It's not bad that the UK has secured post-Brexit trade deals in Africa; it just doesn't make much sense

So then, six down and only 753 to go. Theresa May’s announcement that the UK has secured its first “post-Brexit trade deal” with six southern African nations should be, even for the sourest of her critics, good news.

Britain will certainly need such deals. The agreement, such as it is, replicates those nations’ existing trade relationships with the EU, rather than breaking any new ground. It has been estimated that there are some 759 such treaties and arrangements with third parties that the UK currently enjoys with various countries through its membership of the EU. Two years after the Brexit referendum, this is as far as the British government has come to renegotiating any of them. It is not so much that Britain is at the back or the front of the queue but rather that its scant international trading efforts haven’t quite made it to joining the queue at all.

Laudable as these African efforts are, the UK’s free trade treaties with the far larger economies of the United States, China, Japan and India, so often mentioned in the rhetoric of buccaneering Brexiteers, remain as yet undrafted. Whether it is chlorinated chicken from America or visas for Indian and Chinese students, the British seem to want their cake and eat it just as much as they do with Europe. Maybe the Africans were more obliging.

Once all part of the British empire, with varying degrees of enthusiasm, and now of the Commonwealth, sentiment counts for relatively little with these independent states: these days money talks, and Germany, China, Japan, South Korea and others often outrank Britain in economic significance. The prime minister’s visit to South Africa, Kenya and Nigeria certainly has an air of commercial bustle about it. It is also true that Africa has long held huge economic potential, as yet still mostly untapped, and some African economies are among the world’s fastest growing.

So there is promise and excitement in this British initiative. Some perspective, though, is required. Nigeria, the largest economy in Africa, has a GDP about the size of Belgium’s. The per capita GDP of a Kenyan is $3,500 or so; that of the poorest of the EU states, Bulgaria, stands at $21,000.

That is not to denigrate the economies of sub-Saharan Africa; there is no reason why they could not reach and exceed income levels seen in the developed world, as happened in east Asia after the Second World War. It is, however, to point out the scale of the challenge for Britain in trying to secure a prosperous future via a boost in trade with faraway poorer nations while making trade with prosperous neighbours more difficult.

The truth, as ever, is that the European Union represents the largest single market in the world, with some of its richest consumers, and, for all its troubles, is growing faster than the UK. It is also, on the whole, less prone to political and economic instability than most of the rest of the world.

Fairer trade with African nations would be a welcome evolution of their current relationship with the west. Trade is a more effective tool than aid. Overseas aid budgets are increasingly geared towards educational and technological help, rather than to subsidise the treasuries of developing economies. The British government now wishes to push this a stage further with the aim, as the prime minister puts it, of overseas aid being spent in the British national interest. This could lead to some imaginative new projects, encouraging private investors and companies to boost development efforts, say through joint ventures and operations led by British-based companies.

This is, broadly, the model followed by the Chinese, although they have much greater financial clout and more of a taste for acquiring land and property than the British have, or least since the end of the colonial era. Ms May seems to have been stung by French ambitions in the continent, in a way redolent of British imperialists in the Edwardian era. If the Africans find themselves courted by both countries, as well as China, it may be turned to their advantage.

There is, one suspects, a message in the prime minister’s rhetoric to her hard right, including the former international development secretary Priti Patel: that British aid will be geared to help British business and, if the choice has to be made, their interests will rank ahead of those of the people of the country concerned. The 0.7 per cent of GDP target for overseas aid may be retained, but the purposes to which it is put will be radically altered, and not always in the interests of the recipients. Britain’s overseas aid effort will, in its way, become another casualty of Brexit.