The international community has welcomed North Korea's decision in recent talks with the U.S. to re-admit nuclear inspectors, mainly because the North Korea will let the IAEA look at a uranium enrichment facility. But experts warn that North Korea has other uranium enrichment plants and is only letting the inspectors in to extract economic advantages, in a repeat of patterns that fooled the international community throughout the last decades.

◆ Tip of the Iceberg

One researcher at a state-run think tank said, "We have to believe that there are more hidden facilities in addition to the uranium enrichment plant is has pledged to open to the inspectors." In other words, North Korea may be seeking to focus international attention on the facility in Yongbyon while secretly running much larger plants elsewhere.

A government official said, "We are aware of the possibility that the Yongbyon facility is just a showcase while the bulk of the operation is elsewhere."

Another official said, "The U.S. and South Korea have an idea where the actual enrichment facilities are, but they aren't talking about it because otherwise North Korea could try to hide them."

In past nuclear negotiations, Pyongyang has never revealed all of its cards. When North Korea was negotiating over a 5 MW reactor in Yongbyon in the early 1990s, it had already extracted a larger amount of plutonium than the U.S. anticipated. When North Korea put on a show of blowing up the cooling tower at its Yongbyon nuclear facility in June of 2008, it had already extracted enough plutonium for several nuclear bombs.

◆ Showcase

Other experts say the facility should be dismantled rather than just inspected. The North's plutonium extraction process can be monitored to prevent it from being used to produce nuclear weapons, but uranium enrichment takes up much less space and facilities can easily be moved out of sight.

One government official said, "North Korea probably accepted IAEA inspectors because it wants to flaunt its uranium-enrichment capabilities, not because it is proposing to denuclearize. If the North shows IAEA inspectors its uranium-enrichment in operation, that proves its nuclear capabilities." That in turn would in the eyes of the regime reduce the threat of a U.S.-led invasion of the kind suffered by fellow dictatorships Iraq and Libya, which had no deterrent weapons.

The North proudly showed the uranium facility to a visiting U.S. nuclear expert in November 2010, evidently to use it as a bargaining chip. The North has tried to boast of its nuclear capabilities whenever it has the opportunity. Former New Mexico governor Bill Richardson and Chinese Vice Minister of Foreign Affairs Daibing Guo, after a visit to the North a month later, said Pyongyang was willing to re-admit IAEA inspectors.

◆ Production Capacity

The U.S. nuclear expert, Siegfried Hecker, in a report after his visit said he was "surprised" to see some 1,000 centrifuges at the Yongbyon uranium-enrichment facility and added it was state-of-the-art equipment. He said North Korean officials told him 2,000 centrifuges had been set up and were in operation, capable of producing up to 40 kg of highly enriched uranium a year.

Nuclear experts say that is difficult to believe since North Korea's power supply is so intermittent as to make it doubtful whether the centrifuges can be safely operated at all.