Nelson Mandela was released from prison on 2 February 1990. On 26 February F.W. de Klerk ordered the dismantling of a South African nuclear weapons programme which very few people knew existed. At the time the country had six uranium bombs and one more under construction. De Klerk had looked into abandoning the programme a year earlier, but Mandela’s release was plainly instrumental in making it happen. The metallurgist Waldo Stumpf, who had worked on the programme since 1968, was instructed to dismantle the six bombs and to melt down the highly enriched uranium from them and the uncompleted seventh. All the hardware components and the design and manufacturing information were also to be destroyed. The International Atomic Energy Agency was invited to verify the closing down of the programme, which took place over the next two years. South Africa is the only country to have built nuclear weapons and then voluntarily given them up, and this is something else we can thank Mandela for.