Experts warn that Iran may already have all the technological know-how needed to develop a nuclear bomb, making the leap to weaponization trivial

Iran is facing a precarious situation, with its proxies throughout the region weakening and with US President Donald Trump’s “maximum pressure” policy continuing to escalate. In this position of weakness, Iran’s push for nuclear readiness has become both its central deterrence strategy and its greatest vulnerability.

Rather than crossing the nuclear threshold outright, Tehran has developed nearly every critical component required to produce a weapon, while stopping just short of assembling one. This ambiguous posture gives Iran space for negotiation, allows it to pressure adversaries with threats of finalizing its nuclear capabilities, and helps it maintain strategic leverage, all while avoiding the full diplomatic and military consequences of openly becoming a nuclear state.

The three critical components of a nuclear weapon are fissile material, a functioning warhead design, and a reliable delivery system. Iran has essentially mastered the first and has likely made progress on the second.

“Iran is indeed in what many analysts call a ‘nuclear threshold’ position,” Shahin Modarres, an international security analyst based in Rome, told The Media Line. “The three critical components of a nuclear weapon are fissile material, a functioning warhead design, and a reliable delivery system. Iran has essentially mastered the first and has likely made progress on the second.”

Escalation between Israel and Iran has made the stakes clearer. On April 1, the Israeli military announced that an Israeli airstrike in Beirut had killed Hassan Ali Mahmoud Badir, a member of Hezbollah’s elite Unit 3900 and the Quds Force of the Islamic Revolutionary Guard Corps. According to Israeli intelligence, Badir had been working closely with Hamas to carry out a mass-casualty terror attack that could have killed hundreds of Israelis. That same week, senior Iranian officials issued open threats of nuclear retaliation.

Ali Larijani, a senior adviser to Supreme Leader Ali Khamenei, declared that a US or Israeli strike on Iranian nuclear facilities would “force” Tehran to build a bomb to “defend its security.”  Hard-line parliamentarian Ahmad Naderi added that the US “wouldn’t dare” threaten Iran if it already possessed an atomic bomb.

According to a report by the International Atomic Energy Agency, Iran has enriched uranium to 60% purity, a short technical leap from the 90% required for weapons-grade material, and its stockpiled uranium could, if further refined, be used to build several bombs. The installation of advanced IR-6 centrifuges, especially in hardened underground facilities like Natanz and Fordow, has also dramatically shortened Iran’s time required to produce enough fissile material for a weapon.

“While Iran denies any ongoing weaponization, past intelligence, like the AMAD Plan, shows they’ve experimented with warhead design and explosive testing,” Modarres explained, referring to an Iranian project that launched in 1989 with the alleged goal of creating nuclear weapons. “What’s missing, at least publicly, is the finalization of a deliverable warhead and a clear political decision to assemble one.”

Zoe Levornik, a nuclear policy and security researcher at northern Israel’s Alma Center, said that Iran is “very close” to achieving weapons-grade uranium. “However, it is still missing some of the technical components needed to achieve a nuclear explosion,” she told The Media Line.

Estimates on how long it would take Iran to produce a bomb range from a few weeks to a few months. “Iran is on the verge of becoming a threshold country, able to produce a weapon in a short amount of time,” Levornik said.

Crossing that final threshold would almost certainly trigger a military response from Israel, the United States, or both. Many experts fear that Iran may have already passed the point of no return regardless—not by building a bomb, but by acquiring the full know-how and technology to do so.

Even if it dismantled its facilities and stopped enriching uranium, Iran can always rebuild and develop the bomb if it decides to do so.

“Even if it dismantled its facilities and stopped enriching uranium, Iran can always rebuild and develop the bomb if it decides to do so,” Levornik said. Once a country develops advanced enrichment capabilities, a skilled scientific workforce, and a functioning nuclear infrastructure, especially one designed for civilian use but easily adaptable for military purposes, the barrier to weaponization becomes political, rather than technical.

This reality underscores that Iran is in no rush to build a bomb as a way of achieving strategic leverage. The decision to cross that final line remains entirely in Iranian hands.

Alongside these efforts, Iran has also been developing weapons delivery systems. Iran’s arsenal includes the Shahab-3 and Sejjil missiles, capable of delivering a nuclear payload to Israel and parts of Europe.

“Iran’s missile program is arguably the most advanced in the region outside of Israel,” Modarres said. “The real challenge is miniaturization, designing a nuclear warhead that can survive reentry and still function. Iran doesn’t need bigger missiles, it needs smaller, more sophisticated warheads and reliable reentry vehicles.”

There are also internal divisions over Iran’s nuclear strategy. The IRGC is believed to favor a policy of opacity regarding its nuclear status, while other factions remain more cautious.

The supreme leader has issued fatwas against nuclear weapons, which some consider sincere and others see as political cover. Meanwhile, technocrats and pragmatists fear the isolation that overt nuclearization could bring. But hard-liners have gained ground in recent years.

“There is no monolithic view in Tehran,” Modarres explained. “The supreme leader has issued fatwas against nuclear weapons, which some consider sincere and others see as political cover. Meanwhile, technocrats and pragmatists fear the isolation that overt nuclearization could bring. But hard-liners have gained ground in recent years.”

Russia and China, while officially opposed to Iranian nuclear weapons, often shield Iran on the international stage. “Russia wants to prevent a nuclear Iran, not to please the West, but to preserve its own dominance in the region,” Modarres noted. “But it also benefits from Iran being a thorn in America’s side, so it plays both ends. China, meanwhile, wants energy stability. It doesn’t want a nuclear crisis that could spike oil prices or provoke US intervention.”

“If Iran crosses the threshold and is perceived to have a bomb within reach, it will almost certainly trigger a cascade,” Modarres warned. “Saudi Arabia has already hinted at matching Iran, and Turkey and Egypt may follow.”

Such a chain reaction would undermine the policy of nuclear nonproliferation and would “potentially force Israel into more drastic deterrence postures,” he added.

As Iran solidifies its position on the nuclear threshold, the window for diplomacy appears to be cautiously reopening. Following indirect talks in Rome, both Iranian and US officials reported “very good progress” and a shared intent to begin designing a framework for a new nuclear agreement.

With a third round of negotiations scheduled and Russia playing key facilitative roles, the prospect of a deal that curbs Iran’s weapons potential, while lifting economic sanctions, seems more plausible than it has in years, despite looming threats of military action if diplomacy breaks down.