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Wall Street Journal

North Korea Says It Conducted
Successful Nuclear Weapons Test
By EVAN RAMSTAD
October 8, 2006 11:45 p.m.

SEOUL, South Korea -- North Korea declared it successfully tested a nuclear bomb early Monday. In a statement issued by the country's state-run news agency, North Korea said there was no radioactive leakage from the test, indicating it occurred underground.

There were no immediate details about where the test occurred. There was also no immediate confirmation of the test by U.S. and South Korean military and government sources in Seoul.

North Korea said last Tuesday that it planned to test a nuclear bomb "in the future" but didn't set a specific date. The warning drew condemnation from nations around the world.

The United Nations Security Council on Friday approved a strongly worded statement that "deplored" North Korea's assertion that it was planning a nuclear test. A test, the statement said, would "represent a clear threat to international peace and security." The strong wording implied the prospect of international sanctions against the country if a test was carried out.

Military analysts and atomic scientists will try to determine the size of the bomb and details about its construction by looking for the presence of certain chemicals in the atmosphere above and near the Korean peninsula.

A U.S. military "sniffer" plane began flying between Japan and North Korea shortly after the North issued its Oct. 3 statement that it would conduct a nuclear bomb test. Prior to the blast, analysts estimated North Korea was capable of building a nuclear bomb with 10 kilotons to 20 kilotons of explosive capability.

"This is like carpet bombing for months on end, compressed into a single nanosecond," says Jon Wolfsthal, a fellow at the Center for Strategic and International Studies in Washington.

In comparison, the bomb dropped by the U.S. on Nagasaki, Japan, at the end of World War II had 21 kilotons of explosive force. The largest weapons in the U.S. nuclear arsenal today possess more than 1,000 kilotons in force. With the test, North Korea becomes the ninth country in the world to possess nuclear capability. The others are China, France, Great Britain, India, Israel, Pakistan, Russia and the U.S. All but Israel have confirmed they have held tests of nuclear weapons.

China's foreign ministry had no immediate comment in the hours after the reported test, which is likely to put Beijing, North Korea's prime benefactor, in an extremely difficult position. It is also sure to anger the Chinese leadership, which had issued stern warnings to the North not to go ahead with the detonation.

China will be under increased pressure from Washington to use its economic leverage to pressure Pyongyang, something it has been extremely reluctant to do so far. China is North Korea's major supplier of food, energy and consumer goods.

But it has been loath to squeeze the regime of Kim Jong Il, fearing it could precipitate a collapse, leading to refugee flows into China or, more worrisome from a Chinese strategic perspective, to conflict on the peninsula or the absorption of North Korea by U.S. ally South Korea.

Beijing policymakers also worry that North Korea's move to become an unambiguous nuclear state could upset the balance of power in East Asia, encouraging Japan to strengthen its military capabilities.

If North Korea's claims of a nuclear test prove true, Japan would appear to be the most immediately vulnerable to North Korea's nuclear ambitions. It is within range of the North's missiles, as demonstrated in 1998, when one was launched over Japan and into the Pacific Ocean. China is a traditional ally of the North, and Pyongyang sees South Korea as part of the same nation.

However, regardless of what may or may not have happened in North Korea, experts don't expect Japan to move toward developing nuclear weapons of its own. Such a move would have the potential to kick off an arms race in the region and put Japan in even more danger. Instead, Japan would continue to rely on its security treaty with the U.S. for nuclear defense, and boost the scope of this -- as shown by its involvement in the missile defense initiative.

"I don't see the Japanese going nuclear as long as the U.S. [security] guarantee is credible, which it is," says Kenneth Pyle, founding president of the National Bureau of Asian Research in Seattle.

Still, he said if a nuclear North Korea is emerging, it might push Japan to spend more on defense, which it currently limits to 1% of the country's GDP, compared with a little over 4% for both the U.S. and China.

Write to Evan Ramstad at evan.ramstad@wsj.com