For a long time, Cyril Ramaphosa was the nearly-man of South African politics. He was Nelson Mandela's preferred successor, but the ANC opted for his rival, Thabo Mbeki, as the second post-apartheid president. Ramaphosa had led South Africa's huge mineworkers' union against the apartheid regime and was the key architect of the much-praised 1996 'rainbow' constitution. He later prospered in business on the back of the first big empowerment deals with...