Perhaps the least noted and most astonishing aspect of the entire diplomatic process involving North Korea during the past few years has been the almost complete inability of four of the world's strongest military and economic powers - the United States, China, Russia and Japan, which include three nuclear weapons states and three members of the UN Security Council - to shape the strategic environment in Northeast Asia. They have proven thoroughly incapable of preventing an impoverished, dysfunctional country from consistently endangering the peace and stability of the world's most economically dynamic region. This has been nothing less than a collective failure. Only when the other parties to the Six-Party Talks undertake a fundamental reassessment of the costs and benefits of their current policies will there be a chance to rein in, never mind reverse, Pyongyang's nuclear-weapons programme.