October 24, 2023 | Flash Brief

Iranian-Backed Militias in Iraq and Syria Continue Attacks on U.S. Troops

October 24, 2023 | Flash Brief

Iranian-Backed Militias in Iraq and Syria Continue Attacks on U.S. Troops

Latest Developments

An Iran-backed Shiite militia attacked U.S. forces at a base in southeastern Syria on October 23 as similar attacks across Iraq and Syria have increased in the past two weeks. The Islamic Resistance in Iraq — a terrorist group armed and funded by Iran — claimed that its members attacked the al-Tanf military base using two drones. Pentagon spokesman Brig. Gen. Pat Ryder confirmed that U.S. forces thwarted two suicide drones at al-Tanf and that no American personnel were injured.

Ryder added that the United States has seen increased rocket and drone attacks against coalition bases in Iraq and Syria. On October 22, Defense Secretary Lloyd Austin expressed concern about a broader escalation in attacks on American forces in the region in the days ahead. On October 23, National Security Council spokesman John Kirby said, “We know that Iran is closely monitoring these events, and in some cases, actively facilitating these attacks and spurring on others who may want to exploit the conflict for their own good, or for that of Iran.” 

Expert Analysis

“There have been numerous Iran-backed attacks against our troops this week with no response from U.S. forces. The United States has responded in only a handful of the nearly 100 times its forces have come under fire in Iraq or Syria since the start of the Biden administration. The United States should respond to each attack in a similar manner to when U.S. forces neutralized 500 pro-Syrian government forces and Wagner group mercenaries at the Conoco gas fields in 2018, killing more than half of the attackers within a few hours.” Mark Dubowitz, FDD CEO

“Tehran has brushed aside the Biden administration’s warnings and is testing the United States. Washington should ensure our troops have both the means and the permission to defend themselves and make terrorists regret that they attacked U.S. forces. If not, we should not be surprised if Tehran escalates its aggression.” Bradley Bowman, Senior Director of FDD’s Center on Military and Political Power

“Just as Iran, as a supplier and trainer of Hamas, was responsible for the attack on October 7, it is also responsible for the actions of its proxies in Syria, Iraq, and Lebanon. The Department of Defense needs to both surge defensive systems to protect U.S. forces and actually hold Iran accountable for its actions. Rhetoric alone will only encourage further bad behavior.” Mark Montgomery, FDD Senior Fellow and Senior Director of FDD’s Center on Cyber and Technology Innovation

Attacks on U.S. Forces Increased Since Gaza War

The latest attack comes less than a week after Iran-backed militias attacked al-Tanf on October 19, causing minor injuries. On October 22, militias attacked al-Asad air base in western Iraq with rockets after two drones attacked the same base on October 17. On October 18, the Islamic Resistance took responsibility for a drone attack on al-Harir airbase in northern Iraq’s semi-autonomous Kurdish province of Erbil. Shiite militias also targeted the Conoco gas field in the Syrian province of Deir ez-Zor, where a small contingent of U.S. special forces is based.

Approximately 900 U.S. soldiers remain in Syria and approximately 2,500 in Iraq to support efforts to defeat the Islamic State (ISIS). Ryder did not clarify whether the United States will respond to the latest incidents, stating, “Any response, should one occur, will come at a time in a matter of our choosing.”

Iran’s Terror Network in Iraq and Syria

The Islamic Resistance in Iraq is a network of shadowy Iraqi militia groups affiliated with Iran’s Islamic Revolutionary Guard Corps. “Islamic Resistance” is a euphemism used by Iranian-backed groups to refer to each other, including groups outside of Iraq, such as Hezbollah, Palestinian Islamic Jihad, and Hamas. Since the war in Gaza began on October 7, several Shiite militias have issued direct threats to U.S. interests in Iraq and across the Middle East. The groups, known as Popular Mobilization Units, swear allegiance to Iran’s supreme leader and have killed more than 600 American troops since 2003.

Shiite Terrorist Groups in Syria Attack U.S. Forces,” FDD Flash Brief

Iran-Backed Militias Attack U.S. Forces in Iraq,” FDD Flash Brief

Iran-backed Shia militias target 2 U.S. bases in Iraq,” by Joe Truzman and Bill Roggio


Iran Iran Global Threat Network Iran-backed Terrorism Israel Israel at War Jihadism Military and Political Power Syria U.S. Defense Policy and Strategy