Kelly Campa, Johanna Moore, Alexandra Braverman, Katherine Wells, Ria Reddy, Robert Moore, William Doran, and Nicholas Carl

Information Cutoff: 2:00 pm ET

Iran and its Axis of Resistance may target US forces in Syria as part of a retaliatory strike for Israel killing several Axis of Resistance leaders, including Hamas Political Bureau Chairman Ismail Haniyeh. Euphrates Post reported that Iranian-backed Iraqi militias Kataib Hezbollah, Sayyida al Shuhada, and Harakat Ansar Allah al Awfiya deployed fighters to eastern Syria on July 31 “with the aim of targeting the International Coalition bases in Hasakah Governorate. Euphrates Post sources in Homs Governorate reported that unspecified Iranian-backed fighters have moved “heavy equipment” and rocket launchers from militia warehouses in Jabal al Mazar into the desert east of Palmyra. Iranian-backed Iraqi militias conducted over 170 attacks targeting US forces in Iraq and Syria between October 2023 and January 2024 including US positions in Hasakah and Homs Governorates Mashhad Friday prayer leader Ahmad Alam ol Hoda claimed that US support for Israel emboldened Israel to kill Haniyeh in Tehran and declared that “[Iran] demands blood” from the United States.

Iran is very likely taking into consideration US and allied support defending Israel as it considers how to cause greater damage than the April 2024 attack did. Iran and its allies fired around 170 one-way attack drones, 30 cruise missiles, and 120 ballistic missiles at Israel in the April 2024 attack. Iran designed this strike package of over 300 projectiles to inflict serious damage on Israel. The United States and allied forces in the region intercepted a majority of the drones and missiles en route to Israel during Iran’s April 2024 attack. The United States, Israel, and allied countries in the region collectively intercepted approximately 99% of all munitions launched by Iran during its April 2024 attack.

Iranian-backed militia attacks targeting US bases in Syria could pull resources away from engaging and intercepting munitions bound for Israel in some circumstances. If the United States had to focus on defending US ground positions, Iran could calculate that the effectiveness of the integrated regional air defense that defended Israeli territory in April 2024 would be reduced. Tehran might expect that attacks targeting US forces in combination with a large-scale drone and missile attack conducted by the Axis of Resistance could be significantly more effective. Achieving the greatest impact of attacks on US forces to draw resources away from intercepting Iranian strikes against Israel would require a high degree of coordination across the Axis of Resistance and would need to be precisely timed. It is far from clear that Iran and its proxies and partners could coordinate many disparate air and ground operations that finely. US and allied forces can also take many measures to mitigate these risks.

The following indicators would support the hypothesis that Iranian-backed militias are preparing to attack US forces in eastern Syria.

• Iranian-backed militias massing additional forces in or around eastern Syria
• Iranian-backed militias leaving their stations in western Iraq or other parts of Syria
• Iranian or Iranian-backed militia leaders meeting in eastern Syria
• Iranian-backed militias flying ISR drones around US forces in eastern Syria
• Iranian-backed militias in eastern Syria conducting exercises simulating attacks on US forces
• Iranian or Iranian-backed militia leaders in eastern Syria taking heightened security precautions
• Iranian or Iranian-backed sources signaling publicly the possibility of intensified conflict in eastern Syria
• Iranian-backed militias rapidly increasing the dissemination of anti-US disinformation in eastern Syria

CTP-ISW has not independently observed confirmation of any of these indicators, and many of them are unlikely to be observable in the open-source environment.

Key Takeaways:

• Syria: Iranian-backed Iraqi militias have moved fighters and weapons to eastern Syria in order to attack US forces there, according to local Syrian reports. Iran directing a militia attack on US forces at the same time as an Iranian drone and missile attack on Israel could hinder the United States’ ability to defend Israel.

• Iran: Anonymous Western intelligence sources told Sky News Arabia that Iran and Lebanese Hezbollah may attack Israel on the Jewish holiday Tisha B’Av on August 12-13 in retaliation for Israel killing Ismail Haniyeh.

• Israel: US and UK officials have engaged Israel to affirm support and coordinate defensive action in preparation for an Iranian-led attack on Israel.

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ISW–CTP has launched an interactive map of Israeli ground operations to accompany our daily campaign assessments of the Israel–Hamas war. This product complements the daily static maps that ISW-CTP produces with high-fidelity and, where possible, street-level assessments of the war in Israel.

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