American intelligence agencies believe that Iran’s new supreme leader, Ayatollah Mojtaba Khamenei, is far more interested than his father and predecessor in pursuing a nuclear weapon, according to officials briefed on the assessments.
Ayatollah Khamenei’s father, who was killed at the start of the war in an Israeli attack aided by U.S. intelligence, had sworn off developing a nuclear weapon. While American officials long asserted that Iran wanted to be capable of building a nuclear weapon, many believed Ayatollah Ali Khamenei’s hesitancy was genuine.
His successor has never publicly called for Iran to build a nuclear weapon. But U.S. intelligence agencies believe that Mojtaba Khamenei and the harder-line government that emerged after the United States and Israel killed many of Iran’s previous leaders have ambitions to develop advanced nuclear weaponry.
The current government has already worked to assert greater control over the Strait of Hormuz and proved a difficult negotiating partner. If the U.S.-Israeli war has made Tehran more, rather than less, likely to pursue a nuclear weapon, it would amount to one more grave consequence of the killing of the supreme leader and the steps toward regime change the Trump administration initially pursued.
American officials caution that most of the intelligence on Mojtaba Khamenei’s views comes from before the war. He was badly injured in the first part of the war, and American officials said he has limited his communications and public appearances because of his injuries and also because he does not want to be targeted in an airstrike.
The officials assess that he remains in charge of the government but does not have the absolute authority and influence of his father, who ruled for more than 36 years.
The assessment comes as President Trump is weighing whether to intensify the military campaign against Iran. A determination that the supreme leader is potentially open to pursuing a bomb would provide additional justification for an escalation.
While U.S. officials insist Tehran has not made any moves to restart its nuclear program, Iran has taken some steps to preserve its nuclear assets after the U.S. strikes on key facilities last year or during pauses in fighting during the current war.
Iran has moved at least some centrifuges, according to American officials, to a heavily fortified underground complex in central Iran that the United States refers to as Pickaxe Mountain. The Wall Street Journal first reported this week that Israeli intelligence had tracked the movement of the centrifuges.
While such a move could be a first step toward rebuilding enrichment capability, U.S. officials said they believe that for now Iran is more interested in preserving some of its equipment by trying to move it outside the range of American bombs.
In June 2025, Mr. Trump ordered the U.S. military to conduct strikes on three key nuclear facilities. B-2 stealth bombers dropped the largest conventional bombs in the Air Force inventory on two of the sites, Fordo and Natanz. A third site, at Isfahan, was hit with Tomahawk missiles.
Mr. Trump immediately claimed that the military operation had obliterated the facilities, but initial intelligence assessments were far more measured, suggesting the program had only been set back by months.
Iran’s nuclear site at Pickaxe Mountain was not targeted in the attacks last summer. And the facilities there are a far more difficult target for the U.S. military. The underground facilities are buried deep below a mountain, out of the range of the most powerful conventional U.S. bombs, according to multiple American officials.
After assessing the damage at the Fordo nuclear facility, the Iranians learned just how deep the U.S. weapons could penetrate, and are confident that Pickaxe’s even deeper underground halls are safe from conventional aerial attack.
But Iranians remain worried that U.S. forces could mount a commando raid against Pickaxe, potentially using ground forces to enter the site and destroy it from within. U.S. intelligence agencies have reported that Iran has moved ground forces to Pickaxe to deter any ground raid.
Mr. Trump this week threatened to attack the facility, calling it “a possible target for a nice big fat shot right in their front door.”
He also said the United States saw no activity there, a reference, officials said, to the fact that Iran has not restarted nuclear enrichment or other work, despite moving equipment there.
American officials declined to discuss the planning for any attack on the site, and said Mr. Trump has been presented a broad range of options and an array of potential targets. It was foolish, several officials said, to predict what targets Mr. Trump might approve.
Whatever missteps the United States has made in its war with Iran, the damage to the Iranian nuclear facilities, particularly in its strikes last year, succeeded in at least freezing progress on the nuclear program.
The intelligence agencies assessed that the damage would have set back the program by only six months, had the Iranians immediately moved to repair centrifuges or restart enrichment work at other sites. But, American officials said, the Iranians did not immediately dig out all of the facilities or restart enrichment at other locations.
Still, the building blocks of a bomb, most notably Iran’s stockpile of highly enriched uranium, remain intact and accessible to Tehran.
Ali Khamenei had issued a religious order, or fatwa, prohibiting the use of nuclear weapons by Iran, a stance publicly announced to the International Atomic Energy Agency in 2005.
The fatwa had its limits. While it prevented Iran from using a nuclear bomb, it did not block the government from developing its overall program or taking steps toward weaponization. Even after the fatwa was in place, harder-line elements in the Iranian government wanted to be able to quickly develop a nuclear weapon.
But based on public statements and intercepted conversations before the war, American intelligence officials assessed that Mojtaba Khamenei did not share his father’s hesitancy and was interested in pursuing an advanced nuclear weapon.
At the end of the Biden administration, U.S. officials said Iran was looking at ways to develop a cruder nuclear weapon, potentially like the Hiroshima-style bombs, that would be difficult to deliver but would provide something of a deterrent.
The new supreme leader, according to U.S. officials, sees less utility in that type of weapon but appears to support developing the kind of thermonuclear warhead that could eventually be miniaturized and placed on a long-range missile.
In his public statements, Ayatollah Khamenei has vowed to preserve Iran’s nuclear capabilities, but has not spoken directly of a need to obtain a weapon. He distanced himself from an agreement the United States and Iran signed in June that said Iran would not pursue a nuclear weapon. Ayatollah Khamenei said he had allowed the agreement, but did not agree with it as a “matter of principle.”
Rosemary Kelanic, the director of the Middle East program at Defense Priorities, a think tank skeptical of American military intervention, said the war and the announcement this week that the United States may help Saudi Arabia build enrichment facilities make it “significantly more likely” that Iran pursues a nuclear weapon.
“Iran now has a much greater incentive to weaponize to deter future U.S. or Israeli attempts at collapsing the regime or the Iranian state, which means that the war is counterproductive to its own ostensible goals of preventing Iranian proliferation,” she said.
Iranian officials who previously argued in internal debates that only a nuclear weapon could prevent an Israeli or American attack believe their position has been strengthened, U.S. officials have said.
Dustin Volz and Michael Crowley contributed reporting.
