US troops leave Iraq after 23 years, handing Baghdad a sovereignty milestone — and a security test

On September 30, 2026, the last 2,500 US troops in Iraq completed their withdrawal, ending more than two decades of American military presence that began with the 2003 invasion that toppled Saddam Hussein. Prime Minister Ali al-Zaidi marked October 1 with a declaration that it represented "a new day in the course of the Iraqi state, with the country free of any foreign military presence and the completion of national sovereignty over its territory." To commemorate what Baghdad is calling Independence Day, the government announced four official public holidays.

September 30 will be the fixed and final date for ending the military mission of the Global Coalition to Defeat ISIS in Iraq and completing the departure of its forces. October 1 will mark a new day in the trajectory of the Iraqi state, as Iraq will be free of any foreign military presence … [The move] represents an essential prerequisite for moving Iraq into a new phase of development and prosperity.— Office of Prime Minister Ali al-Zaidi

The departure closes out Operation Inherent Resolve (OIR), the US-led coalition mission launched in 2014 after ISIS seized nearly a third of Iraqi territory. It fulfills a 2024 bilateral agreement between Washington and Baghdad, and aligns with the Trump administration's stated goal of reducing US military engagement in the Middle East. But the choreography of the exit — celebrated in Baghdad as a sovereignty triumph — obscures a set of unresolved crises that will define whether the transition holds.

The most immediate security concern is the removal of US Patriot air defense batteries from Erbil, capital of the semi-autonomous Kurdistan Region. After the US-Israel war with Iran broke out in February, those systems shot down roughly 95 percent of the drones and missiles that Iran and its Iraqi militia allies directed at targets inside Kurdish territory, the Soufan Center reported. With those batteries gone, Kurdish leaders have already called on Baghdad for protection — from a federal government they describe as an unreliable and sometimes openly hostile partner.

It is unlikely that the Iraqi state is currently capable of defending its skies against Iranian missiles and drones if Iran targets Erbil, for example … Who can stop this Iranian threat if there is no direct understanding with the government in Tehran?— Hassan al-Barari, international relations professor, University of Jordan

On Monday, Kurdish officials in Erbil reported that three Iranian-made drones targeted a camp affiliated with Iran's Kurdish opposition, though responsibility was not independently confirmed, according to DW. The timing underscored the vulnerability experts have warned about.

Among the assets changing hands is a diplomatic and logistics hub at Baghdad International Airport, which is being transferred to the Iraqi government as part of the withdrawal. US officials have confirmed that a small residual force will remain to help Baghdad combat ISIS remnants and other threats, but have not publicly clarified troop levels or rules of engagement, according to the Soufan Center.

The militia disarmament problem is the other unresolved fault line. Al-Zaidi had originally linked the end of the US mission to bringing all armed groups under state control by September 30. That deadline has now been pushed to June 30, 2027. Under the updated framework, armed groups would halt attacks for 90 days in return for guarantees that US forces would leave them alone, after which weapons would be handed over incrementally. But Kata'ib Hezbollah, Harakat al-Nujaba, and Kata'ib Sayyid al-Shuhada — the most unyielding factions — have shown no sign of laying down their arms and have kept up their attacks, the Atlantic Council reported.

Many political movements are associated with armed organizations, so it is hard to see a revolution in the security sector happening any time soon. Even next year, many armed groups will continue to remain free of the central government.— Renad Mansour, deputy director for Middle East and North Africa, Chatham House

Al-Zaidi this week reiterated that nonstate armed groups must disarm or face terrorism charges, but analysts note that key positions in Iraq's defense and interior ministries remain vacant — the very institutions central to any disarmament plan, according to Al Jazeera.

Iran and its allied Iraqi militias have framed the US departure as a victory for the 'axis of resistance,' a framing that reflects nearly five decades of Iranian strategic doctrine aimed at reducing the US footprint in the region, according to the Atlantic Council. Yet one Atlantic Council analyst argues the withdrawal's significance for the broader US-Iran conflict is limited: it removes one near-term option for Iran — using Iraqi militias to fire on US troops during peacetime — but does little to reshape the wider war.

For the Kurds, the departure also reshapes the Turkish dimension. Last week, Ankara and Baghdad reached a deal for the gradual handover of Turkey's military base in the northern Iraqi town of Bashiqa to Baghdad's control; the agreement came out of a meeting between al-Zaidi and Turkish President Recep Tayyip Erdogan on the sidelines of the UN General Assembly. According to the Soufan Center, al-Zaidi's office said the two leaders also agreed on "fully establishing state authority in Sinjar and ending the presence of outlawed foreign armed elements" — language that refers to PKK-linked fighters operating in the mountainous Sinjar region.

A separate milestone also expired on September 30: a 2022 memorandum of understanding between the US and the Kurdistan Regional Government (KRG). Under it, responsibility for paying the salaries of the Kurdish Peshmerga forces had already shifted to the Iraqi federal government. The MOU also mandated merging the Peshmerga's party-aligned units — primarily those of the Kurdistan Democratic Party and the Patriotic Union of Kurdistan — under a single ministry. Kurdish leaders formally inaugurated that merger ahead of the deadline, with KRG President Nechirvan Barzani describing the unified force as 'part of the Iraqi national defense system,' according to the Soufan Center.

Beyond security, al-Zaidi has worked to reframe Iraq's relationship with Washington around economics. In July he traveled to Washington, and at last week's UN General Assembly he outlined ambitions for Iraq to become "an effective economic power in the region" and a "global hub for energy production," pointing to plans to increase crude output and expand refining and petrochemicals. Following his July meeting with al-Zaidi, US Defense Secretary Pete Hegseth said the two had talked about how "a sovereign, stable and strong Iraq would pave the way for mutually beneficial commercial and defense cooperation," and noted that forging a normal bilateral defense relationship "requires a secure environment free from terrorist coercion," according to DW.

For Baghdad, the political aim will be now to make clear that Iraq wants to remain an ally of the US.— Renad Mansour, deputy director for Middle East and North Africa, Chatham House

Former US diplomat Marlin Hardinger told Al Jazeera that Washington will remain engaged through counterterrorism and intelligence efforts centered on the US embassy and consulate, and predicted the Trump administration would focus more on the economic dimension. He cautioned, however, that "the region has become less stable and more turbulent than it was when negotiations and discussions related to the withdrawal of American forces began."

Whether the transition holds will depend on al-Zaidi's ability to consolidate state authority over armed groups, fill the air defense gap left by departing Patriot batteries, and convince Washington to sustain a bilateral defense relationship even without boots on the ground. The Atlantic Council's former US ambassador to Iraq, Alina Romanowski, put it plainly: a departure seen as abandonment could echo across the region. She framed the central challenge as whether al-Zaidi can persuade the United States to remain committed to building a bilateral defense relationship "… while he buys more time to establish control over the militias that continue to resist disarmament."

Why it matters — The US exit ends the military architecture that has shaped Iraqi and regional security for 23 years, leaving an immediate air defense gap over Kurdish territory, Iran-backed militias still armed and active, and an Iraqi government that must now prove it can hold the country together without American troops as a backstop.

Reported by reuters.com, scmp.com, aljazeera.com, thesoufancenter.org, moneycontrol.com, atlanticcouncil.org, dw.com