China and Japan’s thriving commercial ties, one of the largest two-way trade relationships in the world, though, have failed to forge a closer political bond. In recent years, the relationship has taken on new and dangerous dimensions for both countries, and for the United States as well, an ally of Japan’s that it has signed a treaty to defend. Far from exorcising memories of the brutal war between them that began in the early 1930s and lasted more than a decade, Japan and China are caught in a downward spiral of distrust and ill will. There has been the occasional thawing of tension and the odd uptick in diplomacy in the seventy years since the end of the war. Men and women of goodwill in both countries have dedicated their careers to improving relations. Most of these efforts, however, have come to naught.