For all their shared interests in a peaceful, prosperous and stable East Asia, there are plenty of reasons for Japan and China to be suspicious of one another, from rivalries over regional influence, to China's assertiveness and military build-up, to the role of the US military. The Yasukuni Shrine to Imperial Japan's war dead should not be among them.
By visiting the shrine yesterday - the 67th anniversary of Japan's surrender at the end of the second world war - two ministers in Prime Minister Yoshihiko Noda's cabinet have made a bad move at a troubled time.
Over the years, visiting Yasukuni has never been tradition among ruling Japanese politicians, despite the cryptic persistence of then-prime minister Junichiro Koizumi in repeatedly visiting last decade, flanked by gatherings of ultra-nationalists, underworld figures and young fascist punks. Neither is Yasukuni under government control, nor does it reflect official policy, as some on the mainland believe.
In 1978, Shinto priests included the names of 14 Class-A war criminals, including wartime prime minister General Hideki Tojo, on scrolls honouring Japan's 2.5 million war dead. The priests also maintain the museum next door, where the nationalistic whitewash of wartime atrocities does not reflect official government histories.
It certainly doesn't reflect the sentiment of Noda as he joined the royal family and 6,000 Japanese for silent noon prayers - in a separate ceremony - where he again expressed Japan's "deep regret" at the damage and pain it inflicted, across Asia and beyond, during the war.
Japan and China expended much diplomatic effort to restore relations after Koizumi's visits. Chinese envoys insisted they did not want to interfere in Japanese affairs, but visits to Yasukuni by senior ministers were beyond the pale. Many across the political spectrum had similar concerns.
The two ministers have not helped their government's cause and may have opened a new avenue for attack from nationalists of a very different stripe across the East China Sea.
Alex Lo is on leave