(Bloomberg) -- Earlier this month, Kamleh Al-Yaseeni was supposed to accompany a friend to a hospice for the elderly in Damascus where they both volunteered, but she changed her mind to stay home with her disabled son, friends and neighbors said. It was a decision that would cost both their lives.

The Syrian family died in an airstrike on the three-story building they lived in that also took out high-ranking Iranian military leaders responsible for conducting proxy operations in Syria and Lebanon. Israel neither confirmed nor denied the strike, but the attack was cited by Tehran as the reason for last weekend’s missile-and-drone barrage, Iran’s first direct assault on the Jewish state.

With US officials saying that Israel carried out retaliatory strikes on Iran early Friday, the world is waiting to see whether more is to come or if the spiral of direct reciprocal actions stops here. What is clear is that a central component of Tehran’s arsenal yet to be fully deployed is its proxy forces in Syria, Lebanon, Iraq and Yemen, ready to take on a more prominent role if called upon.  

What Tehran calls its “axis of resistance” has been a central focus of Israel’s military, which has made great efforts to hunt them down — as seen in Damascus and elsewhere. Yet analysts agree their capabilities persist and Iran’s proxy forces could still extract a high cost, ratcheting up the conflict at an increasingly parlous time for the broader Middle East.

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“The greater the threat the more the axis is likely to respond forcefully and aggressively and in a coordinated manner,” said Dina Esfandiary, senior adviser on Middle East and North Africa at the International Crisis Group in London. 

After Friday’s strike, “Tehran will have to rely on its proxies as much as possible” in order to keep the situation “manageable,” she said. “But miscalculation is possible and unpredictable in that scenario.” 

Regardless of how any further direct confrontation between Iran and Israel plays out, Tehran is likely to lean more on its proxies to try to keep the conflict away from its territory, while Israel will surely continue to go after the threats at its borders. Above all that means Hezbollah, the Lebanese militia and political movement that is Tehran’s most important regional proxy force.

Early on Friday, Syria’s Defense Ministry said that Israeli missiles struck its aerial defenses in the south, causing only material damage. There was no comment from Israel, but it is no secret that operatives from Iran and Hezbollah are embedded in Syrian army units there, making them frequent targets for Israel. 

The April 1 strike on the Damascus building was certainly a blow to both Iran and Hezbollah and a trigger for what many still fear: all-out war between Iran and Israel.

Al-Yaseeni, the widow of a former Syrian diplomat in her 70s, was with her son Naji on the first floor of the building just off Mazzeh Highway, one of the Syrian capital’s main thoroughfares. In the apartment directly above, Iranian military leaders responsible for the Islamic Revolutionary Guard Corps’ elite Quds Force in Syria and neighboring Lebanon were holding an urgent meeting, according to people briefed about events on the ground.

The Iranian embassy had been set to move to a new apartment compound further down the same road where two siblings of Syrian President Bashar Al-Assad own properties, the people said.

In the meantime, the embassy had been renting apartments on the second and third floors as residences for the ambassador and the consul. General Mohammad-Reza Zahedi, his deputy General Mohammad-Hadi Haji Rahimi and the five other Iranian officers killed felt it was the safest place in Damascus since a previous Israeli strike took out a senior Iranian officer in Syria in December, according to the people. 

Drones, Missiles

It was Iran’s greatest loss since the US assassinated Quds Force commander Qassem Soleimani in Iraq four years ago, and a huge setback for Hezbollah. In an April 8 televised eulogy that lasted nearly an hour, Hezbollah chief Hassan Nasrallah hailed Zahedi, and said he was “working night and day to serve this resistance” and advance its capabilities. 

After publicly warning that a response was coming, Iran retaliated for Zahedi’s death by firing nearly 300 drones and missiles at Israel, almost all of which were intercepted. 

The question now is how far Tehran will go in the confrontation and what role its proxy forces can play. Starting with Hezbollah in the 1980s, Iran has built up its network of forces and alliances in the Middle East for an all-out battle scenario with Israel. Iran-backed Palestinian militant group Hamas’ Oct. 7 attack on Israel and Israel’s subsequent invasion of Gaza are providing the pretext for both sides to look over the precipice. 

The proxies have a “coordinated command mechanism” with Iran and could be activated on a much larger scale if “there’s stronger political willingness on the Iranian side to militarily engage with Israel,” said Abdolrasool Divsallar, senior scholar at the Washington-based Middle East Institute.

While missile and drone launches by Iran-backed Houthi militants against ships in the Red Sea have grabbed headlines and remain a serious threat, most of Israel’s attention is on Hezbollah — designated a terrorist group by the US and others — which is believed to possess the most formidable arsenal of missiles among all groups and is present at Israel’s borders in both Lebanon and Syria. 

Zahedi’s death and Israel’s killing of some 300 Hezbollah members and the almost nonstop targeting of its infrastructure and supply lines in both Lebanon and Syria since Oct. 7 have shown the group’s vulnerabilities, said Lina Khatib, associate fellow at Chatham House, a London-based think tank. 

‘Thousand Cuts’

“Israel does not need a full-on attack to achieve its goal of crippling Hezbollah; Israel is pursuing this goal through a strategy of a thousand cuts,” she said. Even so, for now Hezbollah remains far from being “significantly weakened,” she added. 

It’s an assessment shared by a Western diplomat who said that Hezbollah is still relatively active and seems untouched. Reported withdrawals of Iranian personnel in Syria could also be a sign of the Islamic Republic wanting to engage more covertly in the area to protect its supply lines to Lebanon and Hezbollah, the diplomat said, asking not to be named because of the matter’s sensitivity.

Four days before the strike that killed Zahedi, Israel carried out what was probably its most significant — and lethal — attack in Syria since it began targeting Iran and Hezbollah’s presence in the country in 2012. It destroyed a plant near the northern city of Aleppo where warheads for missiles destined mainly for Hezbollah were being assembled, plus a depot at the city’s airport used to store weapons flown in from Iran, according to people briefed on the attack. It also killed six Hezbollah operatives in their homes in Aleppo; at least 34 others were killed.

“A lot of facilities have been hit but Hezbollah is still extremely capable,” said Matthew Levitt, a leading expert on the group who previously directed the counterterrorism program at the Washington Institute for Near East Policy.

Following Oct. 7, Iran has demonstrated for the first time how its proxies can operate in a synchronized and calibrated manner, according to congressional testimony last month by US Central Command chief General Michael E. Kurilla. Iran has worked for decades to “strategically encircle” US allies in the region and is exploiting what it sees as “a once in a generation opportunity to reshape the Middle East” to its advantage, he said.

‘Dangerous Game’

In Iraq, one of Iran’s main proxy groups, Kataib Hezbollah, which had several of its members killed by the US in February in retaliation for a lethal attack on American troops in Jordan, has been threatening to engage in a more regional role in support of Iran and its allies. Earlier this month, one of its commanders vowed to flood neighboring Jordan with weapons for a march on Israel.

In Yemen, the Houthis’ role in the event of a sustained confrontation between Iran and Israel that could potentially draw in the US and its allies may actually exceed that of “all of Iran’s other arms in the region,” estimates Adnan Al-Gabarni, a Yemen-based researcher on the group. 

The Houthis could completely shut down the Arabian and Red seas to all navigation, attack US military bases and assets in the region and launch drones and missiles at Israel along with other proxies in order to overwhelm missile defense systems there, he said.

For all Israel’s attacks and assassinations in Lebanon and Syria, US-UK strikes on the Houthis, and Washington’s targeting of Iran’s main proxies in Iraq, Iran’s axis of resistance retains its “actual capabilities,” according to the Middle East Institute’s Divsallar.

How those proxies are mobilized if the need arises will be carefully calibrated by Tehran according to what Israel might hit inside Iran and the damage caused, Hezbollah expert Levitt said before Friday’s reported strikes. Anything is possible, including attacks on Israeli and Western targets outside the Middle East. 

“It’s a dangerous game,” said Levitt. “There are lots of different ways this can go sideways.” 

--With assistance from Mohammed Hatem.

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