What if Israel suddenly changed course and announced it was prepared to sign the nuclear Non-Proliferation Treaty (NPT) and work toward establishment of a Middle East nuclear-free zone ?

I’m not saying this is in the works. Far from it.

As negotiations between the United States and five other world powers, known as the P5 +1, and Iran head toward some sort of conclusion, it’s apparent that no matter what any agreement contains, there will be a fight in the United States about its merits. And if the agreement survives, the years ahead inevitably will see allegations from all sorts of quarters that one side or the other has violated its terms.

This seemed like an opportune moment to ponder the “What if?” question, which was also triggered by re-reading a section from Israeli columnist Ari Shavit’s 2013 book, “My Promised Land, The Triumph and Tragedy of Israel.”

Shavit briefly described the history of Israel’s nuclear program, tracing it to the beginnings of the newly created state.

Citing the Holocaust and the siege mentality from being surrounded by threatening Arab armies, the Israeli government in the 1950s led by Prime Minister David Ben-Gurion felt “moral justification regarding the right to acquire a nuclear option,” Shavit wrote.

By 1967, through its Dimona complex in the Negev desert, Israel had developed the capability to assemble its first device and in succeeding years produced a nuclear arsenal with land, air and undersea delivery systems, although it does not publicly acknowledge it.

“Dimona gave Israel half a century of relative security,” according to Shavit, but what about now? In the book, he writes: “Israel’s nuclear hegemony in the Middle East is coming to a close. Sooner or later, the Israeli monopoly will be broken.”

He recalls a 2009 conversation with a Dimona veteran whom he does not name but who has since been identified as Yosef Tulipman, who was Dimona’s director general from 1965 to 1973.

Shavit notes that the Iranians have been doing what Israel did, building mini-Dimonas at Natanz (a uranium enrichment plant) and Parchin (a military complex). He adds that if Iran succeeds, Saudi Arabia, Egypt, Turkey and Algeria could be next.

“They all believe that if we [Israel] have a right to our Dimona, they have a right to theirs. And when other Middle Eastern nations exercise their rights, our Dimona will turn from a blessing into a curse,” he writes.

That thought made me realize how different this all would be if Israel, rather than opposing a P5+1 agreement calling for new economic sanctions against Iran and threatening a military attack on Tehran’s nuclear facilities, would put its energy into developing a rational NPT option.

South Africa could be the example.

Its apartheid government — isolated from other countries in part because of its nuclear programs — had developed uranium enrichment in the 1970s. By the end of the 1980s, South Africa had tested and built at least six warheads plus aircraft and missiles to deliver them.

However, South Africa’s newly elected president, F.W. de Klerk, decided in September 1990 to sign the NPT — but only if other African countries did also. Negotiations followed, and in June 1991, when the South African cabinet agreed to sign the treaty, Foreign Minister Roelof “Pik” Botha told a news conference, “This is our way of contributing to the creation of a nuclear weapons-free zone in southern Africa.”

By early September 1991, South Africa’s weapons-grade uranium had been removed from the weapons, melted down and put in storage . The first inspection team from the International Atomic Energy Agency (IAEA) arrived in November 1991 to make sure the safeguards agreement was being followed.

It would take three more years before final destruction of non-nuclear components, including the shredding of design drawings and photos, and an IAEA declaration that South Africa’s nuclear weapons facilities had been dismantled.

Meanwhile, a group of experts under United Nations guidance had begun drafting a treaty creating a nuclear weapon-free zone in Africa. It took years, but in 1996, it was opened for signatures and entered into force in July 2009.

It would take a miracle for Israel’s leaders to go down that path. In April 2010, when President Obama urged all countries, including Israel, to join the NPT, then-Israeli Defense Minister Ehud Barak said there was no pressure for such a step as long as Iran, an NPT signatory, remained a “threat.”

The threat to Israel that generated its bomb — overwhelming Arab armies — no longer exists. The Israel Defense Forces have far more conventional capability than the nation’s neighbors put together, including Iran.

So the best way to remove the Iran nuclear threat is to create a Middle East nuclear-free zone. It has been on the U.N. agenda since the 1960s and the subject of several General Assembly resolutions promoted initially by Egypt and Iran.

It has regularly been discussed at IAEA general conferences that review the NPT every five years. At the 2010 conference, the United States, Russia and Britain agreed to hold a regional conference in 2012 to discuss such a zone. It was postponed, according to a U.S. government announcement, because of a lack of agreement among participants on “acceptable conditions” for the conference. Behind the scenes, it was reported that Israel had not agreed to attend and that Iran, while saying it would appear, added that it would not engage with Israelis should they show up.

In September 2013, Iran’s new president, Hassan Rouhani, appeared before the General Assembly and called on Israel to join the NPT “without any further delay.”

Sadly, it has not and will not happen. What I fear will is one of Shavit’s more depressing conclusions: Dimona’s nuclear weapons success “that allowed Israel to flourish . . . will become the biggest threat facing Israel. It might turn the lives of Israelis into a nightmare.”

For previous Fine Print columns, go to washingtonpost.com/fedpage.