1991 — The Nuclear Rollback

On July 10, 1991, South Africa signed its accession to the Nuclear Non-Proliferation Treaty, opening its nuclear facilities to international inspectors. Behind the signature lay a secret few had known: in the 1970s and 1980s, the apartheid government had quietly built six nuclear weapons of its own.

President F. W. de Klerk ordered the arsenal destroyed before Foreign Minister Pik Botha signed the treaty. That made South Africa the first, and still the only, nation in history to build nuclear weapons and then voluntarily give them up. Two years later, de Klerk openly admitted the secret program's existence to the watching world.