U.S. Troops Leave Iraq After 20 Years, Testing Baghdad’s Grip as Iran and ISIS Watch
The last U.S. forces are set to leave Iraq by September 30 under a 2024 deal, ending a deployment that cost 4,500 American lives and reshaped Middle East power balances. Their exit hands more responsibility to Iraqi forces while opening space for both Iran-backed militias and a possible ISIS resurgence.
Iraq is about to cross a line it has never faced in the post‑2003 era: managing its own security without any American troops on the ground.
By September 30, the remaining U.S. forces are due to depart under an agreement reached in 2024 during Joe Biden’s presidency. The pullout brings to a close more than two decades of deployment in which 4,500 American service members were killed, a figure already being compared to the U.S. toll in Afghanistan and used inside Iraq by factions claiming victory over a foreign occupier.
Iran‑aligned groups are among those claiming that victory most loudly. Militia and political leaders close to Tehran have long pressed for a full U.S. exit and now present it as proof that sustained pressure can drive American forces out of the region. Iraqi officials warning of a potential Islamic State (ISIS) resurgence are therefore swimming against a strong current of domestic and regional messaging that casts any foreign military presence as illegitimate.
For ordinary Iraqis, the consequences are far more practical than symbolic. In many areas, particularly in the north and west, local communities still rely on a delicate mix of Iraqi army units, federal police, intelligence services, and Kurdish Peshmerga to watch for ISIS cells and prevent the group from rebuilding rural havens. U.S. forces have not been front‑line combatants for years, but they’ve provided air support, advisors, and surveillance that Iraqi units cannot easily replace.
The departure changes calculations for those forces overnight. Commanders will have fewer options for precision airstrikes, real‑time intelligence, and high‑end logistics. That gap can be partly filled by Iraq’s own capabilities and by cooperation with partners such as the anti‑ISIS coalition’s European members, but those arrangements are less structured once U.S. troops are gone. In disputed territories where security lines between Baghdad and Erbil remain contested, the absence of an American balancing presence raises the risk of local miscalculation as much as insurgent attack.
Strategically, the vacuum is likely to be contested by two actors: Iran and ISIS. Tehran has spent years building influence through political allies and armed groups that are formally part of the Iraqi state security architecture yet respond to parallel chains of command. With Washington’s military footprint removed, those networks will have more room to shape Iraqi decisions on everything from energy deals to aviation links with Iran.
ISIS, though territorially defeated, still benefits whenever central authority weakens. The group has shifted to lower‑intensity ambushes, roadside bombs, and racketeering in remote areas. Its leaders will view the U.S. exit as an opportunity to test outlying Iraqi units, target local officials, and probe whether the intelligence picture around their movements has become less precise.
The change also feeds into wider regional signaling. Iran’s leadership has suggested that if its own security and oil exports are constrained, no regional infrastructure should be considered safe. In that environment, the loss of a U.S. tripwire in Iraq may embolden attacks on American interests elsewhere in the Gulf while giving Iran‑aligned factions in Iraq more leverage to threaten their own government, as seen in recent rhetoric against Prime Minister Ali Faleh Zaidi over compliance with U.S. aviation sanctions on Iran.
For Washington, the exit fulfills a long‑promised objective of ending combat‑adjacent deployments in Iraq, but it does not remove U.S. stakes in the country’s stability. American intelligence, air assets based in the region, and economic tools will remain engaged, only at greater distance and with less day‑to‑day situational awareness.
Key indicators in the coming months will include the level and sophistication of ISIS attacks, the degree to which Iran‑backed groups move against Iraqi government decisions they dislike, and whether Baghdad can sustain security coordination with Kurdish and Sunni partners without an American mediator. Those trends will show whether this withdrawal marks a stable new phase or the start of another cycle of crisis.
Sources
- OSINT