By Gwynne Dyer

As with most remarriages between the same partners, the participants aren’t exactly starry-eyed. They just figured out that the old deal was better than no deal at all.

News that the obscurely named Joint Comprehensive Plan of Action (JCPOA) is back in force may reach you even before this article does, but the release of Nazanin Zaghari-Ratcliffe last week was a clear signal that the Iran nuclear deal is back in force.

Ms Zaghari-Ratcliffe, a British citizen of Iranian descent, was arrested in Tehran in 2016 while visiting her mother and imprisoned as a spy. She was actually being held hostage in an effort to force the UK to pay the Islamic Republic a very large and very old debt.

Zaghari-Ratcliffe’s situation got much worse when Boris Johnson, then British Foreign Secretary, falsely claimed that she had come to Iran to “train journalists”. (He is famous for not reading her memoirs.) A year later, her five-year-old daughter, Gabriella, was sent back to London to live with her husband, while Nazanin was serving a five-year prison sentence.

Then suddenly on Wednesday she was flying home and another British hostage of Iranian descent was on the same plane. News has leaked that Britain has finally paid its $540million debt after 45 years in lockdown. (The Shah had ordered British tanks before he was overthrown. Britain canceled the order, but kept the money.) So the JCPOA is back.

In the 2015 deal, Iran agreed not to do any work that would bring it closer to building nuclear weapons for 15 years, in exchange for the lifting of international trade sanctions. It was Barack Obama’s big foreign policy success story – which perhaps explains why Donald Trump, seeking to erase all the achievements of America’s first black president, canceled the deal in 2018.

Former Israeli Prime Minister Binyamin Netanyahu claims credit for convincing Trump of this act of vandalism, which may or may not be true, but, in any case, it didn’t actually kill the deal.

The other JCPOA signatories – China, France, Germany, Russia and the UK – promised to try to bring the Americans back, but, in fact, most obeyed the trade sanctions that Trump imposed. unilaterally to Iran. Iran waited a year, then began stepping up its nuclear research every three months, moving closer and closer to military capability.

The JCPOA treaty stipulated that Iran would not enrich uranium to more than 3.67%. Last month it was up to 60%. Trump and Netanyahu were both gone, and senior Israeli and American officials had concluded that the old deal was better than nothing.

President Joe Biden felt the same way, and he was also worried about an impending confrontation with Russia over Ukraine, so last fall he asked his diplomats to stop trying to make additional concessions to the Iranians. Keep it up!

Still with me here? There will be a try.

Things then moved quickly, and at the end of last month Josep Borrell, the European Union’s foreign affairs chief, said that “a final text is basically ready and on the table”. However, he added, “a pause in the Vienna talks is necessary due to external factors.”

External factors were the Russian invasion of Ukraine and subsequent Western sanctions against Russia. Russian Foreign Minister Sergey Lavrov has demanded that Washington pledge not to impose sanctions on any bilateral trade deal between Russia and Iran after the JCPOA comes back into force.

Lavrov didn’t really believe he could get that promise from the United States. He just wanted to block the resurrection of the JCPOA, at least for now, because that would allow Iran to start selling its oil on the international market.

Currently, Iran exports less than a million barrels of crude oil per day, almost all of it to China. It could sell at least another 1.5 million bpd internationally if the sanctions were finally lifted, and that extra supply would certainly bring the price of oil down sharply.

Oil and gas sales are about the last major source of foreign currency for Russia. The benchmark Brent oil price is today at $95 a barrel, already down more than $40 from last month’s panic spike.

The extra Iranian oil could cost it another $20 or $30 a day, further reducing Russia’s revenue and allowing Europe to buy more oil from Iran, not Russia. But it looks like Lavrov failed to extract guarantees, and the JCPOA is definitely coming back. Good.

There are so many moving parts in this deal that it could still fall apart at the last second, of course. But, for now, it looks good, and Nazanin Zaghari-Ratcliffe is already home with his family.