Take a handful of uninhabited islets roughly equidistant between Okinawa and Taiwan. Add a Chinese trawler captain, determined to fish in what he regards as Chinese waters. Then mix in a Japanese patrol boat defending Tokyo's control of the islands. Finally, leave the Chinese fisherman to stew (preferably in a non-stick Japanese jail) for two weeks. Voilà. You have just created a diplomatic row to traumatise much of Asia and rattle even Washington.

The immediate cause of alarm is Beijing's rough-house tactics following the captain's arrest in waters near the disputed Senkaku islands, known as Diaoyu islands in Chinese. Not only did Beijing insist on the captain's immediate release, a demand to which Tokyo eventually capitulated. It also escalated the dispute. It arrested four Japanese nationals; blocked exports of rare earths used by Japanese electronics companies; cancelled diplomatic exchanges; and allowed anti-Japanese demonstrators to pour on to Chinese streets. (It even canned the tour of SMAP, a Japanese boy-band.) Even the release of the captain did not mollify Beijing, which demanded an apology and compensation.

The underlying concerns go deeper still. Diplomats detect a pattern of more assertive - some say aggressive - Chinese behaviour. If Japan, with its still-powerful economy and sophisticated defence force, cannot stand up to Beijing, what hope for the many smaller countries that have territorial disputes with China? Most of these have lain dormant for decades. Beijing has hitherto been happy to put them on the back-burner, favouring a charm offensive aimed at convincing neighbours that its rise poses no threat.

David Fuller's view This is a concern but not a shot has been fired, so far. Both China and Japan know that "to jaw-jaw is always better than to war-war", as Winston Churchill said.