Within quick succession, the three giants of northeast Asia have chosen new leaders. Xi Jinping was anointed as China’s heir apparent in November. Shinzo Abe has won a second shot at running Japan. And yesterday, South Koreans elected a new president. If you count Kim Jong-eun, who took over North Korea from his late father last year, that adds up to four new leaders in one of the tensest regions on the planet. The potential for diplomatic brinkmanship – or worse – is high.

As if to mark the possibility of more dangerous times ahead, Mr Kim, the baby-faced 29-year-old installed in Pyongyang, celebrated the regional carnival of elections, selections and dynastic successions the only way he knew how: he let off a long-range rocket. The next day, the Chinese military, now officially under the control of Mr Xi, sent out a surveillance aircraft in what Tokyo said was the first such violation of its airspace since 1958.

At the foot of Asia’s diplomatic garden lies the rotting carcass of unresolved history. Not only does the memory of colonialism and war lurk behind every confrontation. It is embodied in the very leaders now running their respective countries.