Iran File: Iranian Proxies Increase Attacks on US Forces to Catalyze a US Withdrawal from Iraq

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Key takeaway: Iran’s Iraqi proxies have likely become more willing to kill Americans and may soon do so to catalyze the withdrawal of US forces from Iraq and Syria. These proxies are advancing an Iran-directed campaign that has increased in frequency, accuracy, and lethality since January 2021. This campaign is expanding to include not just Iraq but also Iraqi Kurdistan and Syria. Proxies have also begun using more lethal munitions and drones that can bypass US defenses. Attacks will continue until US forces withdraw from Iraq and Syria or reestablish deterrence with both Iran and its proxy network.

The Iran-directed escalation campaign to expel US forces from Iraq and Syria has changed in five ways since the Biden administration took office in January 2021:

  1. Proxies are increasing the frequency of their attacks against US forces in Iraq. The militias have conducted 20 rocket attacks and 11 *drone *attacks on US personnel and facilities in Iraq and Syria since President Biden took office in January 2021. Six of those attacks occurred in the first week of July alone. That is a dramatic increase in tempo compared to the five proxy rocket attacks conducted in the final three months of the Trump administration. Iran and its proxies remain demonstrably undeterred.
  2. Proxies are increasingly attacking US intelligence and military assets in the once-protected Kurdistan Region of Iraq (KRI). Iran’s proxies conducted their first known attack on US forces in the KRI under in September 2020, firing six rockets at Erbil International Airport from beyond the KRI borders. The small-caliber rockets caused no casualties. Proxies have attacked US facilities inside the KRI five times since then, including a 14-rocket barrage in February 2021. Drone attacks targeted an alleged CIA hangar at Erbil International Airport in April, a presumed US Joint Special Operations Command headquarters at Harir airbase near the Iranian border in May, a *civilian house in Erbil Province in June, and Erbil International Airport again in July. The June attack triggered US retaliatory airstrikes along the Iraq-Syria border.
  3. Proxies are increasing the geographic scope of their escalation to include US basing in Syria. The US retaliatory strikes struck minor Iranian proxy facilities in Iraq’s Anbar Province and Syria’s Deir ez-Zor Province on June 28. Proxies fired 34 122 mm rockets at US forces stationed at a counter-ISIS forward operating base in Deir ez-Zor known as Green Village hours after the US strikes. US air defenses at Green Village prevented injury—never a guarantee with such large salvos of high-caliber munitions. Proxies conducted another drone attack against the same US base on July 7, likely demonstrating their intention to continue targeting forces in Syria as well as Iraq.
  4. Proxies appear increasingly willing to inflict US casualties. The June 28 attack on Green Village in Syria is one of the largest attacks against the United States in the Middle East since US forces withdrew from Iraq in 2011—second only to Iran’s ballistic missile attack on Ain al-Assad airbase after the killing of Qassem Soleimani in January 2020. The scale of the Green Village attack indicates that Iran and its militias intended to inflict casualties. The 122 mm rockets used are larger and more lethal than the usual 107 mm Katyushas that proxies use in harassing attacks throughout the region. Other attacks in 2021 have also demonstrated a readiness to inflict casualties, including the February 15 attack on Erbil International Airport that killed one and injured 14 and the July 7 rocket barrage on Ain al-Assad that injured two.
  5. Proxies are demonstrating increasingly advanced drone capabilities to bypass US defenses. Iran-backed Iraqi militants conducted their first drone attack targeting a presumed CIA hangar in Erbil on April 14, 2021. They have since conducted nine additional drone attacks in Iraq and Syria. The drones used are coded with their targets’ GPS coordinates, often evade the US air defense systems that regularly intercept rocket attacks, and have struck multiple sensitive US assets.

Iran has likely calculated that causing US casualties will motivate a US withdrawal from Iraq and Syria. Iranian leadership holds that the United States is extremely casualty-averse. Tehran and its proxies likely believe that even a small number of US casualties in Iraq and Syria could convince the Biden administration to withdraw forces from those theaters—a key Iranian strategic objective. Iran and its proxies are likely emboldened by the US withdrawal from Afghanistan and believe that a similar bleeding of the US political will to remain will achieve the same outcome in Iraq. The head of the Iran-backed militia Asa’ib Ahl al-Haq, Qais al-Khazali, *announced in April that “dialogue and logic does not work … the Afghan method is the only way to expel [US forces from Iraq].”

Iran will continue its campaign to expel US forces from Iraq and Syria regardless of the outcome of US-Iran negotiations to restore the Joint Comprehensive Plan of Action (JCPOA). Iran’s leadership has seemingly assessed that the Biden team is prioritizing the JCPOA above all else. That calculation has also emboldened them. Tehran is likely concerned that a future American president will pursue another “maximum pressure” policy similar to that of the Trump administration. The regime will therefore try to prepare itself economically and militarily to better resist coercion upon the potential return of maximum pressure during or after the Biden administration. Proxy attacks will likely continue so long as Iranian leaders see little risk and the potential for a huge reward (the withdrawal of US forces from Iraq and Syria).

Forecast: Iran’s proxies in Iraq and Syria will likely continue to escalate against US forces and facilities until the United States withdraws its forces or reestablishes deterrence. Escalations will likely include simultaneous rocket and drone attacks to better evade US defenses in Iraq and Syria, the use of larger, more lethal munitions like 122 mm rockets, and the continued targeting of alleged US intelligence assets in Iraqi Kurdistan. Proxies will increasingly aim to inflict US casualties to create a politically untenable situation for the Biden administration, thereby catalyzing a US withdrawal.

This analysis is co-published by the Institute for the Study of War (ISW) and the Critical Threats Project at the American Enterprise Institute.