* 전략안보프로젝트(Strategic Security Project)의 director 마이클 레비라는 사람이 <New Republic>이란 잡지에 쓴 글입니다. (잡지 제목을 보아하니, 미국 공화당 계열의 잡지가 아닌가 추측됩니다만...) 미국이 북한 핵시설을 폭격하는 계획에서 가장 큰 문제는 - 오히려 이미 알려진 영변 지역에 대한 정밀 공격은 방사능 피해가 크지 않을 수도 있지만 - 북한 핵시설이 어디에 있는지 알 수 없는 것이라는 내용을 담고 있습니다. 따라서 외교적인 방식으로 북한핵문제를 해결해야 한다는 주장입니다. 물론 이런 방식의 주장을 옹호해서 글을 소개하는 것은 아니고요, 이런 문제가 언급되는 것을 보면 북한 핵시설 폭격 문제가 기술적인 방식까지 공공연하게 토론되고 있다는 점을 확인할 수 있을 듯하여 올립니다. 개략적인 내용은 다음과 같습니다.

- 많은 분석가들은 북한 핵시설에 대한 정밀 타격은 치명적인 방사능 낙진의 위험을 최소화할 수 있다고 주장한다. 1994년 당시 북한의 핵 프로그램은 단지 영변 지역의 하나의 재처리시설과 세 개의 원자로로 제한되어 있어서, 효과적인 정밀 타격이 가능할 수도 있었다. 그러나 현재 북한이 비밀리에 개발하고 있는 농축우라늄 문제는 그것이 이루어지는 장소가 어디인지 알 수 없기 때문에 정밀 타격이 불가능하다.

- 정밀 타격의 첫 번째 목표는 재처리시설이다. 기술적인 문제는 방사능 낙진이 흩뿌려지는 것인데, 최근 분석에 따르면 방사능 낙진은 북한의 작은 일부 지역에 한정되거나, 대부분은 영변 지역 내부에 봉쇄될 것이라고 한다. 봉쇄된다는 게 무슨 말인가? 재처리시설은 1992년까지 절반 정도 완성되었고, 따라서 미국 정보 당국은 완성된 재처리시설이 어떤 모습인지 추측할 수 있다. 그런데 이 정보에 따르면 주의 깊은 정밀 타격은 피해를 최소화할 수 있다는 것이다. 클린턴 정부의 고위 과학자는 □큰 화재의 발생과 무거운 콘크리트 벽의 붕괴를 막아서 방사능 물질을 파편 속에 가둘 수 있다□고 주장했다. 게다가 이런 방법은 북한이 책물질을 재활용하는 것을 방해하는 보너스 효과도 거둘 수 있다고 주장했다.

- 두 번째 목표는 원자로다. 대부분의 사람은 체르노빌을 기억하기 때문에 파국적인 결과 없이 원자로를 타격을 가하는 방법이 없다고 생각하지만, 반드시 그런 것은 아니다. 북한의 원자로는 천연 우라늄을 사용하는데 이는 물론 유독성 물질이지만 핵물질은 거의 아니다. 원자로가 작동하면서 이 우라늄이 핵분열을 통해 방사능 물질로 전환된다. 북한의 원자로는 재가동되기 전에 우라늄을 채우는데 거의  한 달의 시간이 걸리므로, 위험은 크게 감소된다. 클린턴 정부의 고위 과학자는 □새로운 연료로 매우 오랫동안 가동되기 전에 공격을 감행하면 방사능 물질이 흩뿌려지는 일은 거의 발생하지 않을 것이다□라고 말했다.

- 그런데 진짜 어려움은 2002년 10월 떠오른 농축우라늄 문제다. 먼저 미국은 북한이 언제쯤 핵폭탄을 만들 수 있는 물질을 생산할 수 있는지 모른다. 그리고 그것이 이루어지는 장소가 어디인지 전혀 모른다. 이러한 방식의 핵물질 생산은 전기 소모가 매우 적으며, 또한 그 시설이 차지하는 공간도 매우 작다.

- 또한 영변 지역 외에 재처리 시설이 존재하느냐의 문제도 심각한 의문이다. 레온 시갈에 따르면, 이 문제는 1994년에도 심각한 논쟁을 낳았던 문제다. 재처리시설도 전기 소모가 적고 차지하는 공간이 작기 때문에 찾아내기가 어렵다. 그리고 북한의 터널을 뚫는 기술을 볼 때, 지하에 설치했을 수도 있기 때문에 찾아내는 것은 완전히 불가능하다. 이론적으로 플루토늄 재처리는 그 과정에서 발생하는 가스인 크립톤-85(krypton085)로서 감지가 가능하지만, 일본과 중국의 합법적인 재처리 과정에서도 그 가스가 발생하기 때문에, 그 가능성은 매우 떨어진다. 1994년 위기 당시에 클린턴 정부는 북한 내부에 최소한 12개 이상의 감지기를 설치하려고 시도했지만, 미국의 협상가들은 그것이 너무 공격적이라고 여겨져서 폐기되었다.

- 따라서 군사적 방식의 문제 해결은 큰 어려움을 내재하고 있다.

*	*	*

Off Target

By Michael Levi

Copyright 2003 New Republic, Inc.

The New Republic

March 24, 2003

President Bush caused barely a ripple on March 3 when he apparently shifted America's North Korea policy, remarking to reporters that if America's efforts "don't work diplomatically, they'll have to work militarily." And Bush's words may signify a broader shift: As the Korean crisis has escalated, more and more analysts--including some in the Bush administration--have begun arguing that a U.S. strike on North Korean nuclear targets may be worth the risk.

Many of these analysts believe the United States can strike without prompting a broader war, and they predict that the risks of lethal nuclear fallout from such a precision attack on North Korea's known nuclear sites may be minimal. But they are ignoring one critical problem: In 1994, when North Korea's program was restricted to three nuclear reactors plus the reprocessing of plutonium at Yongbyon, we might have been able to effectively eliminate it through precision strikes. By contrast, the current crisis stems from last October's revelation of North Korea's clandestine uranium-enrichment program, the location of which is unknown. Thus, eliminating Pyongyang's nuclear production capacity through precision bombing is now virtually impossible.

Target number one in a precision strike would be North Korea's reprocessing facility at Yongbyon, where plutonium is extracted from spent nuclear fuel for use in nuclear weapons. The only technological hurdle would be preventing the spread of radioactive fallout. And the good news for any such plan is that massive radioactive fallout is unlikely: A U.S. strike would almost certainly avoid dispersing more than a small fraction of North Korea's radioactive materials, and even this fallout would be largely contained within Yongbyon.

Why would fallout be contained? Inspectors saw the facility when it was roughly half finished in 1992, and American intelligence is thus able to infer what the completed plant looks like. Using this information, a careful strike that minimizes fallout should be possible. As a senior Clinton administration scientist told The New Republic, "There are likely to be ways to destroy the reprocessing plant without causing major fires and using the collapse of the heavy concrete walls to trap most of the radioactive material in the rubble, thus avoiding serious fallout at distances much beyond the Yongbyon site itself." Another knowledgeable source confirms this, adding that the radioactive mess localized to Yongbyon could be a bonus, making it difficult for the North Koreans to return and salvage valuable materials, including spent fuel rods.

The other priority target would be North Korea's nuclear reactor, also at Yongbyon, which, remembering Chernobyl, people tend to assume could not be hit without a major radiological catastrophe. Careful analysis, however, shows the reactor could be struck with little risk of major fallout. North Korea's reactor is fueled with natural uranium, a toxic but barely radioactive material. As the reactor operates, nuclear fission converts the uranium to more radioactive substances; thus, the longer the reactor has been operating, the greater the danger of radiological dispersal. Since North Korea refueled its reactor with natural uranium before restarting it barely a month ago, the risk is greatly reduced. According to the Clinton administration scientist, "A direct attack on the reactor now, before it has operated for very long with its fresh fuel load, might not spread very much high-level radioactive material." According to another knowledgeable source, detailed calculations have shown that even in a worst-case scenario--high winds, a hot graphite fire that would loft radioactive materials high in the air so they might be carried far, and a reactor that had been operating for a long time--there would be no danger beyond North Korea's borders and no immediate radiation sicknesses or fatalities beyond Yongbyon.

It's true, of course, that no attack would be risk-free, even discounting the potential for North Korean retaliation. Small amounts of fallout would be detectable in South Korea, where the p.r. crisis could be far worse for the United States than the public health one. But the larger problem is not that Yongbyon can't be bombed for safety reasons; it's that North Korea contains other nuclear sites that the United States can't bomb because we don't know where they are. Since the United States last considered air strikes, in 1994, our knowledge of North Korea's nuclear landscape has greatly deteriorated. Indeed, the current crisis started in October 2002, when the administration disclosed for the first time its knowledge of North Korea's clandestine uranium-enrichment program. Though it might be more than a year before this program yields enough material for a bomb, our knowledge of the program is so uncertain that we cannot discount the possibility that it will be successful sooner. And, unlike the reprocessing at Yongbyon, the location of the uranium program is entirely unknown. Our evidence of North Korea's enrichment program is its purchasing of centrifuge equipment and associated materials, not satellite imagery of an enrichment plant. The problem is much like in Iraq, where the world can rightly insist that Saddam has chemical weapons without being able to point inspectors to their locations. And, since, like a chemical plant, a centrifuge program consumes little electricity and can be physically small, American intelligence is unlikely to locate it. It is thus almost certain that any precision strike on North Korea's nuclear facilities will leave some of its uranium-enrichment program intact.

And hidden enrichment activity is not our only blind spot. In Disarming Strangers, Leon V. Sigal recounts that the possible presence of undetected plutonium-reprocessing facilities beyond Yongbyon was a crucial point of debate among American military planners in 1994. Today, North Korea is even more likely than in 1994 to have covert reprocessing facilities, potentially making a strike on Yongbyon even less comprehensive and, thus, less useful. Like enrichment plants, reprocessing facilities require little physical space or electricity to operate and are therefore very hard to detect. We have minimal ability to monitor their construction above ground, and the North Koreans, master tunnelers, may well have built underground, making detection all but impossible. In theory, plutonium reprocessing can be detected by mechanically sniffing for krypton-85, a gas produced by reprocessing. But emissions from Japan's and China's legitimate reprocessing facilities could drown out those from a covert North Korean program. During the 1994 crisis, some within the Clinton administration tried to rectify this by pushing for the emplacement of at least a dozen krypton-85 detectors inside North Korea. But such intrusive verification was deemed by American negotiators to be too offensive to the North Koreans, and the detector idea was scrapped, meaning that today the same uncertainty over covert facilities persists.

It would be nice if President Bush's view of the military option--if America's efforts "don't work diplomatically, they'll have to work militarily"--were accurate. But no amount of wishing will change the facts on the ground, and those facts dictate that what might be possible diplomatically--complete denuclearization of North Korea--is impossible militarily short of occupying the North. In 1994, military action, though unpalatable, was a genuine alternative for achieving the same objective sought by diplomacy. Unfortunately, it no longer is