THE warning shot across South Africa’s bows could not have been clearer. Its response could not have been more foolish. On December 4th Fitch, a rating agency, cut its assessment of South African public debt to just one notch above “junk” (financial jargon for bonds that are deemed risky and so must offer a higher interest rate than “investment-grade” debt). Standard & Poor’s, another agency, implied it was likely to downgrade the country’s rating to junk. Both cited concerns about South Africa’s slow rate of economic growth and its spiralling public debt.

Instead of heeding the warning, President Jacob Zuma compounded the damage by firing Nhlanhla Nene, his respected finance minister, on December 9th. (He said he was moving him to “another strategic position”.) Mr Nene had earned the trust of investors (and the irritation of other ministers) by consistently trying to hold the government to its pledge to limit increases in state spending. He was replaced by David van Rooyen, a backbencher so obscure that one member of the shadow cabinet confessed he had to search for him on Google after the appointment to find out who he was. The rand fell sharply against the dollar, having already slumped to a record low earlier in the week.

Mr Zuma did not give reasons for the change but many South Africans suspected it was because Mr Nene had stood up to powerful allies of the president. Earlier in December he had stymied an attempt by Dudu Myeni, the chairman of perennially loss-making South African Airways, to sign contracts that appeared to make little financial sense. Ms Myeni, who is also the chairman of the Jacob Zuma Foundation, a charity, had wanted to renegotiate contracts to lease jet aircraft from Airbus in a way that might have caused the airline to default on its debts.