Siegfried Hecker

North Korean officials told an unofficial U.S. delegation last week that many claims about their nuclear program were exaggerated and that they did not have a nuclear warhead or a program to secretly enrich uranium for such a weapon, said sources familiar with the trip. The North Koreans did, however, reiterate their claim to have produced weapons-grade plutonium and showed the delegation their facilities at the Yongbyon nuclear complex and what was purported to be a sample of the plutonium.

An American nuclear expert who visited North Korea's main nuclear facility said Wednesday that he was not allowed to see enough to make a judgment on the country's nuclear weapons capability. Siegfried S. Hecker, former director of the Los Alamos nuclear research laboratory in New Mexico, said the North Koreans "most likely" have the ability at the Yongbyon nuclear site to make plutonium.

The success of last week's concert in Pyongyang by the New York Philharmonic raises the prospect that the United States might start normalizing relations with North Korea, possibly taking the first formal steps before the end of the Bush presidency. Although the musicians and their entourage flew out on Wednesday, more Americans than at any time in the recent past have been visiting a country that President Bush dubbed part of an "axis of evil." Five U.S.

Although fears of Pyongyang responding to South Korea's live-fire drills in the Yellow Sea are diminishing this week, the calm might be short-lived. North Korean leader Kim Jong Il may be planning a provocative act far away from the Northern Limit Line, a sea border drawn by the United Nations at the end of the Korean War. Once again, anonymous "observations of possible test preparation activity" are fueling speculation that North Korea will soon test another nuclear device. Maybe it will ?

BEIJING - The United States and China reacted sharply to the latest torrent of belligerent language from North Korea, which called the U.S. its "archenemy" and said it planned to conduct another nuclear test despite international sanctions. Beijing called for renewed negotiations with North Korea, while Washington promised "additional steps" beyond the expanded sanctions adopted by the United Nations this week. The sanctions notably had the support of China, suggesting growing frustration with its longtime ally.

Three officials of the Los Alamos nuclear weapons lab, including a former director, were disciplined Friday for mishandling an investigation into allegations of Chinese spying. The University of California, which operates the lab for the Energy Department, announced the actions, following a recommendation from the Energy Department. It refused to identify the three, citing privacy concerns.

North Korea said today it was willing to end production and testing of nuclear weapons in return for political and economic concessions from the United States. The regime called its offer "bold and magnanimous" in a statement released over its official news service. Although the proposal was substantially the same as one made last month -- and rejected by the Bush administration -- it appeared to signal that the isolated and impoverished nation is increasingly anxious to cut a deal.

The paradoxes of the Cold Peace are as strange as those of the Cold War. The supreme Cold War paradox, of course, was trillions of dollars spent on each side to prepare for a war that neither side could possibly win. The Cold Peace paradox is billions of dollars spent to prepare for a war that has already been won.

Trying to end months of speculation about whether it really has the bomb, North Korea said Saturday that it had displayed its "nuclear deterrent" for an unofficial U.S. delegation that toured its secretive Yongbyon complex. Members of the private American group confirmed that North Korea had allowed them into the facility that is the heart of the nation's nuclear program, but said they needed time to analyze and report on what they had seen.

A list of five finalists to become director of Lawrence Livermore National Laboratory, one of the nation's two major nuclear weapons research facilities, has been submitted to University of California President David Gardner. The new director will replace Roger Batzel, 66, who is retiring after holding the post since 1971, nearly half the time that the facility has existed. An announcement of the choice could be made as early as March.