Kim Jong Un, the Swiss-educated 34-year-old dictator of North Korea, must be pleased with himself. His mixture of nuclear blackmail and Olympic diplomacy has prompted a scramble, as the world’s leaders line up to secure face time with him. Apart from the promise of a meeting with US president Donald Trump, Mr Kim’s greatest win was his visit to Beijing last week, his first overseas trip since becoming supreme leader in late 2011.

In the initial stages of his reign, Beijing preferred to deal with the young Mr Kim’s powerful uncle. But since the younger Mr Kim had his uncle executed in 2013, Sino-North Korean relations descended into a deep freeze.

Last week, after waiting more than six years for an invitation, Mr Kim was finally welcomed to Beijing and granted a lavish audience with President Xi Jinping. China is clearly worried about being sidelined in the process of rapprochement between Washington and Pyongyang.