Under British rule in 1900, 50 years before apartheid was formally institutionalised in South Africa, most of its features were already in place in the bustling gold-rush city of Johannesburg: Africans were prevented from walking on pavements, had to carry "passes" to work in the city, could not use buses and trains designated for whites, were dreadfully exploited in the mines, and had no political rights. Even as late as the 1980s a British prime minister, Margaret Thatcher, was still siding with apartheid's white oppressors, and denouncing Nelson Mandela as a "terrorist".
Now, with similar high-handed arrogance and contempt for those millions still suffering from the apartheid legacy originally bequeathed by Britain, the government is chopping its £19m aid programme to South Africa – itself a figure that has halved since it peaked at £40m under Labour. (By the way I checked, and South Africa was not consulted, simply informed. When asked why the rush, Justine Greening, the Conservative international development secretary, indicated on Tuesday to Pravin Gordhan, the South African finance minister on a visit to London, that she had to tell the electorate in advance of Thursday's local elections).
Yet three-quarters of the world's poor now live in "middle income" countries like South Africa – where, according to the World Bank, 7 million people are living on under $1.25 a day, and 15 million on under $2 a day. The United Nations reports that more than half of South Africa's children still live in poverty. South Africa may be defined as middle income, but apartheid's legacy is a population still divided between a wealthy – sometimes extremely wealthy – minority and a vast poor majority.
Greening blithely ignores this destitution – deepened by chronic rates of HIV/Aids and TB – in claiming that South Africa has made "enormous progress over the past two decades". It is true that Mandela's African National Congress has delivered electricity, water and sanitation to millions, built more than 3 million new houses, doubled the number at school and is spending more per head on education than almost any other country in the world – some schools financed by British aid.
Nevertheless horrendous levels of black unemployment remain, worsened by apartheid's deliberate policy of ensuring that black people had no skills. A growing population, swelled by some 3 million migrants from Mali to Zimbabwe, means the demand for basic services seems insatiable.
But let's leave aside Britain's historic responsibility for all this. Let's ignore the view that insulting the South African government is small beer compared with its value as a dog whistle, on the eve of the local elections, to Tory voters the party fears are haemorrhaging to Ukip.
Let's leave aside also the raids on Britain's aid budget for defence and other purposes. And how even in the government's own increasingly hard-nosed terms aid is once again becoming a tool of trade rather than an agency for tackling world poverty.
Purely out of self-interest this decision is catastrophic for Britain. South Africa, a key strategic partner, is the sole African member of the important Brics alliance, and is already turning to those countries, away from its traditional European trading links. In turn this threatens the gateway the country provides to vast African markets – where it has close ties of friendship and mutually beneficial trade and investment agreements. It offers a solid base from which companies, including Britain's, can develop their operations across Africa.
And the continent is awakening, with huge growth rates especially compared with sclerotic Europe. Soon seven out of the world's 10 fastest growing economies will be in Africa. If Britain wants to be part of that future, then being a respected partner of South Africa is key, accounting as it does for fully a fifth of total GDP for Africa – despite having a population of just 50 million in a continent of one billion.
Sadly it seems that the era when Britain under Labour could proudly lead the world in cancelling debt, conquering world poverty and establishing a funding mechanism for the millennium development goals, is now over.