On October 1, Iran launched its second direct attack on Israel within six months. Code-named Operation True Promise 2, this assault came in the wake of a series of high-profile assassinations by Israel of key figures in Iran’s network of nonstate allies and proxies, in addition to senior Islamic Revolutionary Guard Corps (IRGC) commanders.

The attack, whose name echoes April’s Operation True Promise, represents another attempt by Iran to restore deterrence in its long-standing conflict with Israel that has moved from the shadows into open confrontation. By demonstrating its willingness and capacity for forceful retaliation, Iran aimed to make Israel reassess the potential costs of any aggression toward Iranian interests. However, the effectiveness of this latest operation in achieving these goals remains uncertain.

What ensues from Tehran’s latest escalation may compel a comprehensive reassessment of its national security strategy. Faced with limited options and a multitude of challenges, Tehran may consider leveraging its status as a threshold nuclear state, raising the specter of potential nuclear weaponization as a means to counter Israel’s perceived military superiority.

The New Equation

For years, Iran’s perceived threat to Israel rested on two primary pillars: its extensive drone and missile arsenal and the capabilities of its proxy forces, particularly Hezbollah in Lebanon. This strategy, known as Iran’s forward defense doctrine, sought to project power and deter adversaries beyond its borders without direct confrontation. Once a cornerstone of Iranian influence in the region, Iran’s forward defense has been under severe strain due to the attrition of its proxies and the apparently limited success of its April strikes in altering Israel’s strategic calculus.

The April attack followed an Israeli strike on an Iranian diplomatic compound in Damascus. Involving hundreds of missiles and drones, the April event marked a significant escalation for Iran—the largest single military operation since the Iran-Iraq War and its first direct strike against Israel from its territory. Afterward, IRGC chief commander Major General Hossein Salami declared, “We have decided to create a new equation . . . from now on, if the Zionist regime attacks our interests, assets, figures, and citizens anywhere, it will be met with a counterattack.” By attacking Israeli targets directly, Iran sought to deter future Israeli aggressions, establish red lines, and ultimately prevent further military casualties like the ones suffered in Damascus.

The first major indication that this strategy had failed came on July 31. First, Israel conducted an airstrike in Beirut’s southern suburbs, targeting senior Hezbollah official Fouad Shukr. Then, just hours after the inauguration of Iranian President Masoud Pezeshkian, Israel assassinated Hamas leader Ismail Haniyeh in a compound on the outskirts of Tehran, a move that took many by surprise and that, similar to the April attack, Iran viewed as an inviolable red line. These attacks occurred amid rising tensions in the region, exacerbated by a Hezbollah rocket attack on July 27 in a Druze village in the Israel-occupied Golan Heights, which killed twelve children and teenagers on a football pitch.

In the weeks that followed, Iranian officials vowed imminent retaliation against Israel. However, Iran, along with Hezbollah, refrained from a response, partly to allow the ongoing ceasefire talks over Gaza to proceed. By doing so, they aimed to achieve through diplomatic means, and at a lower cost, what they could not accomplish through military action: halting Israel’s offensive against the so-called axis of resistance. Moreover, many in Iran seemed to view Israel’s actions as deliberate provocations intended to incite a broader conflict between Tehran and Washington.

But in late August, Hezbollah diverged from Iran’s cautious stance and launched over 300 rockets at targets in Israel, asserting in an initial communiqué that it was a response to Israel’s assassination of Fouad nearly one month prior. Israel then intensified its campaign against Hezbollah.

Further evidence that Iran’s new equation had not materialized came with Israel’s continued decapitation of Hezbollah’s leadership. On September 27, Israeli aircraft killed Hassan Nasrallah, the secretary-general of Hezbollah and arguably the most crucial figure in Iran’s proxy network, as well as Brigadier General Abbas Nilforoushan, the deputy commander of operations for the IRGC. Nasrallah’s assassination was a watershed by itself, but Nilforoushan’s death crossed another red line for Iran. Israel not only dealt a severe blow to Hezbollah but also exposed Iran’s inability to protect its key allies and senior military leadership.

In the immediate aftermath, the rhetoric from Tehran reflected a reluctance to escalate into full-scale war. The Iranian Foreign Ministry’s statement on September 30 declared that Iran would not deploy forces to Lebanon or Gaza. Supreme Leader Ali Khamenei stressed that the axis of resistance would continue without Nasrallah.

Yet Iran found itself in a quandary. Launching a direct military strike against Israel risked igniting an all-out war with a technologically superior adversary and potentially drawing in the United States. Conversely, restraint threatened to erode Iran’s credibility among its allies and adversaries alike, potentially unraveling the carefully cultivated network of proxies central to its regional strategy. While Iran could potentially leverage other members of its axis—including Shia militias in Iraq, Syria, and Yemen—to retaliate against Israel and the United States, the loss of Hezbollah leadership significantly weakened Iran’s regional influence and ability to project power effectively.

Compounding this dilemma was a growing sentiment among Iran’s military leadership that after Lebanon, Syria would be next, followed by Iraq, and ultimately Iran itself. This widespread belief that war was inevitable led many to advocate for preemptive action, reasoning it was better to confront the threat proactively rather than risk being caught unprepared and vulnerable.

At home, Iranian commentators criticized Pezeshkian’s ostensible focus on reform and diplomatic engagement with the West over nuclear issues at the expense of Iran’s closest partners. The argument that a more forceful response to Haniyeh’s assassination might have prevented Nasrallah’s death highlighted the dilemma facing Iranian policymakers. Iran’s perceived threat to Israel, bolstered by its extensive missile arsenal and the capabilities of its proxy forces, had substantially weakened. Iran’s unprecedented missile attack in April proved to be largely ineffective in preventing further Israeli actions with impunity. Meanwhile, Hezbollah, once considered Iran’s most powerful ally, was in disarray and unable to mount a coordinated threat to Israel’s ground invasion of Lebanon.

October 1

On October 1, Iran’s retaliation arrived—but the nature of the strike differed significantly from the April operation.

The April attack involved a diverse arsenal that included ballistic missiles, which are capable of reaching Israeli targets in a few minutes, as well as drones and cruise missiles, which take a few hours. In contrast, the October attack used only ballistic missiles, presumably in part to minimize warning time and reduce the effectiveness of Israeli defenses. It also involved fewer missiles than in April but showcased the Islamic republic’s most advanced systems, including the Fattah-1. Preliminary analyses suggest that the October attacks caused more damage to infrastructure than the April attacks. Even so, the damage to Israel appeared minimal, partly due to Iran’s choices to target primarily military assets and to avoid civilian casualties, though one person was killed in Jericho and two were injured in Tel Aviv.

As it did in April, Iran gave advance diplomatic warning of the attack—but much less this time. Iran reportedly used diplomatic channels to alert the United States of the most recent strike just hours in advance. By contrast, Iran gave a three-day warning to the regional countries hosting U.S. military bases in April.

Iranian officials framed both the April and October operations as proportionate to Israel’s actions, targeting specific military installations used in the Damascus and Tehran attacks. Iran’s initial statements in the aftermath of both emphasized that Iran had no intention of escalating further, signaling an attempt to maintain some level of control over the situation. Both the April and October statements also invoked the legality of the operation under the UN Charter’s right to self-defense, something Iran’s UN mission echoed subsequently.

Response

Iran’s possible strategy to reestablish deterrence, or even to make Israel recalculate its options going forward, may have backfired. Merely launching missiles does not automatically create an effective deterrent. Instead, Israel’s anticipated retaliation is expected to be far more severe than its surgical response in April, when U.S. President Joe Biden urged Israeli Prime Minister Benjamin Netanyahu to “take the win.” Israel is now likely to launch a forceful counterattack that could inflict significant damage on Iranian targets. In a video statement immediately following Tuesday’s attack, Netanyahu vowed to exact reprisals, stating, “Iran made a big mistake tonight—and it will pay for it. The regime in Iran does not understand our determination to defend ourselves and to retaliate against our enemies.”

Israel’s more extreme option, at the moment, would be to strike Iranian nuclear facilities, such as the enrichment site at Natanz, one of the aboveground sites where Iran has produced near-weapons-grade uranium. Another extreme option might include strikes on major oil refineries in Isfahan and Abadan, offshore gas facilities in the Persian Gulf, or key transportation hubs such as the port of Bandar Abbas. These options could cripple Iran’s economy and operational capabilities. More likely, however, Israel might focus on striking military facilities linked to recent attacks or that serve as hubs for Iranian missile production and deployment. Such a response could undermine Iran’s military capability without prompting the broader international outcry that would accompany attacks on nuclear sites.

Assuming Israel does make Iran “pay for” its strike, Tehran’s continued inability to deter Israeli actions effectively or protect its key proxies such as Hezbollah will weaken Iran’s position within the region and raise questions about the long-term viability of its forward defense strategy. Operation True Promise 2, though more advanced than its first iteration, once again demonstrated that Iran’s reliance on missiles—despite their growing sophistication—may not be sufficient to counterbalance Israel’s military capabilities or to engage in a full-scale, long-term war.

Iran’s nuclear program undoubtedly formed a backdrop to the decision to initiate Operation True Promise 2. As a threshold nuclear state, Iran possesses all the key components—fissile material, technical expertise, delivery systems, and facilities—for a nuclear weapon, without having taken the final step toward weaponization. While Iran has consistently maintained that its nuclear program is for peaceful purposes, the potential to leverage this capability as a deterrent against Israeli aggression has undoubtedly been a point of consideration. Moreover, Iranian decisionmakers would not have been blind to the potential Israeli response to attacks against Iran’s nuclear facilities, especially given Tehran’s accumulation of near-weapons-grade uranium and work with advanced centrifuges.

Over the past year, the recent uptick in nuclear rhetoric among Iranian former and current officials reflects a growing interest in maximizing its threshold status as a source of leverage. On the very day of the October attacks, Iran’s Parliament held a debate on its nuclear doctrine, with some lawmakers advocating for the potential development of a nuclear weapon. Such discussions, even if largely rhetorical and driven by hardliners without direct control over nuclear policy, indicate that the nuclear option is becoming an increasingly salient part of the national discourse. By signaling a willingness to reconsider its nuclear posture, Iran may be attempting to send a clear message to its adversaries: If conventional means fail, a nuclear option remains available.

Iran may increasingly view its nuclear potential as a critical component of its broader security strategy. The limited effectiveness of missile strikes and proxy actions against a technologically superior adversary like Israel may push Iranian policymakers to emphasize their nuclear threshold status more openly. This does not necessarily mean an immediate move toward nuclear weaponization, but it does suggest a shift toward leveraging nuclear ambiguity to instill caution in adversaries. For example, Iran implicitly hinted at this potential after the airstrikes, with the IRGC-linked news agency Tasnim running a story claiming the development of “an undisclosed technology to punish Israel.” The very public debate and statements from Iranian officials suggest that Tehran is keenly aware of the need to adapt its strategy—possibly by hinting at nuclear weaponization as a last resort to counterbalance Israel’s military edge.

Iran has not yet made the critical decision to weaponize its nuclear capabilities. For one, full weaponization would be a challenging, yearslong process. Moreover, this extended timeline poses a significant risk for Iran, especially as detection may elicit preemptive strikes from Israel and the United States. Yet, given Iran’s intransigence with the International Atomic Energy Agency and expulsion of inspectors due to nuclear deal gridlock, the ability to detect some of these weaponization activities is even more challenging today. While actual weaponization would come with immense risks, the mere possibility serves as a way for Iran to signal strength at a time when its conventional and proxy-based deterrence is faltering.

The ongoing debate within Iran regarding its regional posture and potential nuclear option highlights the strategic crossroads at which Tehran finds itself. The weakening of its forward defense could push Iranian hardliners toward considering more drastic measures. Though not necessarily indicating an immediate decision to pursue nuclear weapons, it does suggest that Iran may be exploring alternative means of establishing credible deterrence.

The continued asymmetrical tit-for-tat between Iran and Israel risks devolving into a futile cycle of Iranian missile strikes and Israeli retaliations, each exposing Tehran’s military limitations while failing to alter the balance—and potentially driving Iran toward more desperate and unpredictable measures in its quest for credible deterrence.