Fact Sheet

The Iranian Nuclear Threat: Why it Matters

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On July 1, 2019, the International Atomic Energy Agency (IAEA) announced that Iran had exceeded its agreed-to limit on the volume of its stockpile of enriched uranium, putting heightened concerns about an Iranian nuclear weapons program back in the headlines.  Days later, Iran proclaimed it had enriched uranium to about 4.5% purity, again breaching prior agreed to levels.  Since then, Iran has announced numerous other accelerations of its nuclear program that specifically exceed the provisions of the Iran nuclear deal and shorten the time it would take to build a nuclear weapon.


For decades, the United States and the international community have mobilized to prevent a nuclear-armed Iran, believing that nuclear weapons in the hands of the Iranian regime would directly threaten Israel, destabilize the region, and present a security risk to the US, Europe and other allies.  

A nuclear-armed Iran poses a direct threat to America's closest allies in the Middle East. Israel is most at risk as Iran's leaders have repeatedly declared that Israel should "be wiped from the map." America's Arab allies, such as Saudi Arabia, the UAE, Bahrain, and others are deeply alarmed at Iran's aggressive regional policy and would feel increasingly threatened by a nuclear-armed Iran. Indeed, Iran's military posture has led to increases in arms purchases by its neighbors, and a nuclear-armed Iran would likely spark a nuclear arms race in the Middle East that would further destabilize this volatile and vital region.  The US and the international community have a vested interest in maintaining calm in the Middle East.  Even as the United States has recently become a net oil exporter, its economy remains heavily dependent on the stability of international oil markets, which still require the continued steady export of oil from the Middle East.

A nuclear-armed Iran would likely further embolden Iran's aggressive foreign policy, including its deep ongoing involvement in Syria, its attacks against Israel via proxies including Hezbollah, Hamas and other terrorist groups, and its sponsorship of rebel insurgents in Yemen.  Having nuclear weapons would embolden this aggression and would likely result in greater confrontations with the international community. Iran already has a conventional weapons capability to hit U.S. and allied troops stationed in the Middle East and parts of Europe. If Tehran were allowed to develop nuclear weapons, the threat it poses would increase dramatically.

Iran is generally considered the world's leading state sponsor of terrorism, through its financial and operational support for groups such as Hezbollah, Hamas, and others. Iran could even potentially share its nuclear technology and know-how with extremist groups hostile to the United States, Israel and the West.


Iran's nuclear program is clearly intended to develop a nuclear weapons capability. For 18 years, it was kept secret, even though international assistance would have been available to a civilian program. In 2002, Iran's covert program was exposed. Since then, the IAEA has repeatedly said that it cannot consider Iran's nuclear program as entirely civilian. On November 8, 2011 the IAEA released a report stating there is "credible" evidence that "Iran has carried out activities relevant to the development of a nuclear explosive device." Numerous reports since then have underscored Iran’s continuing refusal to address the IAEA’s evidence, which showed “strong indicators of possible nuclear weapon development.”

In 2009, Western intelligence agencies discovered, and Iran admitted to, another secret facility, at Fordow, that is designed for approximately 3,000 centrifuges to enrich uranium. President Barack Obama commented that the "configuration" of the Fordow facility is "not consistent with a peaceful nuclear program." Three thousand centrifuges are sufficient for producing quantities of highly enriched uranium for nuclear weapons, but not for fuel for nuclear power plants.  

In January 2018, Israel’s Mossad intelligence service seized over 50,000 pages of documents and 160 compact discs of data from a Tehran warehouse that housed Iran’s clandestine nuclear archive.  The New York Times determined that the documents “confirmed what inspectors from the International Atomic Energy Agency, in report after report, had suspected: Despite Iranian insistence that its program was for peaceful purposes, the country had worked in the past to systematically assemble everything it needed to produce atomic weapons.”

Despite claims that Iran’s supreme leader once issued a fatwa against the use of nuclear weapons, there are strong reasons to believe that this fatwa may be apocryphal or non-binding.  Meanwhile, Iranian clerical, civilian, and military leaders have repeatedly expressed their intention to wipe Israel off of the map.  


For many years, the major world powers - the United States, China, France, Germany, Russia, and the United Kingdom (known as the "P5+1") - followed a two-track policy:  encouraging Iran to engage in diplomatic negotiations, while imposing increasingly comprehensive sanctions against Iran’s energy and financial sectors. The United Nations Security Council also enacted sanctions against Iran for its nuclear proliferation activity.  Both the United States and Israel promoted the imposition of sanctions as well as the search for a diplomatic resolution, while warning that there would be a time limit for these policies, and that “all options” – including military action - would have to remain on the table. 

On July 14, 2015, the P5+1 announced the finalization of the Joint Comprehensive Plan of Action (JCPOA) agreement with Iran over its nuclear program. The agreement, which emerged after 20 months of negotiations, enacted measures that would significantly scale back Iran’s nuclear program for a period of 10 to 15 years in exchange for the lifting of sanctions against Iran.  That same month, the United Nations Security Council (UNSC) unanimously approved a resolution which endorsed the Iran deal and created a basis for the lifting of UN sanctions against Iran.  There were many supporters of the JCPOA who saw it as the best option for pausing and reversing Iran’s nuclear weapons program.   Critics saw the agreement as flawed, with a “sunset” for restrictions on Iran’s nuclear weapons program and no effective restrictions on Iran’s ballistic missile program or other aggressive policies and behaviors.  (For the specifics on the JCPOA and ADL’s position see here)

On May 8, 2018, President Donald Trump announced that the US would withdraw from the agreement, saying that instead “we will be working with our allies to find a real, comprehensive, and lasting solution to the Iranian nuclear threat.” The US subsequently imposed increasingly strict sanctions against Iranian officials and militant groups associated with its nuclear weapons and ballistic missile programs and other activities.  

As of July 1, 2019, Iran announced (and the IAEA certified) that it had exceeded the JCPOA’s limit on the volume of Iran’s stockpile of enriched uranium, thereby violating the agreement.  This step could considerably decrease the breakout time that it would take for Iran to build a nuclear weapon.  On July 7 Iran also declared it was enriching uranium beyond 3.67% (later announced to be 4.5%), another aggressive action that shortens Iran’s breakout period and is a violation of the JCPOA.  Since then, Iran has continued to announce further infringements against the JCPOA’s main nuclear provisions, including plans to operate more advanced centrifuges and restarting prohibited enrichment activity inside its fortified underground facility at Fordow.

Following the January 2020 US assassination of Iranian Major General Qassem Soleimani, Commander of the Islamic Revolutionary Guard’s Quds Force, Iran announced it will no longer comply with the limits set on uranium enrichment set by the 2015 deal, effectively meaning they could install new centrifuges and move closer to obtaining weapons-grade fuel. In response, the Britain, France and Germany triggered the dispute-settlement mechanism part of the agreement, which could result in the UN Security Council re-imposing some of the sanctions that had been lifted as part of the deal.


Since the 1978-79 revolution which overthrew the monarchy, Iran has been run by a Shia Islamist regime which has violently suppressed internal dissent. Ayatollah Ali Khamenei, the country's powerful Supreme Leader, is the ultimate authority in the Islamic Republic, and it is he who makes the major policy decisions.

There have been periods when it appeared that the Iranian leadership was opting for some relative moderation and reform. This occurred with the election of Mohamed Khatami, considered the "reformist candidate" to the presidency in 1997. While the Khatami government (through 2005) was marked by some moderation in Iran's public stance towards the West, the Supreme Leader, Ayatollah Khamenei, tightly controlled most of the state apparatus. Indeed, Iran's nuclear weapons program also intensified during this period. In June 2013, Hassan Rouhani, a cleric with views considered by some to be more moderate than those of his predecessor, Mahmoud Ahmadinejad, was elected to serve as the country’s next president.  In the election campaign, Rouhani pledged to improve Iran’s economy and pursue an improved relationship with the international community. Mahmoud Ahmadinejad, who was President from 2005-2013, was notorious for his extremist language, including calling for Israel to be “wiped from the earth,” and his promotion of Holocaust denial.   Iran’s egregious human rights abuses, sponsorship of terrorism, and regional aggression have all persisted at high levels under Rouhani’s administration.

Terrorism and Extremism

Iran's regime is a source of extremism and destabilization in the region and around the globe. As noted above, Iran is generally considered to be the leading state sponsor of terrorism, providing financial support and training for organizations such as Hamas, Hezbollah, Islamic Jihad and many Shiite insurgents in Iraq. Iran is responsible for the bombings of the Israeli Embassy (1992) and the Jewish community center (1994) in Buenos Aires, Argentina, which together killed over 100 people and wounded hundreds more. 

Iran’s leaders have repeatedly called for Israel's demise and have propagated vile anti-Semitic tropes including denial of the Holocaust

The Iranian government is also engaged in aggressive foreign policy, backing Syrian President Bashar al-Assad in his government’s brutal campaign against rebel forces and Syrian citizens. Iran has supplied the Assad regime with financial and military support, and its proxy Hezbollah and other associated militia has been a core component in the Syrian fighting force.  Iran also sponsors rebel insurgents in Yemen.

Human Rights Violations

The Iranian regime denies basic freedoms to Iran's citizens, including freedom of speech, freedom of assembly, freedom of religion, and freedom of the press. The rights of women, workers, LGBTQ people, juveniles, religious and ethnic minorities, and political opposition are brutally suppressed.