Late last month, Britain, France and Germany triggered the “snapback mechanism” on Iran, initiating the process of reinstating UN sanctions on the country for its failure to comply with a 2015 deal designed to thwart its ability to build nuclear weapons.

At the same time, the countries, known as the E3, said they would continue their diplomatic efforts over the next 30 days to reach an arrangement with Iran over its nuclear program.

Israel welcomed the move, but warned that Iran wasn’t about to change course.

The move is “an important step in the diplomatic campaign to counter the Iranian regime’s nuclear ambitions,” said Foreign Minister Gideon Sa’ar, adding that the return of sanctions was “inevitable.”

The deal, known as the Joint Comprehensive Plan of Action (JCPOA), removed harsh international sanctions on Iran in exchange for restricting its ability to produce nuclear material and allowing inspections to monitor its compliance. US President Donald Trump pulled the United States out of the agreement in 2018.

Only two months ago, Israeli and American planes bombarded the key nuclear sites in Iran, setting the program back significantly. After the 12-day campaign, do diplomatic efforts to curtail Iran’s nuclear ambitions still matter? And will the threat of renewed sanctions — or their eventual imposition — have any effect on Iranian behavior?

Ten weeks after Israel’s Operation Rising Lion in June, the state of Iran’s nuclear program remains unclear. Prime Minister Benjamin Netanyahu said that it was set back “by years,” but hasn’t offered additional details or evidence to back up that assessment.

One of the central questions is the fate of the Islamic Republic’s pre-attack stock 400 kilograms of uranium enriched to 60 percent, enough for up to 10 nuclear weapons after an additional stage of enrichment.

US Vice President JD Vance acknowledged the possibility that Iran still has the uranium: “Our goal was to bury the uranium, and I do think the uranium is buried, but our goal was to eliminate the enrichment [program] and eliminate their ability to convert that enriched fuel into a nuclear weapon,” he told Fox News in an interview.

More clarity is unlikely to emerge in the near future.

“Until international atomic energy agency inspectors are able to get back into Iran and determine where Iran’s stockpile of enriched uranium is, determine how many of the centrifuges were destroyed, it’s going to be challenging to assess how quickly Iran could return to the threshold of nuclear weapons,” said Kelsey Davenport, director for Nonproliferation Policy at the Arms Control Association.

Iran’s nuclear program is in a state of “suspended animation,” said Jonathan Ruhe, director of foreign policy at the Jewish Institute for National Security of America. “It likely still retains some basic infrastructure and know-how to try to complete a crude test device, but it also has every reason to think it’d be caught and punished. The key factor in Iran’s nuclear next steps is not technical, but psychological – it’s deterred for now by the fear of being hit again.”

For now, the Iranians seem focused on rehabilitating air defenses and recovering from the Israeli attacks, not on pushing ahead with their nuclear program.

“There is no indication right now that the Iranians are trying to remove highly enriched uranium or to use remaining centrifuges,” said Raz Zimmt, an Iran scholar at the Institute for National Security Studies in Tel Aviv.

“Theoretically, they can at some point move ahead on a covert pathway, but that comes with risks and, for now, is not their direction.”

With Iran’s nuclear program badly damaged, and no indication that Tehran is working on rebuilding it, the European decision to move ahead with snapback sanctions might seem superfluous at this stage.

Throughout the years of efforts to contain Iran’s nuclear program, the Europeans have consistently said that diplomacy is the best way to deal with the challenge. The snapback sanctions, which would expire on October 18, are the last piece of leverage the Europeans have to push Iran back into negotiations, and they aren’t about to let it slip away.

Still, even if the E3 do manage to get talks resumed in earnest, it won’t be over a return to the 2015 deal.

“The JCPOA is dead,” said Davenport. “It’s no longer a viable agreement politically or even technically. So calling for Iran to come back into compliance with its commitments, that’s a non-starter.”

Instead, the E3 is pushing for Iran to let IAEA inspectors resume their work inside the country, and for Tehran to re-engage in serious nuclear talks.

After the US-Israeli operation, the E3 and Washington will be pushing for an even tougher nuclear deal than the JCPOA, with an enhanced inspections regime and limits to weaponization activity.

There are ample reasons for even nuclear hawks to support a diplomatic push.

“If well executed and coordinated, diplomacy might coerce a weakened Iran to meaningfully restrict its nuclear capacity and stop obstructing IAEA inspectors,” said Ruhe. “But the predicates for successful diplomacy are a united US-E3 front and consistent attention from Washington, both of which are missing.”

Though Iran does not seem to be rebuilding its nuclear program now, there is no guarantee it won’t do so in another six months or a few years down the road.

“That’s why it is important that there be some kind of oversight mechanism with boots on the ground,” Zimmt explained.

Without inspectors in Iran, Israel and its Western allies will be fully dependent on intelligence to track any nuclear developments. The capabilities and penetration of Israeli and US intelligence are impressive and were on full display during operations Rising Lion and the US’s Midnight Hammer. Yet all intelligence has limits, and Iran will learn and implement lessons from the painful surprises it experienced in June.

Though the reimposition of sanctions might sound threatening, they won’t necessarily budge Iran’s leadership.

With his return to office, US President Donald Trump reimposed his sanctions on Iran, instructing the US Treasury secretary to impose “maximum economic pressure” on Iran, including sanctions and enforcement mechanisms on those violating existing sanctions. He also directed the Treasury and State Department to implement a campaign aimed at “driving Iran’s oil exports to zero.”

The European Union also reimposed some sanctions over the past year.

With those sanctions in effect once again, the economic benefit that Iran enjoys from the lifting of sanctions under the JCPOA is already limited.

Moreover, Moscow and Beijing publicly oppose the snapback sanctions. Last week, the Chinese, Russian, and Iranian foreign ministers issued a letter saying that the move by Britain, France, and Germany to automatically restore the sanctions was “legally and procedurally flawed.”

The two major powers are unlikely to stop trading with Iran, further blunting the effect of sanctions.

China’s purchase of Iranian oil is the most important element of this relationship. Beijing accounts for 90% of Iran’s oil exports, which make up over one-third of Iran’s budget sources.

Despite those challenges, there is potential to make the sanctions bite, argued Ruhe.

The sanctions can be “as damaging as America, Europe, and others are willing to make it,” he said. “The UN sanctions are incredibly strong on paper, effectively prohibiting Iran’s entire nuclear and ballistic missiles programs, cutting it off from the global arms trade, and mandating compliance from every UN member. But enforcement requires concerted US and European diplomatic leadership and coordination. Israel’s military credibility offers helpful leverage for the US and Europe here.”

Iran has issued vague threats in the wake of the E3 announcement, and it does have some cards to play.

Tehran could shut the door on IAEA inspectors, announce the renewal of limited nuclear activities, or threaten US allies and international shipping in the Middle East.

Most worryingly, Iran could withdraw from the nuclear Non-Proliferation Treaty altogether.

“There is a real risk that even if [Iranian President Masoud]  Pezeshkian does not want to leave the NPT, he’ll be forced into it, either by the [parliament] or the Supreme Leader,” said Davenport. “And there would be serious ripple effects, both in terms of putting the US, Israel, and Iran back on the path to conflict, but also for the broader Iran proliferation regime if Iran follows through on the threat to withdraw from the NPT.”

All of the options in front of Iran come with significant risks. Hovering over any retaliatory measures by Tehran is the possibility of another Israeli or US attack. The path to diplomacy remains open, but so does the road to war.