this nuclear test, is the situation more dangerous?

SH: I believe the major threat came around 2003 when North Korea reprocessed a major amount of plutonium, thus crossing the threshold to become a major threat. I have always taken the North Korean threat very seriously, and I believe all the governments and peoples involved should take it very seriously as well. First and foremost, the imperative should be to make sure that nuclear materials stay in North Korea and are not transferred to third parties.

Transcript prepared by Kristin Burke, Shorenstein APARC Research Associate