U.S. bombers struck dozens of sites across Iraq and Syria on Feb. 2, 2024, to avenge a drone attack that killed three American service members just days earlier.

The retaliatory strikes were the first following a deadly assault on a U.S. base in Jordan that U.S. officials blamed on Iranian-backed militias. Sites associated with Iran’s Islamic Revolutionary Guard Corps (IRGC) were among those hit by American bombs.

The Conversation U.S. turned to American University’s Sara Harmouch and Nakissa Jahanbani at U.S. Military Academy at West Point’s Combating Terrorism Center – both experts on Iran’s relationship with its network of proxies – to explain what the U.S. strikes hoped to achieve and what could happen next.

Who was targeted in the U.S. retaliatory strikes?

The U.S. response extended beyond targeting Al-Muqawama al-Islamiyah fi al-Iraq, or Islamic Resistance in Iraq, the entity claiming responsibility for the drone attack on Jan. 28.

This term, Islamic Resistance in Iraq, does not refer to a single group per se. Rather, it encompasses an umbrella organization, that has since around 2020, integrated various Iran-backed militias in the region.

Iran officially denied any involvement in the Jan. 28 drone strike. But the Islamic Resistance in Iraq is known to be part of the networks of militia groups that Tehran supports with money, weapons and training through the Islamic Revolutionary Guard Corps’ Quds Force.

In recent months, parts of this network of Iran-backed militias have claimed responsibility for more than 150 attacks on bases housing U.S. forces in Syria and Iraq.

As such, the U.S. retaliatory strikes targeted over 85 targets across Iraq and Syria, all associated with Iranian-supported groups and the Islamic Revolutionary Guard Corps.

The U.S. operation’s stated aim is to deter further Iranian-backed aggression. Specifically, in Syria, the U.S. executed several airstrikes, reportedly resulting in the death of at least 18 militia group members and the destruction of dozens of locations in Al-Mayadeen and Deir-ez-Zor, a key stronghold of Iranian-backed forces.

In Iraq, the Popular Mobilization Forces, a state security apparatus comprising groups backed by Iran, reported that U.S. strikes resulted in the deaths of 16 of its members, including both fighters and medics.

The U.S. response was notably more robust than other recent actions against such groups, reflecting an escalation in efforts to counter the threats posed by Iran’s Islamic Revolutionary Guard Corps and its affiliates.

What do we know about the network targeted in the strike?

Initially, the Islamic Resistance in Iraq emerged as a response to foreign military presence and political interventions, especially after the 2003 U.S.-led invasion of Iraq. The Islamic Resistance in Iraq acted as a collective term for pro-Tehran Iraqi militias, allowing them to launch attacks under a single banner. Over time, it evolved to become a front for Iran-backed militias operating beyond Iraq, including those in Syria and Lebanon.

Today, the Islamic Resistance in Iraq operates as a cohesive force rather than as a singular entity. That is to say, as a network its objectives often align with Iran’s goal of preserving its influence across the region, but on a national level – in Iraq, Syria, and Lebanon – the groups have their distinct agendas.

Operating under this one banner of Islamic Resistance, these militias effectively conceal the identities of the actual perpetrators in their operations. This was seen in the deadly Jan. 28, 2024, attack on Tower 22, a U.S. military base in Jordan. Although it is evident that an Iranian-supported militia orchestrated the drone assault, pinpointing the specific faction within this broad coalition is difficult.

This deliberate strategy of obscuring the particular source of attacks hinders direct attribution and poses challenges for countries attempting to identify and retaliate against the precise culprits.

What are the strikes expected to accomplish?

U.S. Central Command said on Feb. 2 that the operation’s aim is to significantly impair the operational capabilities, weaponry and supply networks of the IRGC and its Iranian-backed proxies.

The strikes targeted key assets such as command and control centers, intelligence facilities, storage locations for rockets, missiles, drones, and logistics and munitions facilities. The goal is not only to degrade their current operational infrastructure but also to deter future attacks.

The action followed the discovery of an Iranian-made drone used in an attack on Jordan.

In a broader strategy to counter these groups, the U.S. has also implemented new sanctions against IRGC officers and officials, unsealed criminal charges against individuals involved in selling oil to benefit Hamas and Hezbollah, and conducted cyber attacks against Iran.

How will this affect Iran’s strategy in the region?

Prior to the U.S. response on Feb. 2, Kata’ib Hezbollah, a group linked to Iran, announced a halt in attacks on American targets – a move seen as recognizing the serious implications of the Jordan drone incident.

It is possible that the cessation was the result of pressure from Tehran, though this has been met with skepticism in Washington.

But the development nonetheless speaks to the interplay of influence and autonomy of the so-called Axis of Resistance groups, which oppose U.S. presence in the Middle East and are supported by Iran to varying degrees.

The U.S. airstrikes – combined with sanctions and charges – serve as a multifaceted strategy to deter further aggression from Iran and its proxies. By targeting critical infrastructure such as command and control centers, intelligence operations and weapons storage facilities, the approach aims to undermine Iran’s ability to project power in Syria and Iraq.

The comprehensive and broad nature of the U.S. response signals a robust stance against threats to regional stability and U.S. interests.

The aim is to isolate Iran diplomatically and economically, while squeezing its support for regional proxies. This underscores a commitment by the U.S. to counter Iranian influence that could potentially weaken Tehran’s regional engagement strategies, negotiation positions, and capacity to form alliances.

However, the effectiveness of airstrikes and sanctions in deterring Iranian-backed aggression remains uncertain. Historical trends suggest that similar U.S. actions since the Oct. 7 Hamas assault in Israel, and as far back as 2017, have not completely halted attacks from Iranian-backed groups.

The Biden administration’s approach seeks to navigate this landscape without escalating the conflict, focusing on targeting the financial mechanisms that support Iranian proxies. Yet, the impact and repercussions of such sanctions on Iran and the broader regional dynamics is complex.

In the short term, any direct U.S. retaliation against Iranian interests could heighten regional tensions and exacerbate the cycle of tit-for-tat strikes between the U.S. and Iranian-backed forces, increasing the risk of a broader regional conflict. And given that the attack’s pretext involves the Israel-Hamas war, any U.S. response could indirectly affect the course of that conflict, impacting future diplomatic efforts and the regional balance of power.

Iran’s “forward defense” strategy – focused on addressing threats externally before they become ones within its borders – would suggest that Iran will continue to support proxies through weaponry, funding, and tactical knowledge to reduce the U.S. and its allies’ influence and legitimacy in the region.

This underscores the delicate balance required in responding to Iranian-backed aggression – aiming to safeguard U.S. interests while preventing an escalation into a wider regional confrontation.

Editor’s note: Parts of this story were included in an article published on Jan. 29, 2024.

The views, conclusions, and recommendations in this article are the authors’ own and do not reflect those of the Department of Defense or the U.S. government.

Sara Harmouch does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.