Iran's Nuclear Threat in the Biden Era Israel's Response Options

Key Findings:

In June 2023, Brigadier General Oren Setter, the outgoing head of the Israeli Defense Forces’ (IDF) Strategy Directorate, warned about Iran’s nuclear progress and revealed that Iran was just two weeks away from achieving nuclear breakout capacity — meaning it could produce weapons-grade uranium in a matter of days. Setter projected that Iran could develop a nuclear missile warhead within two years. This assessment echoed the concerns of U.S. General Mark Milley, who had earlier testified to Congress about the rapid timeline for Iran to amass sufficient fissile material for a nuclear weapon. Although Iran has not yet officially crossed the threshold into being a nuclear-armed state, its proximity to that status presents critical challenges for Israel and other regional actors. One of Israel’s key concerns is that Iran could covertly transition to becoming an "unannounced nuclear state," creating significant intelligence difficulties and increasing the risk of a nuclear arms race in the Middle East. This situation could push countries like Saudi Arabia to seek their own nuclear capabilities, further destabilizing the region.

Some analysts hold Israeli Prime Minister Benjamin Netanyahu partly responsible for this scenario, linking his support for former U.S. President Donald Trump’s 2018 withdrawal from the Joint Comprehensive Plan of Action (JCPOA) to Iran’s unchecked advancement of its nuclear program. With the U.S. abandoning the nuclear deal, Iran faced fewer diplomatic constraints, allowing it to advance its nuclear capabilities without the oversight mechanisms established by the JCPOA. This development highlights Israel’s need to reassess its strategic approach in confronting Iran’s status as a nuclear threshold state. Israel’s concerns extend beyond the immediate threat of a nuclear-armed Iran; it also fears that a nuclear-capable Iran could exert greater regional influence. This is already evident in Iran’s improving relations with key regional powers like Saudi Arabia and Syria. Furthermore, Iran’s nuclear capabilities could constrain Israel’s conventional military operations, particularly its ongoing efforts in Syria and Lebanon aimed at countering Iranian influence and Hezbollah’s military buildup.

In response to these challenges, Israel faces three main strategic options, which could be pursued either individually or in combination.

Option I: Attempts to Roll Back Iran’s Nuclear Program. Israel could seek to reverse or delay Iran’s nuclear progress through a combination of diplomatic and military strategies, including diplomacy, sabotage, or direct military action.

(1) Reviving Diplomacy: Israel could push for a diplomatic solution, urging the Biden administration to rebuild an international coalition similar to the one that imposed severe sanctions on Iran between 2011 and 2015, which ultimately led to negotiations over its nuclear program. However, Netanyahu’s previous opposition to diplomacy weakens his credibility in leading such efforts, and the current global geopolitical environment complicates the feasibility of renewing UN sanctions on Iran. The U.S. is now focused on more modest talks aimed at preventing Iran from expanding its nuclear capabilities, rather than reversing them. Even if successful, these talks would not restore the extended breakout times provided by the JCPOA.

(2) Enhanced Sabotage: Israel could intensify its covert operations, including sabotage and cyberattacks targeting Iranian nuclear facilities, as well as assassinations of nuclear scientists. Mossad, Israel’s intelligence agency, has a history of such operations, and its current head, David Barnea, has vowed to prevent Iran from obtaining nuclear weapons. However, the effectiveness of these measures in significantly delaying Iran’s nuclear progress remains uncertain. Moreover, escalated sabotage could provoke Iran to accelerate its nuclear activities, as was the case in 2021 when Iran enriched uranium to 60% following an Israeli attack on its Natanz facility.

(3) Military Strikes: A direct military strike against Iran’s nuclear infrastructure is the most aggressive option but also the most complex and risky. Unlike previous Israeli operations targeting Iraq’s Osirak reactor in 1981 and Syria’s nuclear site in 2007, Iran’s nuclear program is dispersed across multiple fortified locations. A successful military campaign would likely require multiple sorties over an extended period. In addition, Iran’s retaliatory capabilities, particularly through Hezbollah’s rocket arsenal, present a far greater threat to Israel than either Iraq or Syria did. An Israeli strike could also endanger U.S. personnel in the Persian Gulf, complicating coordination between U.S. and Israeli leadership. Moreover, Israel’s internal political crisis, marked by widespread protests and threats from IDF reservists to refuse service, adds an unprecedented domestic challenge to any military decision.

Option II: Securing a U.S. Nuclear Umbrella. Israel could seek a formal U.S. nuclear umbrella, which would entail a commitment from the United States to respond to any Iranian nuclear attack on Israel as if it were an attack on the U.S. itself. This guarantee would serve as a deterrent to Iran’s potential nuclear aggression without requiring Israel to overtly shift its own nuclear posture. Israel has historically resisted defense treaties that might constrain its military autonomy, but a specific nuclear guarantee could provide essential security without such limitations.

(1) Focused Deterrence: A U.S. nuclear guarantee would offer Israel assurance against an Iranian nuclear attack, while still allowing it to retain full control over its conventional military operations. This would ensure Israel could continue its covert and conventional operations against Iranian influence, such as in Syria and Lebanon.

(2) Avoiding Overt Nuclear Posture: Such a guarantee could dissuade Israel from making its nuclear arsenal publicly known, a step that Israel has traditionally avoided in order to prevent triggering a regional arms race. An overt Israeli nuclear posture might push countries like Saudi Arabia, Turkey, and Egypt to pursue their own nuclear programs.

(3) U.S. Interests in Offering a Guarantee: For the U.S., providing a nuclear umbrella would help manage the risks posed by Iran’s nuclear ambitions and prevent a dangerous scenario where both Iran and Israel openly declare nuclear capabilities, potentially destabilizing the Middle East.

Arab states such as Egypt, Jordan, the UAE, and Bahrain might quietly support a U.S. nuclear umbrella for Israel. These countries have shifted toward prioritizing stability and economic cooperation in the region, as demonstrated by the Abraham Accords. They might view a U.S. nuclear guarantee as a less destabilizing option than an overt Israeli nuclear posture, and some may even seek similar security guarantees for themselves.

Option III: Enhancing Israeli Nuclear Deterrence. A third option for Israel would involve enhancing its own nuclear deterrence by shifting from its longstanding policy of nuclear ambiguity to a more overt posture. This would involve publicly declaring aspects of Israel’s nuclear strategy, issuing explicit deterrent threats, or even conducting a nuclear test to underscore its capabilities.

(1) Israeli Public Pressure: As Iran nears nuclear threshold status, Israeli public pressure could mount for a more assertive stance on Israel’s nuclear capabilities. Historically, Israel has neither confirmed nor denied its possession of nuclear weapons, but the existential threat posed by a nuclear-capable Iran could push Israeli leaders to clarify their deterrence strategy.

(2) Strategic Benefits: A more explicit nuclear posture could reduce the risks of miscalculation by making Israel’s deterrent capabilities clear to Iran, potentially preventing an escalation that could lead to conflict. It could also influence Iran’s leadership, particularly the Iranian Revolutionary Guard Corps (IRGC), by making them more aware of the severe consequences of any nuclear aggression.

(3) Risks of an Overt Posture: However, moving to an overt nuclear posture could trigger a regional nuclear arms race, with countries like Saudi Arabia, Turkey, and Egypt accelerating their own nuclear programs. This could dramatically increase the risk of nuclear proliferation across the Middle East and destabilize the region further.