Without going into entirely boring detail, the Iranian plan for uranium enrichment depended on a series of high speed centrifuges.

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So in the security realm, again, the Chinese acknowledgment in the statements that -- of the North Korean uranium enrichment program, setting forth a series of conditions that made the Republic of Korea confident enough to go into talks with the North Koreans -- is certain -- I would say one in the security basket.

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The serious business was conducted out of sight, and involved a series of meetings on a new diplomatic effort to persuade the Iranians to halt their uranium-enrichment program. (Iran argues that its enrichment program is for civilian purposes and is legal under the Nuclear Non-Proliferation Treaty.) Secretary of State Rice had been involved with developing a new package of incentives.

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