We have tried carrots and sticks, aid and sanctions, engagement and isolation. Nothing seems to work.

Month by month, North Korea keeps edging closer to the Bomb. A moment that has been approaching for decades is upon us. A pudgy and petulant man-child, who owes his position to having calmly murdered members of his own family, may soon be able to threaten us with obliteration. Can anything be done, or is the problem, as Vladimir Putin suggests, insoluble?