On June 13, the Israeli Air Force, in coordination with its intelligence community, launched a significant campaign targeting Iran’s nuclear facilities, ballistic missile program, and broader military and civilian infrastructure. Following several days of political and diplomatic pressure from Israel and its allies, the United States entered the conflict.

On June 21, the U.S. launched Operation Midnight Hammer, the largest deployment of B-2 bombers in a single strike. Seven B-2 bombers dropped six GBU-57 Massive Ordnance Penetrators (MOPs), also known as “bunker busters,” on Fordow, Iran’s heavily fortified nuclear enrichment facility buried deep inside a mountain. U.S. bombs also hit targets at Natanz and Isfahan.

Since then, the precision of the strikes, the rapid pace of escalation, and speculation about a possible Iranian retaliation against the United States have dominated headlines. Amid this high-stakes confrontation, however, Iran’s regional partners and proxy forces have so far remained conspicuously absent from the battlefield.

Since the Islamic Republic’s founding in 1979, Tehran has worked steadily to build a regional network of allied non-state actors. Early outreach to Iraqi Shi’ite groups, including the influential al-Sadr family, and the establishment of Hezbollah in Lebanon in early 1980s marked the beginning of this effort. Iran also forged close ties with the Assad regime in Syria, both under Hafez al-Assad and his son Bashar, forming a regional front against common adversaries: Saddam Hussein’s Iraq, Israel, and later, Western influence.

This network, referred to as the “Axis of Resistance,” got a major boost with the U.S. invasion of Iraq in 2003, which deposed Saddam and gave power to Iran-backed political parties and militias. The Axis expanded further after the 2011 Arab Spring, when regional instability created power vacuums that Tehran exploited. Iranian-backed Houthis in Yemen capitalized on the unrest, gaining control over large portions of the country. More recently, Iran deepened its financial and logistical support for Hamas in Gaza.

The strategic logic behind building this network was both offensive and defensive. Offensively, Iran aimed to project influence across the region and counterbalance the presence of rival powers. Defensively, Tehran recognized the asymmetry in conventional military power between itself and Israel and the United States. By relying on partners, Iran sought to build a deterrent force that could absorb pressure and retaliate in the event of a direct attack. These militias were intended not just as strategic buffers, but as integral parts of Iran’s deterrence doctrine.

Yet, since the start of this latest and most serious Iran-Israel and now Iran-U.S. conflict, these groups have been remarkably quiet. Even the Houthis, who had previously launched regular attacks against Israel in 2024, have scaled back their operations so far, following a cease-fire agreement reached with the United States in May. Hezbollah, which was decimated by an Israeli offensive last year, has yet to take meaningful action, and Iraqi militias have remained silent. This raises two fundamental questions: what remains of the Axis of Resistance and what would it take to bring it off the sidelines?

Israeli strikes decapitated Hezbollah, killing its longtime leader Hassan Nasrallah and his key lieutenants as well as destroying launchers, depots, and key artillery batteries. At the same time, the fall of Assad’s regime in December 2024 deprived Tehran of its land bridge to Lebanon and degraded the corridors through which rockets and precision-guided munitions once flowed. Hezbollah leaders know that, in an all-out war, resupply would be uncertain at best. Parallel political headwinds compound the problem. In Lebanon, the new president, Joseph Aoun, has questioned Hezbollah’s right to maintain an autonomous military wing; in Iraq, similar debates surround the Popular Mobilization Forces (PMF) and their semi-autonomous status. Yemen’s Houthis face their own public discontent after repeated U.S.-Israeli strikes on ports, power plants, and airports that have crippled essential services. All three factions, therefore, risk domestic backlash if they are seen as dragging their populations into a wider war simply to further Tehran’s agenda. Yet their long-term survival still depends on Iranian financing and materiel, leaving them torn between self-preservation at home and loyalty to their sponsor should the regime in Tehran appear genuinely imperiled.

Another reason for the current paralysis of Iran’s network lies in the assassinations of senior Islamic Revolutionary Guard Corps (IRGC) generals. Israel’s recent operations have eliminated Esmail Ghaani, the head of the Quds Force; Mohammad Bagheri, the Chief of Staff of Iran’s Armed Forces; and the commander of IRGC intelligence. These losses have significantly undermined Iran’s ability to coordinate and direct its allied militias across the region.

With experienced Quds Force handlers gone, lines of communication with militia commanders have likely slowed down or lost momentum. The Quds Force, which traditionally served as the IRGC’s main instrument for managing Iran’s extraterritorial operations, has been struggling to recover. This has created a severe command vacuum, disrupting coordination and delaying strategic decisions across Iran’s militia network. In the aftermath of Bagheri’s death, the Chief of Staff role has reportedly been assumed by General Abdolrahim Mousavi of the regular army (Artesh), a striking change. Historically, the Artesh has remained institutionally distinct from the IRGC and has had minimal involvement in managing Iran’s overseas operations. Its sudden elevation to fill the leadership gap has likely added friction and confusion, as Artesh officers lack the experience and established networks required to oversee cross-border militia coordination.

The result is a fractured and overstretched command structure. Hezbollah, the PMF, and the Houthis, accustomed to tight IRGC guidance, are now left in a holding pattern, uncertain of how to proceed without clear operational leadership from Tehran.

The third key reason for the militias’ failure to enter the fray so far is that Tehran appears sensitive to explicit American warnings. Iranian decision-makers know that unleashing these groups against U.S. targets in the region might prompt Washington to enter the war even more fully than it has already done, an outcome Iran hopes to avoid while still reminding the U.S. that it possesses this latent leverage. Now that U.S. forces have joined the fight, militia leaders face an excruciating choice: defend their patron and confront both Israel and the United States, or stand down and risk losing Iranian support, and perhaps their own relevance, in the long run.

If these three drivers indeed explain the current restraint, Tehran will eventually have to reassess a “forward defense” doctrine that it has relied on for four decades. Should the Islamic Republic survive this war, its leaders must ask whether the Axis of Resistance still serves as an effective shield or whether future resources should shift toward indigenous missile forces, drones, air defense, and intelligence capabilities that have proven more dependable in the present crisis.

Arman Mahmoudian is a research fellow at the Global and National Security Institute (GNSI), and a lecturer at the University of South Florida (USF). His handle on X, formerly known as Twitter, is @MahmoudianArman