North Korea's statement that it already has nuclear weapons is most likely an exercise in diplomatic brinkmanship aimed at drawing the United States into direct dialogue. But if the statement is true, the security environment surrounding Japan and Northeast Asia will undergo fundamental change.
The U.S. has reacted calmly, given earlier reports from its intelligence agencies that the North Koreans probably possess one or two atomic bombs. In the absence of conclusive evidence, U.S. officials have stressed the need for a careful analysis of the North Korean comment.
What if the North already has nuclear weapons? Of course, that would be a blatant violation of the Nuclear Nonproliferation Treaty, or NPT, and a reckless challenge to the international order. It would also be an outright rejection of the plan for a nuclear-free Korean Peninsula -- a plan supported by China and Russia, which Pyongyang regards as friends.