Then-ANC President Nelson Mandela, left, and South Africa's last apartheid president, Frederik W. de Klerk, shake hands in Oslo after being awarded Nobel Peace Prizes in December 1993. (Gerard Julien/AFP/Getty Images)

When it comes to the fast-approaching summit between President Trump and North Korea's Kim Jong Un and the wish of ending Pyongyang's nuclear weapons program, many hope that a prior model for implementation can be found. But previous U.S.-led attempts to bring about North Korean nuclear disarmament haven't worked — and searching farther afield for successful denuclearization efforts produces shaky results, too.

John Bolton, the White House national security adviser, has publicly suggested that the United States look at Libya, the rogue state that gave up its nuclear program along with other weapons in 2003. That idea drew an angry response from North Korean officials, who appeared aghast that Bolton would suggest Kim follow a path that ultimately saw Libya's Moammar Gaddafi overthrown and killed.

Now, just before the Trump-Kim summit in Singapore, another model has surfaced. According to the Wall Street Journal, U.S. officials have mooted South Africa's path to denuclearization at the end of the Cold War as one example of how North Korea might give up its nukes. It's an interesting idea — but it has its own severe limitations.

South Africa gave up its nuclear weapons program shortly after President Frederik W. de Klerk took office in 1989, just a few years before the end of apartheid and white minority rule in the country. To this day, it remains the only example of a country that willingly relinquished powerful weapons it had developed itself, although some speculate that Israel covertly assisted its nuclear development. Ukraine, Kazakhstan and Belarus also gave up nuclear weapons in the post-Cold War period, but they were giving up Soviet weapons that had remained on their soil.

Some elements of the South African model seem appealing. Among those who think it offers hope is de Klerk himself, who told the Atlantic last year that “the lesson we’ve learned in South Africa, in a wider context apart from nuclear weapons, is that only through negotiation, only if enemies or opponents talk to each other, can peace be achieved, can a new dispensation be agreed upon.”

However, there are real differences between the South African model and any future North Korean denuclearization. For one thing, there are the practical issues: South Africa ultimately gave up six nuclear weapons. U.S. intelligence agencies estimate that North Korea has as many as 60 nuclear warheads, as well as a considerable amount of related technology.

This was an issue with Bolton's Libya comparison, too — Libya's nuclear program was nascent at the time of its dismantlement and had not produced a weapon. North Korea's nuclear program has been underway for decades at this point. “Given the size and scope of North Korea's nuclear and missile programs, verifiable dismantlement will exceed all past precedents,” explained Kelsey Davenport, director of nonproliferation policy at the Arms Control Association.

There are also major differences of motivation in the two cases, in terms of both the wish to acquire nuclear weapons and any desire to get rid of them. South Africa had sought weapons at the height of the Cold War. De Klerk has said the country hoped it could use the knowledge of its nuclear weapons as a warning to the Soviet Union, which was backing a number of liberation movements in Africa at the time.

As the Cold War ended, South Africa faced a significantly different political world — not only internationally, but domestically, as it became clear that apartheid could not survive. De Klerk made a unilateral decision to denuclearize in secret, with little input from the outside world. Some experts have suggested that he made the decision with the idea in mind that white minority rule was coming to an end in South Africa — an idea the former premier himself disputes.

In North Korea, the Kim dynasty began its quest for nuclear weapons in earnest only after the collapse of the Soviet Union, which left the country without a major ally amid unresolved tensions with the United States and South Korea. Its nuclear weapons are a useful bargaining chip for its current geopolitical situation, not a prior one, and there is little concern about them falling into the hands of a succeeding government.

“There is no such motivation for Kim Jong Un,” Alexandra Bell, senior policy director at the Center for Arms Control and Non-proliferation and an Obama-era State Department arms-control expert, said of the idea that de Klerk wanted to keep nuclear weapons out of the hands of a post-apartheid government. “His family has invested decades in the creation of the North Korean nuclear arsenal. He will not give it up easily and certainly not without major security and economic guarantees.”

Although South Africa would go on to join the Nuclear Non-proliferation Treaty and open its sites to inspections by the International Atomic Energy Agency, it still took years for the rest of the world to verify its claims about denuclearization. Bell said that this issue would be more pronounced in any North Korean denuclearization, which would need to be multilateral from the start.

“The international community would never accept the North Koreans' word on denuclearization,” Bell said. “In order for a possible Trump-Kim agreement to work, international inspectors must be allowed access to the North Korean nuclear facilities.”

When it comes to persuading North Korea to give up its nuclear weapons, disarmament experts say there is a wealth of expert knowledge to draw from, as well as smaller lessons from a range of deals in the past. Davenport points to the experience of engaging with nuclear scientists from the former Soviet Union, sealing a test site in Kazakhstan and the verification of missile destruction in Russia.

But the search for a complete model for North Korean disarmament has proved disruptive; the talk of the “Libya model” threatened to derail the Singapore summit before it began. The South Africa model may not be as dangerous, but it doesn't fit, either. “There is no model for a nuclear agreement with North Korea,” Davenport said.

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