Mitchell B. Reiss and Robert L. Gallucci

As individuals who have negotiated with North Korea and are well versed in the development of Pyongyang's nuclear programs through our service in the Clinton and Bush administrations, we feel compelled to comment on Selig Harrison's "Did North Korea Cheat?" (January/February 2005) in order to clarify a number of the misstatements and misunderstandings in Harrison's article. The most serious of his allegations are that the Bush administration has politicized the question of North Korea's uranium-enrichment program; that U.S. allies and partners in the six-party talks do not share Washington's assessment of that program; and that the enrichment program is somehow not central to resolving the nuclear challenge Pyongyang poses to its neighbors and the world.

The United States, for a number of years, has had well-founded suspicions that North Korea has been working on the enrichment of uranium. Indeed, in both 1999 and 2000, the Clinton administration was unable to certify to Congress that North Korea was not pursuing a uranium-enrichment capability. (This fact alone should dispel claims of partisanship on this point.) In mid-2002, the Bush administration obtained clear evidence that North Korea had acquired material and equipment for a centrifuge facility that, when complete, could produce enough weapons-grade uranium for two or more nuclear weapons per year.

Harrison asserts that North Korea could not have financially afforded such items. He is mistaken. North Korea has more than enough funds; indeed, the revenue Pyongyang gets from its illicit activities (currency counterfeiting, narcotics smuggling, and cigarette pirating) alone nets it hundreds of millions of dollars every year.

Although there is a great deal of information in the public domain about North Korea's enrichment activities, two points are particularly worth noting. First, as the news media have reported, Abdul Qadeer Khan (who ran a black-market nuclear supply ring from Pakistan) has confessed to providing North Korea with centrifuge prototypes and blueprints, which enabled Pyongyang to begin its centrifuge enrichment program. North Korea's decision, apparently reached in 2000, to begin acquiring materials in larger quantities for a uranium-enrichment facility with several thousand centrifuges suggests that its R&D-level enrichment endeavors have been successful. Likewise, its procurement of equipment suitable for use in uranium hexafluoride feed and withdrawal systems also points to planning for a uranium-enrichment facility. Pyongyang has yet to address these points and denies the existence of uranium-enrichment activities of any kind.

Second, in April 2003, French, German, and Egyptian authorities intercepted a 22-ton shipment of high-strength aluminum tubes acquired for North Korea by a German firm. In November of that year, a representative from Urenco, the European uranium-enrichment consortium, testified in a German court that the dimensions of those tubes--which were intercepted en route to North Korea--matched the technical requirements for vacuum casings for a Urenco centrifuge. A German newspaper reported that North Korea had attempted to circumvent German, and presumably Chinese, export controls by claiming that the tubes were intended for a Chinese company, Shenyang Aircraft Corporation. It is particularly noteworthy that the specifications for the German aluminum tubes are essentially identical to those used by a Malaysian company in manufacturing outer centrifuge casings for Libya's formerly clandestine gas-centrifuge uranium-enrichment program. Details on those tubes were publicized in the February 2004 press release issued by the Malaysian Inspector-General of Police.

Notwithstanding this accumulation of evidence in the public record, could it still be possible, as Harrison argues, that all of this activity was directed solely at achieving a low-enriched uranium (LEU) capability? Hardly. Harrison's speculation is based on a fundamental misstatement of the technology involved. It is not "much easier" to make LEU than it is to make highly enriched uranium (HEU), as Harrison claims. It typically takes three times as much separative work to enrich uranium from its natural state to 5 percent LEU than it does to enrich LEU to 90 percent HEU. It also makes little economic and technical sense to assert, as Harrison does, that North Korea was planning to produce LEU fuel for the light-water reactors it anticipated getting from the Korean Peninsula Energy Development Organization (KEDO) under the 1994 deal Pyongyang had struck with Washington. KEDO was committed to assisting North Korea in securing a foreign supply of reactor fuel, making it unnecessary for North Korea to undertake the expensive process of domestic LEU production. Moreover, Pyongyang would also have had to construct specialized fuel-fabrication facilities keyed to particular specifications, which North Korea did not possess, for the far-from-complete light-water reactors.

Harrison also argues that North Korea lacks the capability to produce enough electricity for a "multi-centrifuge" uranium-enrichment facility. This is not correct. Unlike the gaseous-diffusion plants the United States constructed during the Manhattan Project, enrichment plants using Urenco-type centrifuges are not significant consumers of electrical power. The same electricity-generating facilities used for normal commercial operations are more than adequate to power gas-centrifuge operations.

Harrison also asserts that the Bush administration has not made a "credible case" to Congress or to U.S. partners in the six-party talks. In fact, the case has been made and is credible. In both open and closed sessions, the intelligence community has briefed Congress on the evidence concerning North Korea's uranium-enrichment program. Deputy Secretary of State Richard Armitage, Undersecretary of State Marc Grossman, Assistant Secretary of State James Kelly, and other officials involved in the negotiating process also have frequently briefed Congress on this issue.

Furthermore, the United States has shared information with all of its partners in the six-party talks concerning North Korea's uranium-enrichment program. And the United States' partners have reciprocated, sharing information they have acquired from their own sources on North Korea's enrichment activities.

Of most concern in Harrison's article is his position that somehow North Korea's uranium-enrichment program is a secondary or tangential issue, so minor that it should be put aside in the interest of negotiating a rollback of North Korea's plutonium-based nuclear weapons program. He discounts the fact that the enrichment program is a clear violation of North Korea's international commitments under the Nonproliferation Treaty (NPT), North Korea's safeguards agreement with the International Atomic Energy Agency (IAEA), the 1994 Agreed Framework, and the 1991 North-South Denuclearization Declaration; he is attempting to make a distinction between "good" cheating and "bad" cheating. Pyongyang's dismal record demonstrates both the centrality of the uranium-enrichment issue to the six-party process and the need to ensure that any solution to the North Korean nuclear issue is thorough and verifiable.

The United States and its partners in the six-party talks are not willing to negotiate over part of North Korea's nuclear-weapons program while leaving Pyongyang in possession of the capability to continue its nuclear weapons effort. To focus solely on the more visible plutonium program would mean turning a blind eye to a parallel program that has the potential to provide North Korea with a covert, steady supply of fissile material for the fabrication of nuclear weapons or export to terrorist groups.

The United States and its partners have been waiting for months for North Korean officials to return to Beijing to engage in serious negotiations and follow up what all other parties had believed to be a productive third round of talks. Washington awaits Pyongyang's formal response to the offer the United States placed on the table last June, as well as the ideas tabled by South Korea and other countries. To start a new relationship, North Korea must forswear its nuclear ambitions, and the six-party talks offer the best opportunity for resolving this issue through peaceful, multilateral diplomacy.

Harrison concludes that the U.S. objective should be, eventually, "to put the North Korean nuclear genie back in the bottle." We respectfully disagree. The U.S. goal should be to remove the nuclear bottle from North Korea entirely. And the time to do so is now.

Mitchell B. Reiss is Vice Provost of International Affairs at the College of William & Mary. From July 2003 to February 2005 he served as Director of Policy Planning at the State Department. Robert L. Gallucci is Dean of the School of Foreign Service at Georgetown University. From September 2000 to February 2005 he served as a member of the CIA's National Security Advisory Panel.


Richard L. Garwin

Selig Harrison argues that "it is much easier to make low-enriched uranium (LEU)--the fuel needed to power light-water plutonium reactors--than it is to make weapons-grade highly enriched uranium (HEU), as Washington has accused Pyongyang of doing." In fact, the centrifuge method is as easily used for producing HEU (nominally 95 percent U-235) as it is for making LEU (typically 4.4 percent U-235 in U-238). The performance of a gas centrifuge is measured by its yield of separative work units (SWU). Each of the centrifuges used in Pakistan or in the European enrichment enterprise, Urenco, may be assumed to produce about 3 SWU per year. The commercial nuclear-fuel market values an SWU at about $100. Technically, the number of SWU that would normally be used to produce a kilogram of U-235 as HEU (about 1.05 kg of HEU) is 232 SWU. The number of SWU that must be invested to make 1 kg of U-235 as LEU (in 22.7 kg of LEU) is about 151 SWU. In both cases one is assumed to start from natural uranium (0.711 percent U-235) and discard depleted uranium with 0.25 percent U-235.

Harrison argues that "a relatively small number of centrifuges is needed to make LEU, but the production of HEU in quantities sufficient for nuclear weapons requires the continuous operation of hundreds--or thousands--of centrifuges over a long period." If one assumes a Urenco centrifuge with a capacity of 3 SWU per year, then the production of LEU containing one metric ton of U-235--enough to replenish for a year a single large reactor producing a million kilowatts of electrical power (the standard-size reactor such as was being built by KEDO in North Korea)--would require 1,000 kg times 151 SWU/kg, or 151,000 SWU. At 3 SWU per year per centrifuge, this would require 151,000 divided by 3, or slightly more than 50,000 centrifuges working for a year. And the next year the plant's output would supply the following year's replacement fuel, and so on. Alternatively, these same 50,000 centrifuges could provide 150,000 divided by 232, or 647 kg of U-235 as HEU. One gun-type bomb using some 60 kg of U-235 as HEU would require 13,920 SWU. Although it is not trivial to make a centrifuge, once that art has been mastered, or once centrifuges have been procured from abroad, it is a much bigger task (by a power of ten) to make a year's worth of LEU to fuel a modern large power reactor than to enrich the 60 kg of HEU for a single gun-type bomb. Making the LEU for a single power reactor would require one year of operation of 50,000 centrifuges; on the other hand, fewer than 5,000 centrifuges would be required to operate for a year to make enough fuel for a gun-type bomb.

Harrison quotes me as estimating that "1,300 high-performance centrifuges would have to operate full time for three years to make the 60 kilograms of fissile material needed for a basic ('gun-type') nuclear weapon." This quote is correct. Three years of 1,300 centrifuges operating at 3 SWU per year would provide 11,700 SWU. The above 13,920 SWU requirement would thus take 3.57 years (or 13,920 divided by 11,700 multiplied by 3), or 3 years, if each of the 1,300 centrifuges can deliver 3.56 SWU per year. If one assumes that an implosion-type weapon uses 20 kg of HEU, then 1,300 centrifuges could produce the requisite HEU in about 14 months.

According to Harrison,

Accomplishing that would require an enormous sustained input of electricity, without fluctuation or interruption. Moreover, the operation of a multi-centrifuge "cascade" requires a high-powered motor with a speed twice that of a MiG-21 jet engine. North Korea cannot produce engines even for its Russian-supplied MiGs, and it has only limited, highly unreliable electricity capabilities. It is therefore unlikely that the country is able at present to build or operate the equipment needed, over a long period, to produce weapons-grade uranium.

This passage gives very much the wrong impression. Each centrifuge is driven by its own built-in motor. A centrifuge's power consumption is something like 100 kilowatt-hours per SWU (about $5 of the $100 price of a commercial SWU). Thus a machine producing 3 SWU per year consumes 300 kWh over a period of 8,766 hours, for an installed power of about 35 watts. This is less than that used by a 40-watt light bulb, and something like that required for a small desk fan. A park of 1,300 centrifuges needs 45 kWh, less power than a small car. There are many small computer centers that demand uninterrupted power, and commercial suppliers sell such systems with multiple small diesel generators for primary power or emergency backup.

Nevertheless, I support Harrison's advocacy of a "plutonium first" approach. If this includes North Korea's rapidly rejoining the NPT, with IAEA inspections, the scope of the enrichment effort would become clear, and the security threat could be brought under control in the context of a broader agreement.

Richard L. Garwin is IBM Fellow Emeritus at the Thomas J. Watson Research Center.

Harrison Replies

If it were as easy as Reiss, Gallucci, and Garwin argue it is to enrich uranium to weapons grade in quantities sufficient for nuclear weapons, and if there were indeed credible evidence that North Korea has a program in place for doing so, one would have expected the Bush administration to put forward this evidence in its response to my article.

Instead, responding to my article on December 10, a State Department spokesman attempted to finesse the issue. Saying only that North Korea has a "uranium enrichment program," he carefully avoided a repetition of earlier accusations that North Korea has a military uranium program capable of producing two or more uranium-based nuclear weapons per year as early as this year. Similarly, Reiss, Gallucci, and Garwin blur the critical distinction between weapons-grade enrichment and lower levels of enrichment that are permitted by the NPT.

I hope that by the time this letter is published, the administration will have redefined its position on the North Korean uranium issue. Presenting credible evidence of a weapons-grade program would help to break the present stalemate in the six-party negotiations, putting North Korea on the defensive. China, South Korea, Japan, and Russia have been openly skeptical of the weapons-grade accusation and critical of a U.S. diplomatic strategy that conditions the start of negotiations on resolving this issue. Putting forward credible evidence would lead to a united diplomatic front in confronting Pyongyang--a united front that the administration has so far been unable to mobilize. Alternatively, if, as I hypothesize, there is not enough evidence to justify accusations of a weapons-grade program, the United States should shift to the "plutonium first" policy that I advocate and that Garwin endorses. The United States could then give priority to getting any plutonium reprocessed so far by North Korea out of the country, while providing for the elimination of any uranium-enrichment facilities at a later stage of a step-by-step denuclearization process.

The central thesis of my article is that the administration exaggerated the intelligence relating to the North Korean uranium-enrichment effort due to its broader agenda: reversing the Clinton policy of engagement with North Korea and, more particularly, abrogating the 1994 Agreed Framework, under which Pyongyang suspended plutonium-based nuclear facilities that could otherwise have produced some 30 nuclear weapons per year. Reiss and Gallucci brush aside this thesis, ignoring the arguments and analysis presented to support it.

As evidence of a bipartisan consensus on the uranium issue, they cite the fact that U.S. intelligence concerns over the possibility of a North Korean enrichment program originated during the Clinton years. Although it closely watched what the North Koreans were up to, however, the Clinton administration sought to head off a possible enrichment program through quiet diplomacy, avoiding a confrontation with Pyongyang that would jeopardize the gains made in controlling the plutonium danger under the Agreed Framework.

By contrast, President Bush openly expressed his desire for regime change in Pyongyang, and from the start, his most influential advisers looked for an excuse to abrogate the 1994 accord. They were (and are) ideologically opposed to providing material incentives that would help to sustain the Kim Jong Il regime in exchange for denuclearization. The result was a paralysis of U.S. North Korea policy until the summer of 2002, when the new intelligence on North Korean enrichment procurement efforts cited by Reiss and Gallucci gave them the desired pretext for abrogating the Agreed Framework. This amounted to throwing the baby out with the bath water, since North Korea predictably retaliated by reprocessing plutonium, an action previously barred under the 1994 accord.

The crux of the Reiss-Gallucci argument is that the new 2002 intelligence justified the CIA assessment that North Korea is making uranium-based nuclear weapons. I am not willing to accept this assessment on faith, considering the ideological agenda driving administration policy and the blatant misuse of intelligence to justify the invasion of Iraq.

In my article, I spelled out numerous specific constraints that would make it difficult for North Korea to enrich uranium to weapons grade, and numerous specific reasons why the evidence leaked by the administration in support of the 2002 assessment should not be taken at face value. None of this analysis is acknowledged or addressed by Reiss and Gallucci. The most important of the constraints that I emphasize is the difficulty that North Korea faces in obtaining sufficient quantities of the many sophisticated components, such as the special grade of maraging steel required for rotors, needed to make centrifuges in quantities sufficient for a large-scale enrichment program. Reiss and Gallucci cite the exposure in April 2003 of a North Korean attempt to import high-strength aluminum tubes as if the attempt itself proves that Pyongyang actually acquired the tubes. I cite the same example to emphasize that the intercept operation worked and to question whether North Korea actually acquired the tubes.

I found a range of views among the experts I consulted concerning just how difficult it would be for North Korea to make and operate the thousands of centrifuges needed for large-scale weapons-grade enrichment. Most of them, however, emphasized that complex metallurgical and chemical techniques are involved in making centrifuges, and that moving from low levels to high levels of enrichment adds to the time involved and thus multiplies the risk of technical problems, such as the corrosion and breakdown of the rotors. This is the point I was seeking to make, and I regret that I confused the issue by incorrectly drawing a comparison between low and high levels of enrichment.

Among the many misrepresentations of my position and misstatements of fact by Reiss and Gallucci, I would like to single out one in the space available. I do not say that "the enrichment program is somehow not central to the nuclear challenge." Nor would my "plutonium first" proposal amount to "leaving Pyongyang in possession of the capability to continue its nuclear weapons effort." On the contrary, I emphasize that "measures to locate and eliminate enrichment facilities that can produce weapons-grade uranium are essential" and that the United States "should insist on stringent terms in a denuclearization process" to locate such facilities if they exist, including the imposition of the NPT's Additional Protocol providing for intrusive inspections.

On one key issue, Reiss and Gallucci appear to concur with my working hypothesis that the Khan network supplied North Korea only with prototypes and blueprints. If this is the case, North Korea would have to import all of the sophisticated components needed to make the large number of centrifuges required for enrichment and to overcome the technical obstacles inherent in this specialized manufacturing process. If Pakistan provided ready-to-use centrifuges in large numbers, the Reiss-Gallucci argument would be much stronger than it is, but so far no evidence of such transfers has surfaced.

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