The election of Ebrahim Raisi as president of Iran brings not just a new face to Iranian politics but also new problems for a Biden administration that hopes to ease tensions with Iran while reining in its nuclear ambitions.

Arguably the most pressing concern for the U.S. is the fate of the Iran nuclear deal, the landmark 2015 agreement that sought to restrain Iran's nuclear ambitions in exchange for a lifting of some sanctions. Since President Donald Trump pulled out of the agreement in 2018, Iran has restarted its nuclear development and has continued to improve its ability to enrich uranium, breaking limits spelled out in the deal.

Raisi himself — a hard-line cleric and judge who has held several roles in Iran's judicial system — won't be responsible for setting foreign policy. In Iran, that's the product of consensus reached among key security and foreign policy institutions and ultimately signed off on by Supreme Leader Ali Khamenei. But the president still plays a major role in how the country's foreign policy plays out.

American negotiators are currently in Vienna, working with their European counterparts to find a way to restore the deal. Many experts believe global powers will be successful in reaching an agreement with Iran, whose supreme leader has already indicated that he's in favor of the nuclear deal.

Raisi has said he'll honor the nuclear deal

And while Raisi has voiced criticism in the past, he made clear during a televised debate with other candidates that he will honor the nuclear deal as an agreement that has been endorsed by the supreme leader. But on Monday, in his first news conference since the election, Raisi pushed back against two other U.S. priorities. He said he would not negotiate over Tehran's ballistic missile program, which the U.S. wants it to stop, or its support of regional militias. Raisi also said he would not agree to a hypothetical meeting with President Biden.

"Whether it was a reformist government, or now that we are going to have a conservative government, I think in both scenarios and cases we would see an administration complying and implementing the deal and complying with the terms," said Abas Aslani, senior research fellow at the Center for Middle East Strategic Studies.

From a political perspective, observers say, this makes sense, because Raisi stands to gain if the sanctions are relaxed and Iran sees domestic economic improvement.

A revamped nuclear deal could be unlikely

But the Biden administration's ambitions go beyond simply restarting the nuclear deal, known formally as the Joint Comprehensive Plan of Action (JCPOA). Secretary of State Antony Blinken has called for a "longer and stronger" deal, which would limit Iran's ability to enrich nuclear material not just for years, but for generations.

But U.S. goals are unlikely to be met under a Raisi presidency, Iran experts tell NPR. "Chances are good for the 2015 nuclear deal to be revived before Raisi takes office in August, but the likelihood of a follow-on agreement is iffy at best," said Barbara Slavin, director of the Future of Iran Initiative at the Atlantic Council.

Iran's current president, Hassan Rouhani, has been seen as a reformist who is open to deals with the U.S. and other Western powers. But Raisi is expected to take a "more nationalistic and hard-line tone," Slavin said.

Instead of seeking any sort of reconciliation with the U.S., Raisi is expected to be more willing to work with China, Russia and Iran's regional allies, Slavin said. Whomever Raisi picks for the Cabinet — and especially foreign minister — will likely be much harder for Washington to deal with than Rouhani's U.S.-educated team.

Any U.S. attempt to add additional conditions to the nuclear deal could be a challenge for negotiators. "This will be very difficult to cope with," Aslani said. Raisi's "conservative administration will be somehow stricter in terms of dealing with the U.S. or European countries when it comes to the region, or when it comes to the military, or defense capability of the country."

Elections in Iran don't usually bring about big changes

Iranian elections have rarely brought about major change in specific Iranian policies, said Suzanne Maloney, director of foreign policy at the Brookings Institution. They're more likely, she said, to set a new tone — either one that's more open to international engagement, as happened after the 1997 election of cleric Mohammad Khatami as president, or one that has "a more provocative, pugnacious stance," as happened in 2005 with the election of the more hard-line Mahmoud Ahmadinejad.

What the Iranian president can do is select a foreign minister and other key Cabinet officials, thereby literally changing the face of Iranian foreign policy and nudging Iran's international engagement toward his own worldview, Maloney said.

"For the most part, I'd expect Iran's approach to the world to remain mostly the same. For example, I see nothing that suggests he would be amenable toward scaling back Iran's massive network of armed militia groups that extends from Lebanon to Yemen," Maloney said. "The main difference will be that the veneer of Iranian goodwill and readiness for engagement with the West will be gone."

There is still mistrust among Iranian hard-liners

Raisi is often described as a "hard-liner" — a term used by Western powers to refer to Iran's "principlist" political faction, which supports the supreme leader and a return to the traditional principles that hark back to the earlier years of the Islamic Republic, said Holly Dagres, senior fellow at the Atlantic Council.

Some trust that might have existed between the U.S. and Iran has already evaporated. "Hard-liners were vehemently against the 2015 nuclear accord from the get-go because they did not trust the West," Dagres said. When Trump withdrew from the multilateral deal in 2018 despite Iran not violating any of its terms, "hard-liners celebrated the decision," she said. "For them, it was their 'I told you so' moment."

Experts say Trump's decision to withdraw played directly into the hands of the supreme leader and other hard-liners, who had warned Iranians that America could never be trusted to uphold its end of the bargain.

"There is a deep, deep mistrust," said Trita Parsi, executive vice president of the Quincy Institute for Responsible Statecraft. Khamenei "believes that his mistrust was completely vindicated by Trump walking out of the deal. He had warned that you cannot trust the Americans: They will betray the agreement, and they will stab you in the back."

Amnesty International wants Raisi investigated

Even if the U.S. can convince Iran to rejoin the nuclear deal, a thornier problem for the international community remains: Raisi's involvement in a "death commission" that secretly executed thousands of political dissidents. Amnesty International is calling for him to be investigated for crimes against humanity.

"I think the bigger problem for the Biden administration and the other parties to the JCPOA will be the optics of extending major sanctions relief to Tehran at a time when it is led by men who are personally complicit in crimes against humanity," said Maloney. "There can be no argument at this time about the prospect for moderation of Iran's regime or its approach to the world, as was the implicit case during the Obama administration."

Alireza Nader, senior fellow at the Foundation for Defense of Democracies, put it more bluntly. "He's a mass murderer," Nader told NPR. "Out of all the past presidents of Iran, all of them have blood on their hands, including Rouhani. But Raisi was responsible for ordering the execution of as many as 8,000 political prisoners in 1988. And he's very proud of that, because he says he was protecting the revolution."

Raisi's demonstrated willingness to "sanction the shedding of blood" is precisely what Khamenei wants at the helm, said Behnam Ben Taleblu, senior fellow at the Foundation for Defense of Democracies. This will help "to keep Iran on a revolutionary trajectory at home and abroad, even after he dies."

Asked about the killings at a news conference on Monday, Raisi stood by his actions.

"I am proud of being a defender of human rights and of people's security and comfort as a prosecutor wherever I was," he said. "All actions I carried out during my office were always in the direction of defending human rights."

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