HONG KONG -- Any day now the mere oscillation of a seismograph needle could precipitate uncertainties and greatly increase tensions: North Korea may become the second East Asian nation to shock the world with an underground nuclear test explosion, just as China did at Lop Nor in 1964.

At the end of April the Bush administration informed the International Atomic Energy Agency in Vienna and several allied nations that an underground test was being prepared by the North Koreans and could take place as early as June. Governments made sure that their seismographs were ready to read any rumbles emanating from northeast North Korea. Prudently, the Americans were not categorical regarding dates.

Washington knows full well that, as ever, North Korea marches to its own unpredictable drumbeat. The current personification of the Kim communist dynastic dictatorship, Kim Jong Il, will decide on the propitious moment for that initial nuclear detonation, perhaps in consultation with one or two North Korean military leaders.