As fears of an American recession unfold, stockmarkets all over the world have been jittery. The strikes have been the wildest of all in Japan. On August fifth the Topix plunged by 12% in its worst efficiency since 1987; the yen had climbed from its weakest level in 37 years. The subsequent day, shares swung again, rising by 9%, as buyers snapped up shares that had plunged in worth. The sharp strikes carry implications not only for Japanese buyers and companies. The nation’s monetary heft signifies that they may turn into a supply of additional volatility in nervous world markets.