Uri Friedman: Why did the South African government, in the mid-1970s, decide to embark on a nuclear-weapons program?

F.W. de Klerk: The main motivation was the expansionist policies of the U.S.S.R. in southern Africa. They were supporting all the [African] liberation movements—they were supplying weapons and training—and it was part of their vision to gain direct or indirect control over most of the countries in southern Africa. They financed the deployment of many thousands of Cuban troops, especially to Angola, and this was interpreted as a threat first by Prime Minister John Vorster, and following upon him P.W. Botha. [The nuclear arsenal] was never intended, I think, to be used. It was a deterrent. Because of apartheid South Africa was becoming more and more isolated in the eyes of the rest of the world. There wouldn’t be, in the case of Russian aggression or invasion, assistance from the international community. It was felt that, if we have nuclear weapons, and if we then would disclose in a crisis that we have [them], it would change the political scenario and the U.S.A. and other [Western] countries might step in and assist South Africa.

Friedman: So you would inform a country like the United States that you had these weapons and therefore they might intervene to stop you from using them against the Soviet Union. Was that the idea?

De Klerk: Exactly. I first became aware of the existence of this program—the full cabinet in South Africa never knew about it—when I became minister of mineral and energy affairs [in the early 1980s]. The bombs were in the making. I never felt comfortable with [the program], but I couldn’t stop it. By the end, when I became president, we had six completed nuclear weapons, and the seventh was halfway done. They were Hiroshima-type weapons.

Friedman: Why did you have misgivings about the program?

De Klerk: I felt that it’s meaningless to use such a bomb in what was essentially a bush war—that it was unspeakable to think that we could destroy a city in one of our neighboring countries in any way whatsoever. From the beginning, in my personal opinion, I regarded it as a rope around our neck.

Friedman: In what sense?

De Klerk: In the sense you have something which you never intend to use, really, which is unspeakable to use, which would be morally indefensible to use.

Friedman: In 1989, when you became president and decided to dismantle the program, what, beyond your personal feelings about nuclear weapons, made you convinced that it was a good decision to dismantle South Africa’s weapons?

De Klerk: With the coming down of the Berlin Wall, and the breakup of the U.S.S.R., the threat of Soviet communist expansionism fell away. Simultaneously, I took initiatives to start a constitutional dialogue and to bring an end to apartheid. A peace accord was signed [in Angola], the Cuban troops were withdrawn, [the southern African state of] Namibia became independent. All those factors brought us to the point where, even if you were a supporter of having nuclear weapons, the rationale for that fell away and the nature of [the] threats changed fundamentally.