History does not repeat itself but it sometimes rhymes. The fact that Barack Obama’s first real presidential trip to Africa coincides with the closing moments of Nelson Mandela’s life could never have been scripted. It is an eerily moving moment. America’s first black president enters the stage just as South Africa’s first black president is taking a bow. No one should doubt Mr Obama when he describes the great freedom fighter as his “personal hero”.

And yet Africans could be forgiven for wondering how long Mr Obama’s renewed interest in Africa will last. Having spent a total of 20 hours on the continent in his first term – on a 2009 stopover in Ghana – Mr Obama’s six-day tour is meant to underline a new phase in US-Africa relations. The age of foreign aid is passing, say US officials. Seven out of 10 of the world’s fastest growing economies are in Africa. Yet it is China – and increasingly Turkey, India and Brazil – that is reaping the new investment opportunities. Now is Mr Obama’s chance to put that to rights.

Mr Obama’s style of doing business, and particularly his diplomacy, does not lend much confidence that his interest will be sustained. With the exception of China, where his engagement has been intensive, Mr Obama’s standard approach is to touch down, give a great speech, proclaim lofty goals, then move on. Such fleetingness might be expected of US presidents, who have real and potential Middle Eastern wars to manage, and a thousand other headaches. That is why they should create clear strategies for others to execute. Alas, there is no clear Obama strategy for Africa. Nor, for that matter, for the Middle East.