North Korea dangers lurk whatever nuclear test result

By Paul Eckert, Asia Correspondent - Analysis

WASHINGTON (Reuters) - The jury is still out on the size and success of North Korea's nuclear test, but the May 25 blast could give any proliferation plans Pyongyang might have a marketing boost no matter how it measures up.

Even nuclear experts who see the explosion as militarily insignificant paint scenarios ranging from future sets of nuclear and missile tests by North Korea to exports of dangerous technology to full-blown cooperation with Iran.

Last week, a U.S. official said initial American testing was "inconclusive" in confirming whether a nuclear device was detonated and more tests were needed.

The Vienna-based Comprehensive Test Ban Treaty Organization said the blast North Korea asserts was its second nuclear test since 2006 resembled both an explosion and an earthquake. But it said absolute proof required detection of radioactive particles and noble gases, expected this week at the earliest.

U.S. nuclear experts are cautious about the results, pending the release of more data, but unanimous about the proliferation concerns raised by the North Korean test.

Based on the U.S. Geological Survey's report of a 4.7 magnitude quake near the test site, the North Korean explosion yield was in the range of two to four kilotons, estimated Stanford University nuclear scientist Siegfried Hecker.

"This test appears to be about five times more powerful than the 2006 test. Thus, the test was more successful," he said, cautioning that the degree of success depended on what yield North Korea was aiming for.

"Now, they likely have sufficient information to have confidence in a simple nuclear arsenal," added Hecker.