Libyan Arms Designs Traced Back to China: Pakistanis Resold Chinese-Provided Plans By Joby Warrick and Peter Slevin.

U.S. intelligence officials concluded years ago that China provided early assistance to Pakistan in building its first nuclear weapon -- assistance that appeared to have ended in the 1980s. Still, weapons experts familiar with the blueprints expressed surprise at what they described as a wholesale transfer of sensitive nuclear technology to another country. Notes included in the package of documents suggest that China continued to mentor Pakistani scientists on the finer points of bomb-building over a period of several years, the officials said.

China's actions "were irresponsible and short-sighted, and raise questions about what else China provided to Pakistan's nuclear program," said David Albright, a nuclear physicist and former U.N. weapons inspector in Iraq. "These documents also raise questions about whether Iran, North Korea and perhaps others received these documents from Pakistanis or their agents."

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"This design would be highly useful to countries such as Iran and North Korea," said Albright, whose Washington-based Institute for Science and International Security has studied the nonconventional weapons programs of both states. The design "appears deliverable by North Korea's Nodong missile, Iran's Shahab-3 missile and ballistic missiles Iraq was pursuing just prior to the 1991 Persian Gulf War," he said.

Such a relatively simple design also might be coveted by terrorist groups who seek nuclear weapons but lack the technical sophistication or infrastructure to build a modern weapon, said one Europe-based weapons expert familiar with the blueprints. While such a bomb would be difficult to deliver by air, "you could drive it away in a pickup truck," the expert said.

The device depicted in the blueprints appears similar to a weapon known to have been tested by China in the 1960s, officials familiar with the documents said. Although of an older design, the bomb is an implosion device that is smaller and more sophisticated than the bombs dropped on Hiroshima and Nagasaki at the end of World War II. Implosion bombs use precision-timed conventional explosives to squeeze a sphere of fissile material and trigger a nuclear chain reaction.

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The evidence of China's transfer of nuclear plans to Pakistan confirms something that U.S. officials have believed since at least the early 1980s. A declassified State Department report on Pakistan's nuclear program written in 1983 concluded that China had "provided assistance" to Pakistan's bomb-making program. "We now believe cooperation has taken place in the area of fissile material production and possibly nuclear device design," the report said.

While the discovery of direct evidence of such cooperation was disturbing, it was noteworthy that China's views on proliferation have changed dramatically since the 1980s, and its leaders now generally cooperate with the United States and other countries in stopping the leaking of sensitive weapons technology, said Jonathan Wolfsthal, a nonproliferation expert at the Carnegie Endowment for International Peace.

Aside from the wholesale transfer of sensitive nuclear technology, there's no real big surprise. The Chinese got a lot of help from the Russkies with that 60's design, although what I've seen gives them credit for remarkable progress. I do wonder if espionage was involved.