The United Nations, in the words of one diplomat I spoke to, is “broken and disheartened”. So the task for the next Secretary General, Antonio Guterres, is to mend the organisation and give it some heart.

The outgoing incumbent, Ban Ki-moon, has been praised for his soft-spoken persistence in persuading the international community to do more on climate change.

Yet governments and diplomats have long wanted a secretary general with more clout, better English and, above all, stronger leadership.