South Africa and weapons of mass destruction
From the 1960s to the 1990s, South Africa pursued research into weapons of mass destruction, including nuclear, biological, and chemical weapons under the apartheid government. South Africa is one of the ten states to ever acquire a nuclear weapons capability, and the only state to relinquish them.
South Africa's nuclear weapons doctrine was designed for political leverage rather than actual battlefield use, specifically to induce the United States to intervene in any regional conflicts between South Africa and the Soviet Union or its proxies. To achieve a minimum credible deterrence, a total of six nuclear weapons were covertly assembled by the late 1980s.
Before the anticipated changeover to a majority-elected African National Congress–led government in the 1990s, the South African government dismantled all of its nuclear weapons, the first state in the world which voluntarily gave up all nuclear arms it had developed itself.
The country has been a signatory of the Biological Weapons Convention since 1975, the Treaty on the Non-Proliferation of Nuclear Weapons since 1991, and the Chemical Weapons Convention since 1995. In February 2019, South Africa ratified the Treaty on the Prohibition of Nuclear Weapons, becoming the first country to have had nuclear weapons, disarmed them, and gone on to sign the treaty.
Nuclear weapons
The Republic of South Africa's ambitions to develop nuclear weapons began in 1948 after giving commission to South African Atomic Energy Corporation, the forerunner corporation to oversee the nation's uranium mining and industrial trade.In 1957, South Africa reached an understanding with the United States after signing a 50-year collaboration under the U.S.-sanctioned programme, Atoms for Peace. The treaty concluded the South African acquisition of a single nuclear research reactor and an accompanying supply of highly enriched uranium fuel, located in Pelindaba.
Research programs
In 1965, the U.S. subsidiary, the Allis-Chalmers Corporation, delivered the 20 MW research nuclear reactor, SAFARI-1, along with ~90% HEU fuel to South African nuclear authority. In 1967, South Africa decided to pursue plutonium capability and constructed its own reactor, SAFARI-2 reactor also at Pelindaba, that went critical using 606 kg of 2% enriched uranium fuel, and 5.4 tonnes of heavy water, both supplied by the United States.The SAFARI-2 reactor was intended to be moderated by heavy water, fuelled by natural uranium while the reactor's cooling system used molten sodium. In 1969, the project was abandoned by the South African government because the reactor was draining resources from the uranium enrichment program that had begun in 1967. South Africa began to focus on the success of its uranium enrichment programme which was seen by its scientists as easier compared to plutonium.
South Africa was able to mine uranium ore domestically, and used aerodynamic nozzle enrichment techniques to produce weapons-grade material. In 1969, a pair of senior South African scientists met with Sultan Bashiruddin Mahmood, a nuclear engineer from Pakistan based at the University of Birmingham, to conduct studies, research and independent experiments on uranium enrichment.
The South African and Pakistani scientists studied the use of aerodynamic-jet nozzle process to enrich the fuel at the University of Birmingham, later building their national programs in the 1970s.
South Africa gained sufficient experience with nuclear technology to capitalise on the promotion of the U.S. government's Peaceful Nuclear Explosions program. Finally in 1971, South African minister of mines Carel de Wet gave approval of the country's own PNE programme with the publicly stated objective of using PNEs in the mining industry.
The date when the South African PNE programme transformed into a weapons program is a matter of some dispute. The possibility of South Africa collaborating with France and Israel in the development of nuclear weapons was the subject of speculation during the 1970s. In 2010, declassified documents revealed secret meetings between P. W. Botha and Shimon Peres on 31 March 1975 and 30 June 1975, where PW Botha requested nuclear warheads be attached to the Jericho missiles South Africa was purchasing.
Nuclear weapons strategy
Unlike many other countries' nuclear weapons doctrine, South Africa's strategy anticipated no actual battlefield use of nuclear weapons. Although the weapons were intended to be used as a basis for a bluff of its antagonists, South Africa had to be perceived as having the means and resolve to use nuclear weapons in a military conflict. The goal was not to be involved in a nuclear war that South Africa could not survive; the goal was to deter the potential aggression of the country's enemies.South Africa's doctrine for the use of nuclear weapons did not endorse the deployment of the arms in combat, but rather it proposed that the threat of the country's deployment of a nuclear arsenal could be used as political tool.
Such a capability could be used to manipulate other, allied Western powers to assist South Africa against any overwhelming military threat to its sovereignty, such as if Soviet-backed forces were to overrun South African Defence Forces in Angola and then invade South Africa itself. If the South African government found political and military instability in southern Africa to be unmanageable, it might then demonstrate its nuclear capability—such as by conducting an underground nuclear weapons test in the Kalahari Desert.
This would provoke the Soviet Union to escalate its confrontation with the United States until South Africa was constrained, which would mean American intervention to seek an end to the conflict in Angola.
In 1978, the South African Defence Force Chief of Staff for Planning Army Brigadier John Huyser produced a confidential memorandum which outlined potential elements of a nuclear strategy:
- Five to six nuclear weapons would be developed and kept "on the shelf"
- Should the South African Defence Forces find itself in a situation where its conventional forces were facing a catastrophic defeat, information that confirmed South Africa's possession of nuclear weapons would be conveyed to Western countries in a covert manner
- If this did not alleviate the problem, an underground test would be performed to demonstrate South Africa's nuclear capability
- If the threat still persisted, the conduct of an above-ground nuclear weapons test
- Phase 1: Strategic Uncertainty - official denial of nuclear capability
- Phase 2: Covert Condition - nuclear capability covertly revealed, as a means of inducement, persuasion, and coercion
- Phase 3: Overt Deterrent - consideration of the following:
- A battle-ready air-launched weapon for use in an atmospheric demonstration test
- An explosive device for use in an underground demonstration test
- A long-range ballistic missile to threaten strategic use
The "Covert Condition" phase would occur if South African territorial integrity was threatened by the Soviet Union or Soviet-backed forces. South Africa would covertly inform leading Western governments about the existence of its nuclear arsenal and request their assistance to eliminate the military threat it faced.
Finally, the "Overt Deterrent" phase outlined a series of successive escalations that would force the United States and other leading Western countries to intervene on behalf of South Africa to stop whatever war in which the country was involved.
This phase would include the following steps: It would begin with a public announcement of the existence of a nuclear arsenal; foreign experts would be invited to inspect the warheads and their delivery systems, to confirm that they were viable for battlefield use; an underground nuclear test would be conducted; there would be an atmospheric test from an air-launched weapon, hundreds of miles from the coast of South Africa; finally, the country would carry out a nuclear strike on enemy forces that were marshaling for a conventional military attack on South African territory.
Nuclear weapons production
The South African covert nuclear weapons production line and high security storage vaults were located in the Kentron Circle building on the Gerotek vehicle testing facility owned by Armscor on the outskirts of Pretoria. At its secret opening ceremony on 4 May 1981, Prime Minister P.W. Botha described the nuclear deterrent as a "political weapons system" rather than a military one, as it would primarily be used for leverage in international negotiations.South Africa developed a small finite deterrence arsenal of gun-type fission weapons in the 1980s. Six were constructed and another was under construction at the time the program ended.
As the final production model contained a relatively large amount of highly enriched uranium, much effort was expended to ensure the physical safety of the nuclear warheads, with Armscor technicians creating many safety features.
The cornerstone control feature was for each nuclear device to be divided into two subsections, a Front End and a Back End, with the HEU split between the two. This enabled strict security procedures to be enforced, such as storing each subsection in separate vaults with different codes for each door, which were intended to help prevent anyone from having easy access to an entire weapon system.
The fully assembled gun-type devices had enough HEU that they were near critical mass after final assembly. A major safety concern was the Back End propellant could prematurely fire, sending the projectile into the Front End and causing an accidental nuclear explosion. Another potential danger was the projectile accidentally sliding down the barrel, which at a minimum would cause a criticality accident and contaminate the immediate area.
To prevent this, only after the device was armed and ready for use would the barrel rotate to line up the openings correctly. The barrel also contained holes to dissipate the pressure of the propellant firing, thus reducing the speed of the projectile, that were only closed after the weapon was armed and ready for use.
South Africa only produced an operational weapon after Armscor took over production. In 1982, Armscor built the first operational weapon, code-named Hobo and later called Cabot. This device reportedly had a yield of 6 kilotons of TNT. It was eventually disassembled and the warhead reused in a production model bomb. Armscor then built a series of pre-production and production models under the code-name Hamerkop. While Hobo/Cabot were not functional, the Hamerkop series were smart television-guided glide bombs.