How will Iran react to another high-profile assassination?

Last Friday, Iran announced that an important player in its security apparatus had been killed. The target of the attack was Mohsen Fakhrizadeh, a key architect of the country's nuclear weapons program known as Project Amad that ended in 2003 (though elements of it continued for a few years after). Fakhrizadeh's death marks the second time this year that a foreign adversary successfully targeted and killed a major Iranian figure: In January, the United States killed Qassem Suleimani, the commander of the Islamic Revolutionary Guard Corps (IRGC) Quds Force—the unit responsible for designing and implementing much of the country's proxy strategy.

Unlike Suleimani, Fakhrizadeh was not a household name in Iran, much less outside of the country. In fact, until recently, very few photos of Fakhrizadeh had been made public. However, the two men were similar in that they were both senior officers in the IRGC and instrumental to key projects undertaken by the regime. Suleimani expanded and institutionalized Iran's network of nonstate allies and partners that has underpinned its regional strategy, while Fakhrizadeh helped develop the country's nuclear capabilities. Their deaths are symbolic and important blows to Iran, and highlight the country's vulnerability.

After Fakhrizadeh's death, Iranian officials were quick to attribute the attack to one of their chief adversaries: Israel. Jerusalem is also believed to have been behind an explosion at the Natanz nuclear facility—which is currently housing much of the country's uranium enrichment program—this past summer. Israel has a history of targeting the nuclear programs of rivals, including Iran's. It has reportedly assassinated nuclear scientists and conducted cyberattacks in the hopes of setting back Tehran's nuclear advances over the past decade. In 2011, an explosion killed the architect of a third key pillar of Iran's national defense, Hassan Tehrani-Moghaddam, another member of the IRGC, who had helped develop the country's missile program. Israel appeared implicated.

Israeli operations in Iran have also included intelligence gathering. In 2018, Israeli intelligence seized an archive of documents pertaining to Iran's past nuclear weapon work, which shed more light on the activities led by Fakhrizadeh. In fact, while presenting the archive to the public two years ago, Israel's Prime Minister, Benjamin Netanyahu, noted Fakhrizadeh's importance and said to "remember that name."

That Israel has been so successful in conducting such sophisticated operations on Iranian soil—going as far as allegedly hitting a high-profile target identified publicly by Netanyahu in the countryside outside of Tehran—exposes once again the failure of the Iranian regime's internal security and the country's vulnerability to foreign covert action. This presents Iran with a dilemma.

Tehran has an incentive to avoid appearing weak. The country has been hit successfully and repeatedly over the course of 2020, against the backdrop of a pandemic its government has struggled to contain.Tehran has an incentive to avoid appearing weak. The country has been hit successfully and repeatedly over the course of 2020, against the backdrop of a pandemic its government has struggled to contain. In addition to the assassination of two high-profile Iranian figures this year and the Natanz explosion, the United States and Israel appear to have killed al Qaeda's second-in-command, Abu Muhammad al-Masri, in Tehran in August. And the Trump administration continues to expand the list of sanctioned Iranian individuals and entities to exert pressure on Iran, and to complicate the Biden-Harris administration's return to the 2015 nuclear deal—from which Trump withdrew in 2018.
Iran's response to these events has been calculated and calibrated. It has tried to balance two potentially conflicting objectives: avoiding leaving these actions unanswered while refraining from escalating tensions even further, potentially inviting direct military action by the United States. In doing so, Iran has had some embarrassing failures: In January, shortly after Suleimani's death, Iran struck two bases in Iraq that house US forces.

This step was meant to be the first of several, designed to restore deterrence and retaliate for the targeting of one of Iran's most important military commanders. However, the IRGC then accidentally shot down a Ukrainian airliner, killing all 176 passengers and crew onboard and then sought to cover up the error. This tragic incident was deeply embarrassing for the Iranian armed forces, which proved not only incapable of protecting a top military commander but also killed innocent civilians by mistake—perhaps prompting them to exercise some restraint in the months that followed.

But now, with US and Israeli pressure mounting, the Iranian leadership may find it more difficult to sustain its relative restraint. Iran's leaders may view a failure to act as a sign of weakness to adversaries, inviting more covert operations and even an attack on their country. After all, President Donald Trump was reportedly considering conducting an attack on Natanz but was dissuaded from doing so by his advisors. There would also be domestic costs to inaction. The paranoid regime routinely uses force, arbitrarily detains, and tortures individuals it often falsely accuses of spying for adversaries all the while failing to even protect a valued regime insider on its own soil.

Already, some Iranian officials are arguing that the nation must act to retaliate for this attack and deter potential future ones.Already, some Iranian officials are arguing that the nation must act to retaliate for this attack and deter potential future ones. Others are noting that a return to the nuclear deal under these circumstances only further strengthens the hands of its enemies. This is in tension with the other objective harbored by the Iranian system: Preventing further escalation until Jan. 20, 2021, when President-Elect Joe Biden will be sworn in and likely position Washington to return to the nuclear deal in some form. As Henry Rome and I argued in Foreign Policy in September, "Despite extraordinary steps to stabilize the stock market and cover the budget deficit, Iran's economic situation in not sustainable. The regime can almost certainly not risk the return of widespread protests as it falters further."
If Iran were to retaliate for Fakhrizadeh's killing or attempt to restore deterrence, it would almost certainly do so in a deliberate and calibrated manner. It would likely choose options that afford it some level of plausible deniability, as it so often does—including cyber operations and attacks via proxies. However, it still risks provoking a chain reaction. Israel could choose to respond in kind and any such move could further complicate a US return to the nuclear agreement, potentially denying Iran much-needed economic relief. In such a scenario, Iran's so-called strategic patience over the past two years would have been for naught.

Moreover, Trump has proven to be an unpredictable and erratic decision-maker. After Iran-backed Shiite militias in Iraq killed an American in December, he ordered the killing of Suleimani and his Iraqi deputy, Abu Mahdi al-Muhandis. Just months later, in March, these forces killed two US service members and a British soldier. The US response was muted. With just weeks to go before he leaves office, the Iranians could choose to wait for Trump to depart from the White House or to humiliate him on his way out.

Regardless of how Iran decides to retaliate between now and inauguration day, none of its short-term options are risk-free.Regardless of how Iran decides to retaliate between now and inauguration day, none of its short-term options are risk-free. And if such incidents continue to occur in the 50 remaining days of the Trump presidency, they could drag Iran down a path it would prefer not to take. In the medium term, Tehran may become less inclined to negotiate meaningful limits to other areas of concern—including its missile program and support for proxies—which Biden promised on the campaign trail his administration would seek to curtail. In the long term, Iranian leaders may come to the conclusion that their country needs a nuclear weapon to deter adversaries from undertaking such actions in the future regardless of the costs associated with it.

Some Israeli observers contend that taking out Fakhrizadeh will make it harder for Iran to succeed in building a nuclear deterrent. Fakhrizadeh's leadership and knowledge were no doubt critical. But this line of reasoning overestimates the importance of a single individual—regardless of how instrumental and influential he may have once been—in the development of Iran's nuclear program. It also ignores the myriad institutions and organizations involved in Iran's nuclear decision-making and the development of its overt civil nuclear program and covert weapons-related activities. Finally, it misunderstands one of Fakhrizadeh's most important legacies for the regime: helping build its nuclear infrastructure and creating and preserving know-how it could later use should it decide to resume pursuit of the bomb.

Fakhrizadeh's killing on Iranian soil is a significant blow to the government. No matter how Tehran chooses to respond, the second- and third-order effects could be far more significant, leading to a hardened line if and when the country agrees to build on the nuclear deal as envisioned by Biden. More worrying yet, Iran may decide that it should scale up the very activities the Trump administration has sought to prevent with its maximum pressure campaign, including a renewed decision to pursue a nuclear weapon.

Ariane Tabatabai is the Middle East fellow at the German Marshall Fund of the United States and an adjunct senior research fellow at Columbia University. She's the author of No Conquest, No Defeat: Iran's National Security Strategy. Twitter: @ArianeTabatabai

Disclaimer: This article first appeared on Foreign Policy, and is published by special syndication arrangement