The shared fear of nuclear weapons is so great that even when North Korea declares it has such weapons it's likely that its communist leaders simply hope to capitalize on those fears without ever proving they can actually explode an atomic device.
Indeed, for a nation that's relied on conventional terrorist attacks in the past, this launching of fear - by words alone - toward its presumed adversaries comes easily. It may only be a gambit to win economic concessions from the US, Japan, and South Korea. After all, North Korea's increasingly desperate communist leaders have so botched their economy that they recently had to cut food rations below minimum levels for their starving people.
Still, North Korea crossed a red line in international diplomacy Thursday by announcing that it has nuclear weapons. Leaders in Japan, the US, and elsewhere must now deal with their own public's fears of nuclear weapons and act as if North Korea does possess a viable atomic bomb.
President Bush, in particular, will need to look more aggressive in dealing with this "real threat" while also trying to call the North's probable bluff. Democrats and hawkish Republicans will probably put pressure on him to change his current strategy of using multilateral diplomacy and Chinese pressure to end North Korea's nuclear program.
The Bush administration's real concern, however, appears not to be that the North would use a bomb or even has one, but that it would export nuclear components and bomb-building knowledge to other rogue states and to terrorists.
This month, the White House sent the top National Security Council official on Asia to inform President Hu Jintao of China personally that North Korea was the suspected source of two tons of uranium hexaflouride (which can used to make bomb-grade uranium) shipped to Libya.
The US is right to hold China accountable for letting its ally become a nuclear-weapons exporter. But if Mr. Bush is pushed to change tactics now, it should be to put more pressure on China to curb North Korea's nuclear program through economic means.
China can't afford to let Japan react and go nuclear, or further push the US to set up a missile-defense shield. If Beijing really believes the North has the bomb, it will act now.