(Bloomberg) -- The escalating conflict between Israel and Iran has raised anew the possibility of all-out war between them. Blaming Israel for the July 31 killing in Tehran of the political chief of the Iran-backed Palestinian group Hamas, Iran has promised to retaliate. Should it come to full-fledged war, one of Iran’s most valuable assets would be the network of allied foreign militias in addition to Hamas that it has supported and nurtured for decades. The militias have already stepped up actions against Israel since the start of its war with Hamas in October.
Iran has been funding and arming militant groups abroad since soon after the 1979 Islamic Revolution as the nation’s new fundamentalist Shiite Muslim leaders sought to spread their mission to the rest of the region. The groups are nurtured by Iran’s Quds Force, a wing of the country’s elite Islamic Revolutionary Guard Corps that emerged from Iran’s 1980-1988 war with Iraq. Though Iran fought Iraq’s better armed, Western-backed forces to a standstill, the economic and human cost was devastating. Iran’s leaders have mostly avoided open warfare since. Though Israel and Iran did exchange direct aerial attacks in April, Iran generally has preferred the deniability and lower casualty rates offered by the use of covert operations and proxy forces belonging to its so-called Axis of Resistance.
Hezbollah
The initial focus of Iran’s militia strategy was in Lebanon, where it backed the Shiite group Hezbollah. Hezbollah was formed in 1982 in reaction to Israel’s occupation of the country’s south and was inspired by Iran’s revolution. Though Israel withdrew from Lebanon in 2000, Hezbollah has continued to attack it, saying Israel still occupies a patch of Lebanese territory. Israel and Hezbollah have fought repeated battles, including a war in 2006. After the Oct. 7 Hamas attack that set off that group’s latest war with Israel, Hezbollah began launching missile, mortar and rocket strikes on northern Israel in solidarity with the Palestinian group. The group vowed to retaliate for Israel’s killing of Hezbollah commander Fuad Shukr in Beirut July 30, which Israel said was in response to an attack it blamed on Hezbollah that killed 12 young people at a football field in the Israeli-controlled Golan Heights.
Like Hamas, Hezbollah is designated by the US as a terrorist organization. The group is thought to have been behind a number of major attacks on US targets in the 1980s. Authorities in Argentina blamed Hezbollah for two bombings in Buenos Aires, one at the Israeli embassy that killed 29 people in 1992, the other at a Jewish community center that killed 85 people two years later. The US and Israel say Iran was behind the bombings.
Houthi Rebels
The Quds Force was designed, Iran’s Supreme Leader Ali Khamenei said in 1990, to “establish popular Hezbollah cells all over the world.” The most recent expression of that policy is Iran’s elevation of Yemen’s Houthi rebels. The Houthis, followers of the Zaidi branch of Shiite Islam, have controlled northwestern Yemen since civil war broke out in 2014. Iranian weapons, training and intelligence have enabled them to significantly improve their military abilities. In solidarity with Hamas, they have launched repeated attacks on ships plying the Red Sea, disrupting global trade, and have fired missiles and drones at Israel. On July 19, a Houthi drone hit a building in central Tel Aviv, killing a man and injuring several others.
Shiite Militias in Iraq and Syria
Iran’s policy of backing militants in other countries expanded dramatically after the US-led invasion of Iraq in 2003, which brought about 150,000 American troops to Iran’s border, as well as a long-sought opportunity to dominate Iraq — once part of the Persian Empire based in what is modern-day Iran — through the country’s newly empowered Shiite majority. The Revolutionary Guards began organizing and arming Shiite militias with roadside bombs and other equipment to attack US forces in Iraq, with the goal of driving them out.
Iran’s backing of Shiite militias in Iraq moved into the open in 2014, when the Iraqi government formally endorsed them as a means to fight the extremists of Islamic State, under the umbrella designation of Popular Mobilization Forces. Their firepower and prominence gave Iran leverage to shape Iraqi governments.
In Syria, Iran intervened to preserve its only state ally, Bashar Al-Assad, against what began in 2011 as a popular rebellion, mainly among his country’s majority Sunni population. Unwilling to commit large numbers of its own troops, Iran enlisted Hezbollah and militias from Iraq, as well as Shiites from Afghanistan and Pakistan to fight in Syria. Though it took Russia’s help, the policy succeeded in saving Assad and securing a land route for Iranian military supplies, from Tehran to Lebanon.
Since the Israel-Hamas war began, US forces in Iraq, Syria and Jordan have come under increased attacks from Iran-backed militias; an umbrella organization calling itself the Islamic Resistance has often taken credit. The attacks dropped off for a time after the US launched major retaliatory strikes in February, including against targets linked to the Revolutionary Guards.
After Oct. 7, Israel stepped up strikes against Iran-backed militias in Syria after they moved close to the Israeli border, and Iran has blamed Israel for a number of deadly strikes on the Revolutionary Guards in Syria. It was such an attack in April, which killed seven Iranian military personnel including a top commander of the Revolutionary Guards, that precipitated Iran’s subsequent missile and drone attack on Israel.
Varying Degrees of Control
The degree of control Iran exercises over militias it supports varies. On one end is Iraq’s Kataib Hezbollah, a constituent of the Islamic Resistance, which is thought to function like an entity under Iran’s direct command. In the middle is an ideological ally such as Hezbollah, which would pursue common goals even if Iran lost interest. At the other end is Hamas, which unlike the other groups is made up of Sunni rather than Shiite Muslims. Hamas is a partner of expediency that will align with Iran only so long as that serves its financial and political interests.
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--With assistance from Marc Champion.
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