Axis of Resistance

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Last updated on December 3, 2025
 

Introduction

The Axis of Resistance is a loosely aligned network of armed groups and state actors led and supported by Iran to project its influence and military strength across the Middle East. Tehran has varying levels of sway over these groups, and while some, like Hizballah in Lebanon, coordinate closely with their Iranian patrons, others are allies of convenience that limit cooperation to areas where their interests overlap, such as Yemen’s Houthis. Although Axis of Resistance members mostly operate independently of one another, they share certain key objectives, such as the expulsion of American presence and influence from the Middle East, the destruction of the State of Israel, and support for the Palestinian resistance movement. Iran’s capabilities have been degraded by recent developments in the region, but both the regime and its proxies are expected to continue to pose significant threats to the United States and its allies.

The Axis of Resistance and Iran’s National Security Strategy

The Iranian regime provides support to its proxies and allies through the Quds Force branch of the Islamic Revolutionary Guard Corps (IRGC), a military-political organization with enormous influence in Tehran. Iran is far from the first country to use proxies to advance its interests, but its decades-long commitment to this approach is atypical. From Iran’s perspective, its national security objectives require a “forward defense” strategy that uses armed proxy groups abroad to prevent war from reaching Iranian soil while exploiting plausible deniability of their actions to avoid being dragged into direct conflict. In recent years, Iran encouraged its allies to adopt a “unity of fronts” strategy which theorized the network could exert more influence over Israel and the US by coordinating their actions. Scarred by the experience of Iran’s eight-year-long war (1980-88) with Saddam Hussein’s Iraq, Tehran sees forward defense as a cost-effective means of deterrence against attempts to attack or destabilize its regime. In effect, from the vantage point of Iran’s neighbors and the West, this strategy has been used to advance Iran's influence across the region, including by fighting and overturning governments not allied to it, exporting the Iranian revolution, and attacking Israeli and American interests.

The Iran-Iraq war of the 1980s was the Islamic Republic’s critical testing ground with armed proxies. A budding Quds Force co-opted anti-Saddam Iraqi Kurds — cultivated as allies against Baghdad since the days of the shah — and Iraqi Shi’as, leveraging longstanding grievances against Hussein’s regime. Following the war and throughout the 1990s, Iran’s foreign policy was flexible when necessary rather than subordinated to ideological or religious principles. Iran supported Christian Armenia against Azerbaijan, a fellow Shi’a country, and collaborated with a range of Sunni groups, including the Northern Alliance, a multi-ethnic coalition of Afghan militias fighting the Taliban. Since the Taliban’s return to power in 2021, Tehran and Kabul have taken tentative steps to improve relations, although Iran has not yet extended diplomatic recognition to the anti-Shi’a extremist group’s government.

For decades, Tehran viewed support for foreign armed groups as a low-risk, inexpensive way to fight or deter its enemies — an important consideration given that Iran is one of the most heavily sanctioned countries on the planet and its economy is under severe pressure. Iran’s regular military is also deficient in several key areas, with outdated military hardware and a reliance on missiles and drones for deterrence. Proxies provide a workaround to Iran’s lack of state allies and its conventional military weakness, albeit at the heavy price of Iranian diplomatic and economic isolation. The regime also lacks domestic support for its agenda and must expend considerable resources policing the opposition and suppressing widespread unrest at home.

Key Members

The Axis of Resistance includes a range of political and militant groups spanning the Middle East. Although the name was adopted in response to President George W. Bush’s 2001 speech about the “Axis of Evil,” the evolution of a network of resistance organizations began much earlier. The core members extend across the region: Lebanon’s Hizballah, Iraq’s Popular Mobilization Forces (PMF), the Houthi militia in Yemen, the Afghan Fatemiyoun militia, the Pakistani Zainabiyoun militia, and Palestinian militant groups Hamas and Palestinian Islamic Jihad (PIJ). Bashar al-Assad’s Ba’athist regime in Syria, before its collapse in December 2024, was aligned with the axis, although it differed from the other groups due to its secular nature and refusal to prioritize confrontation with Israel. The axis was expanded under the direction of Major General Qasem Soleimani, who commanded the Quds Force for two decades before his assassination by the United States in 2020. Soleimani significantly enlarged the Axis of Resistance by exploiting the permissive environment in countries with weak central governments and discontented local groups to influence, and in some cases commandeer, the decision-making process in support of Iran’s foreign policy agenda.

Hizballah and the Rise of the Axis

Shortly after Israel’s 1982 invasion of civil war-torn Lebanon, Quds Force operatives deployed to the country to export the Islamic Revolution and build a Shi’a Islamist organization capable of fighting Israel. The result was Hizballah, which eventually monopolized resistance to the Israeli presence, attacking both the Israeli military and the multinational force assisting the Lebanese military, the United Nations Interim Force in Lebanon (UNIFIL). In 2000, the Israel Defense Forces (IDF) unilaterally withdrew from their occupation of southern Lebanon, enabling Hizballah to laud itself as the only Arab force to competently engage the Israelis in battle. In 2006, after a Hizballah cross-border raid, Israel invaded again; but the operation proved indecisive, and the IDF withdrew after a month, allowing the Tehran-backed militant group to claim victory again. Hizballah’s successful resistance to Israel energized its members and propelled the wider Axis of Resistance to early prominence. The Lebanese militant group also served as a blueprint for Iran to build a security infrastructure that enabled it to project power, disrupt its adversaries, and shape the short-lived “unity of fronts.”  

The IRGC was able to create a formidable foreign organization powerful enough in its own right to propagate the Iranian regime’s ideology and exert pressure on Israel. Yet some of the success owed to Hizballah’s particular nature and the specific environment from which it emerged. Hizballah rapidly grew into an influential political force within Lebanon’s Shi’a community by appealing to Islamism, sectarian anxieties amidst civil war, and a desire to resist the Israeli invasion as well as Western influence. Transforming through several stages, from a terrorist group targeting Israel to a conventional militia waging war against other actors in Lebanon’s civil war to a national liberation movement against Israeli occupation, it effectively built a “state within a state,” providing social services in bastions of support and possessing an armed strength often thought to surpass that of the regular Lebanese military. Hizballah pledged allegiance to Iran’s supreme leader and operates in lockstep strategically and ideologically with the Islamic Republic.

"Before his assassination by the US in 2020, Quds Force commander Major General Qasem Soleimani significantly enlarged the Axis of Resistance by exploiting the permissive environment in countries with weak central governments." 

After the US invasion of neighboring Iraq in 2003, the Iranian regime feared it would be next. For decades, Tehran had been cultivating Iraqi Shi’a Islamist groups like the Badr Organization, composed of Iraqi exiles based in Iran and loyal to Iran’s supreme leader. But the Iraq war and toppling of Saddam Hussein also spurred the emergence of a number of new Iran-affiliated Shi’a militias in the country, including Saraya al-Salam (Mahdi Army), Kata’ib Hizballah, and Asaib Ahl al-Haq. Qassem Soleimani fostered an assortment of such “Special Groups,” as they were designated by the United States; these paramilitaries killed hundreds of American troops and allowed Iran to influence Iraqi politics up until the start of the US surge strategy in 2007.

Under Soleimani’s patronage, the pro-Iranian militias in Iraq and Syria developed into a “transnational Shi’a army” and an instrument of Iran’s influence. Although Iran and the US temporarily shared an informal convergence of interests in fighting ISIS, particularly between 2014 and 2017, once the Islamic State was finally routed in Baghouz, Syria, in 2019, the Shi’a militias redirected their attention to the US presence in Iraq. On December 27, 2019, a US airbase in northern Iraq was targeted by missiles reportedly fired by Kata’ib Hizballah. A US contractor was killed and four service members were injured. The US responded on December 29 with strikes on the group's positions that killed 25 fighters. On December 31, members of Kata’ib Hizballah and the PMF and their supporters stormed the US Embassy in Baghdad. On January 3, 2020, a US drone strike killed Soleimani outside the Baghdad airport as he returned from a visit to Syria. In statements about Soleimani’s death, US government officials said he represented an imminent threat to American lives and interests.

Syria and the Assad Regime

Baathist Syria was a particularly notable member of the Tehran-led Axis of Resistance as the network’s only recognized state — other than Iran itself — and the sole Arab-majority country allied with the Iranian regime. Its strategic importance to Tehran extended far beyond any battlefield contributions Damascus could or might occasionally provide. Close Syrian-Iranian relations date back to 1979. During the Iran-Iraq war, Syria provided political, economic, and limited military backing to the Iranian regime in an effort to contain Iraq. And in ensuing decades, Syrian territory played a critical role as a physical corridor linking Iran to its proxies in the coastal Levant: namely, Hizballah and several Palestinian militant groups. But that relationship changed further with the onset of the Syrian civil war.

As the Americans were completing their first withdrawal from Iraq in 2011, the Arab Spring wave of popular uprisings began to spread across the region. When pro-democracy protests in Syria turned into an armed rebellion after a lethal crackdown by the Assad regime, the embattled Syrian leader turned to Iran for support. To prop up Assad, the Quds Force exploited religious and ideological appeals to form militias composed of foreign Shi’a fighters, such as the Afghan Fatemiyoun and the Pakistani Zainabiyoun brigades. The IRGC also deployed thousands of its own soldiers, as well as its Iraqi proxies and Lebanese Hizballah, creating a transnational Shi’a army operating at Iran’s direction, generating unease and fear among Iran’s regional adversaries. Iranian assistance to Assad — manpower, training, and billions of dollars in credit — strengthened the regime’s position against its opposition. It also came at a considerable cost to Hizballah's reputation, turning it from the group that fought off the Israelis to the one that crushed the aspirations of the Syrian people in the eyes of many in the Middle East.

"Prior to Assad's downfall, Syria played a critical role as a physical corridor linking Iran to its proxies in the coastal Levant."

In return for more than a decade of material assistance and billions spent intervening in Syria’s civil war, Iran’s embassy in Damascus was looted and its “Marshall Plan” for post-war reconstruction was shredded when Assad’s regime was toppled by Sunni Islamist rebels in December 2024. Iranian businesses, religious sites, investment projects, and military installations were abandoned, and the former Syrian regime reportedly owed Iran more than $30 billion. Turkey and Israel moved in to fill the political, military, and geographical spaces vacated by Iran’s retreat. There are reports of indirect contact between the Iranians and the new Syrian government, but President Ahmad al-Sharaa seems to have calculated that Syrian interests would be best served by pursuing sanctions relief, assistance, and support from Western and Arab allies. Although there is some speculation that Iran’s interests could align with Turkey against Israeli encroachment on Syrian territory, or (informally) with Israel in supporting minority groups against Turkish and Syrian domination, the extent and nature of Iran’s future influence in Syria remains to be seen.  

Yemen and the Houthis

The Arab Spring also gave Iran an opportunity to deepen its cooperation with the Houthi movement, or Ansar Allah, a group composed of members of Yemen’s Zaydi Shi’a minority. Houthi militants had been launching sequential military offensives against Yemen’s government since 2004. Longtime enemies of Iranian rival Saudi Arabia, they had also fought against the Gulf monarchy since 2009. In 2011, as Yemen’s Arab Spring uprising and widespread defections from the Yemeni army caused general instability, the Houthis expanded their control over the country’s north. The Houthi insurgency escalated into a civil war in 2014 after the group seized Yemen’s capital, Sana’a. Iran, which had faced persistent accusations of backing the insurgents, used the opportunity to expand its support to the Houthis, covertly providing greater arms and training to the militant group. The relationship between the Houthis and Tehran is more complex than that of many of the other Axis members, and the movement remains broadly independent. Many scholars point out that Iran has little control over the group’s decision making, while others go a step further and refer to the Houthi movement as the Iranian regime’s willing partner, rather than a proxy as such. In transactional terms, Iran benefits from this relationship by providing drones and missiles to the Houthis in exchange for attacks that disrupt international shipping in the Red Sea, keep Saudi Arabia preoccupied, and occasionally target Israel.

Iraq and the Popular Mobilization Forces

When the Islamic State (ISIS) attacked Syria and Iraq in 2014, Iran used the opportunity to capitalize on the jihadist threat as well as on the US approach to consolidate its proxies there. To fight ISIS, Iraqi militias, predominantly Shi’a groups, coalesced under the Hashd al-Shaabi, or PMF, an umbrella group that nominally answers to the Iraqi prime minister but many of whose components operate at Tehran’s direction. Although the PMF ultimately played only a minor role in the war against ISIS, they were important early on in the conflict in reassuring Iraqis and blocking ISIS from taking over Baghdad. Nevertheless, they could not dislodge ISIS on their own, generally complicated the successful American-backed operations of the Iraqi security forces (ISF) to defeat ISIS, and routinely took over territory liberated by the ISF to terrify and subjugate the predominantly Sunni Arabs living in those areas. After the ISIS threat was reduced, thousands of Iran-affiliated Iraqi militia fighters went to Syria in 2016 to battle rebels and bolster the Assad regime.

Iran’s continued sway over the PMF is an important tool for bending Baghdad to Tehran’s will, undermining Iraqi ties with the West, and advancing Iranian interests in the region. In October 2023, the Islamic Resistance in Iraq (IRI), a coalition of pro-Iran militias within the PMF, renewed targeted attacks on US bases in the Middle East with drone and missile strikes. Iran, wary of escalation, moved to rein in its Iraqi partners after three American soldiers were killed in a drone strike on a base in Jordan in January 2024. That the militias heeded this instruction is demonstrative of Iran’s control over their Iraqi proxies. Iran’s penetration of the Iraqi state is not limited to armed groups: the regular Iraqi government is dominated by Iran’s supporters, including the head of its top court and elements of the ruling bloc known as the Shi’a Coordination Framework. In July 2025, the Iraqi parliament considered draft legislation to upgrade the PMF from a temporary commission to a permanent arm of the state, a move that would solidify Iran’s influence over the Iraqi government.

Hamas and the Palestinian Islamic Jihad

Iran’s support for Palestinian resistance movements is a key component of the Islamic Republic’s ideology, and despite sectarian differences, Shi’a Iran has worked to strengthen Sunni Palestinian armed groups, especially Hamas and PIJ, to encourage Palestinian militancy. Iran and Hizballah have trained and assisted both groups since Israel expelled hundreds of their members to Lebanon in the late 1980s and early 1990s. After Hamas, joined by PIJ and other militant groups, launched the October 7, 2023, attack on Israel, Tehran denied direct involvement in the operation, a claim that US intelligence supported. However, hundreds of militants trained in Iran in the weeks leading up to October 7, and Iran pointedly did not break off its support for armed Palestinian groups before or after the attack.

In 2024, Israel and Iran exchanged rounds of attacks — Israel targeted the Iranian embassy in Damascus on April 1, Iran launched large missile and drone attacks on Israel on April 13 and October 1, both of which were largely deflected, and Israel retaliated with a series of attacks on Iranian military installations and oil infrastructure on April 18 and October 25. Israel also killed several high-level Hamas and Hizballah leaders, including the assassination of Hamas leader Ismail Haniyeh while he was in Tehran in July, Hizballah secretary-general Hassan Nasrallah in September, and Hamas political head Yahya Sinwar on October 17, and carried out a two-day operation in which thousands of Hizballah members were killed or injured by exploding pagers and beepers in September. In response to the attacks on Iran and the war in Gaza, Hizballah launched hundreds of unguided missiles into northern Israel in the fall of 2024, resulting in at least 100 deaths and precipitating Israeli reprisals that killed more than 4,000 people in Lebanon. A cease-fire brokered at the end of November included provisions for the disarmament of Hizballah.

Iranian Support for Axis Members

Iran has provided extensive military, financial, and logistical support to Axis of Resistance members through the Quds Force. Tracking this aid is complicated, however, given Iran’s efforts to maintain plausible deniability and avoid publicizing assistance to militant groups. Many of these organizations have also developed their own sources of revenue, illicit or otherwise, to underwrite their activities. According to the US government, Iran provided its proxies in Iraq, Syria, and Yemen with more than $16 billion between 2012 and 2020.

Estimates of Iran’s monetary support to Hizballah vary, but the State Department put annual Iranian funding at $700 million in 2020. In June 2016, Hassan Nasrallah, the late secretary-general of Hizballah, confirmed Iran’s support to the group for the first time: “We are open about the fact that Hizballah’s budget, its income, its expenses, everything it eats and drinks, its weapons and rockets, are from the Islamic Republic of Iran.” That said, significant portions of the group’s budget also come from other revenue streams, such as drug trafficking, commercial enterprises, and donations from supporters.

Hamas, as an independent organization, is primarily financed by non-Iranian sources, including redirected funds from front charities, taxation of areas under its control, and aid provided to Gaza by Qatar. Nevertheless, Iran has provided up to $100 million of weapons, training, and money annually to Hamas and other Palestinian militant factions, empowering these groups to greatly expand their military capabilities. This relationship, built on fighting their mutual enemy Israel, has occasionally frayed. Iran briefly curtailed support to Hamas when the group backed the opposition against Assad during the Syrian civil war, demonstrating the limits of Iran’s influence over the organization. Relations between Iran and Hamas were restored in 2017, when Yahya Sinwar assumed leadership of the group. PIJ did not break with Iran over Syria but saw its financial backing from Tehran slashed in 2015 after refusing to denounce the Saudi-led intervention in the Yemeni civil war. Iranian financial assistance for PIJ was fully reinstated in mid-2016, after meetings between PIJ leaders and Iranian officials.

"Iran's continued influence over the PMF is an important tool for bending Baghdad to Tehran's will and undermining Iraqi ties with the West." 

Iran has provided aligned militia groups in Iraq with funds and training as well as substantial military and logistical support, including supplies of drones, rockets, and small arms. Several militias have also developed, with Iranian assistance, independent arms manufacturing capabilities, especially drones. These groups have obtained seats in parliament and engaged in other acts of state capture, thereby benefitting from new sources of revenue and providing Iran with increased influence over the Iraqi government. As a nominal branch of the ISF, the PMF is partially financed from the Iraqi budget, which dispenses $3.4 billion annually in funding for PMF groups. The militias also profit from billions of dollars of diverted customs revenues, exploitative lending, and illegal taxation.

Iran has supplied the Houthis with drones, ballistic and cruise missiles, and training, enabling the group to threaten maritime trade and Iranian adversaries. The total monetary value of this assistance has been estimated at $100 million-$300 million annually out of roughly $1.8 billion in annual revenue from all sources. The Houthis also generate revenue by extorting commercial shipping, levying fees on imports, smuggling illicit drugs and oil, and taxing areas under their jurisdiction.

The Future of the Axis

While the Axis of Resistance has proved resilient to external pressure, the coalition has suffered significant blows since Hamas’ attack on Israel on October 7, 2023. Hamas has been severely weakened as a result of the Gaza war, losing tens of thousands of soldiers and much of its pre-war leadership. Its ability to exert control over Gazans has also diminished, with limited anti-Hamas protests breaking out in March 2025. Hizballah suffered similarly devastating blows in the fall of 2024, with its senior leadership wiped out and much of its military capability lost. The group still retains some military capacity, and along with its allies holds 62 out of 128 seats in the Lebanese parliament, although its political influence is greatly diminished, and it is under domestic and international pressure to lay down its arms.

Hizballah reportedly began redeploying troops from Syria to the conflict in Lebanon in September 2024, resulting in reduced readiness that then forced the group to order additional withdrawals rather than assist Assad as his regime collapsed in December, which further disrupted Iran’s foothold in the region. Assad’s fall from power cut off Iranian supply routes for weapons and money transfers to Hizballah, and the Lebanese and Syrian authorities have cracked down on cross-border smuggling, impeding the group’s reconstitution. In August 2025, the Lebanese government proposed a timeline to bring all weapons under state control by the end of the year, a decision applauded by Washington but rejected by Hizballah and met with protests from its supporters.

Following Israeli strikes on Iranian nuclear facilities in June 2025, a weakened Axis of Resistance failed to deter Israeli or American military action or assist Iran’s strikes on Israel. Hizballah, once on the front line of Iran’s forward defense, watched from the sidelines, unable or unwilling to intervene militarily. The pro-Iran Iraqi militias were similarly restrained, having been warned against attacking the United States or Israel by the Iraqi government.

The continued sidelining of Iran’s Axis of Resistance is not guaranteed. Hizballah and Hamas are weakened, but neither organization has been shattered. Although Hamas retains a presence in Gaza and had reportedly recruited 15,000 new fighters as of January 2025, its popularity has decreased since October 7. According to polling in May 2025, approval of Palestinians in the West Bank and Gaza for the Hamas attack on Israel dropped from 71% to 50%; when considered alone, Gazans’ support for that event stood at 38%. Encouraged by Tehran, Hizballah has so far rejected calls to peacefully disarm, and a significant majority of Palestinians believe disarmament will not lead to Israeli withdrawal or a permanent end to the war. The Houthis appear to be undaunted by US and Israeli airstrikes and have continued to attack Israel and ships in the Red Sea, causing casualties and disrupting international trade. The PMF, which did not take significant actions to support Iran in its conflict with Israel and the US, is divided between protecting its lucrative commercial interests and avoiding sanctions on the one hand and becoming more closely aligned with Iran on the other. The future of the Axis of Resistance will depend on efforts across the region, from Iraq to Lebanon to Yemen, to reassert state control over the use of force and retake power from armed groups. It will also be shaped by the actions of external forces — whether that is the United States, Israel, or the Iranian people themselves.

This backgrounder was researched and written by MEI summer 2025 intern Noah Rudin, with input from Senior Fellow Alex Vatanka and Senior Fellow Fadi Nicholas Nassar.

Top photo by Mohammadali Najib/Middle East Images/AFP via Getty Images

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