Sometime in the next week or ten days the winds around the Japanese nuclear reactors that are leaking radiation are going to shift from blowing toward the ocean to blowing southwest, which is to say, towards Tokyo. The Japanese people initially won't panic but the French, the Americans the Scandinavians will. They will monopolize all the planes, trains and aircraft out of the area, at which point the psychological contagion will spread and panic will sweep over Tokyo.
Since there is no good place to put 17 million people there will be no solution. A worldwide depression is not out of the question.
And people still argue there is no over-population problem in the world.