U.S. military declares end of anti-ISIS Operation Inherent Resolve in Iraq

The U.S. military declared an end to its Iraq-based anti-ISIS operation Wednesday, saying all U.S.-led coalition forces and equipment had been withdrawn from a key base in the north of the country in line with an agreement reached previously with the Iraqi government.

"The orderly departure of Coalition forces and equipment from Erbil Air Base marks the successful conclusion of the military mission that defeated ISIS in Iraq," Department of Defense spokesman Sean Parnell said in a statement. "This milestone reflects the success of a 12-year campaign that defeated ISIS as an organized military threat in Iraq and across the region. It also marks a transition from a wartime coalition mission to an Iraqi-led security effort supported by a more normal bilateral security relationship."

The U.S. military launched Operation Inherent Resolve in 2014 to confront ISIS, the terrorist group that grew out of the remnants of al-Qaeda in Iraq and seized vast portions of Iraq and neighboring Syria in the years immediately preceding the U.S.-led operation. 

Roughly 2,000 Americans were present in Iraq as of February, officials said at the time. By comparison, more than 160,000 U.S. service members were in the country at the peak of the late 2000s "surge" under Operation Iraqi Freedom — a prior mission to topple Iraqi President Saddam Hussein and grapple with a years-long civil war.

As part of the anti-ISIS mission, U.S. troops have served in both Iraq and Syria. The roughly 1,500 troops that had been in Syria for a number of years withdrew earlier this year.

The end of the mission was agreed upon several years ago between the U.S. and Iraq in a plan that prescribed a transition to a more bilateral relationship between the two countries. In the 2024 joint agreement, Iraq and the U.S. announced the end of the multi-country coalition to defeat ISIS by 2025, and the expected end of the Inherent Resolve mission by the end of 2026.

The mission has pushed ISIS from controlling any significant territory, but it doesn't mean ISIS ceases to exist. In December 2025, two U.S. soldiers and a translator were killed in an ISIS attack, according to the U.S. military's Central Command. The U.S. retaliated with airstrikes.

American troops have been targeted by Iran-backed militias inside Iraq in recent years, a threat that has grown more pronounced since the U.S. and Israel jointly launched the ongoing war against Iran. According to the Pentagon, militias affiliated with Iran launched more than 600 attacks against U.S. citizens and facilities between February and April 2026.

Defense Secretary Pete Hegseth addressed the attacks in a July meeting at the Pentagon with Iraqi Prime Minister Ali al-Zaidi, according to a Pentagon readout. They discussed the transition from the Global Coalition to Defeat ISIS to a bilateral relationship, and Hegseth, according to the readout, committed to ending Inherent Resolve by Sept. 30.

Al-Zaidi has promised to disarm the Iran-backed militias in Iraq. He told The New York Times this week the groups are expected to be disbanded by June 2027, after initially setting a September 2026 deadline.

"We expect the Iraqi Security Forces, including the Peshmerga [Kurdish forces] and other security forces in the Iraqi Kurdistan Region, to lead the continuing effort to secure Iraq and keep ISIS remnants suppressed," Parnell said in his Wednesday morning statement, adding that the U.S. military would "continue to provide targeted training and intelligence support to our Iraqi partners."

"The primary responsibility for addressing Iraq's remaining security challenges, including ISIS remnants and Iran-aligned militias that undermine Iraqi sovereignty and regional stability, now rests with the Government of Iraq," he said. "The United States remains committed to counterterrorism and will continue to work with Iraq and our partners to ensure ISIS can never reconstitute from Iraqi territory."

Can Iraq control Iran's proxies?

The formal end of the U.S. military deployment in Iraq that began with the 2003 invasion was celebrated by the government in Baghdad, which declared Sept. 30, "Sovereignty Day." This year, it will begin a three-day national holiday, and the government has called for nationwide celebrations.

Videos circulated widely on social media Wednesday showed military convoys transporting U.S. equipment out of the Erbil base.

Speaking to the national Iraqi News Agency, Sabah al-Numan, a spokesperson for the prime minister, insisted that the nation's security forces were fully capable of maintaining peace and stability across the country.

But the long-planned U.S. withdrawal comes at a highly volatile moment for Iraq and the region. With the U.S.-Iran war at a critical juncture as President Trump warns of possible new strikes despite furtive diplomacy, many Iraqis remain deeply concerned about a potential resurgence of extremist groups in the country, as well as the expanding influence of the Iran-backed militias that have long held significant power in parts of Iraq.

Despite the government's public optimism, several religious and ethnic minority groups harbor serious doubt about the central government's ability to keep those forces in check on its own.

"The majority of Iraqis doubt the ability of the security and military apparatus to maintain security in the country, whether regarding the prevention of external aggressions and attacks or internal movements by armed groups operating outside state control of the government," journalist and regional political analyst Saman Noah told CBS News on Wednesday. 

That is "especially true given that experience has proven the government's inability to subject these [Iran-backed] groups to state decision-making, control their behavior or hold their members accountable," he said. 

Noah said some of the concern stemmed from the Iraqi government's lack of adequate air defenses "to protect the country's airspace, as well as the reliance on American weaponry — whose maintenance, and consequently operation, could cease in the event of any dispute."

Those concerns have only been heightened by the government's failure to meet its own initial deadline to disarm the Iran-backed factions, and concern that such groups could draw Iraq into the broader regional conflict in support of Tehran.

The Kurds in Iraq and their Peshmerga forces have been close allies of the United States since the first Gulf War in 1991, partnering on numerous occasions over the past 35 years. They joined the U.S.-led international coalition to depose Saddam Hussein's regime in 2003, and more than a decade later they fought with coalition forces to deprive ISIS of its massive foothold in the region. 

They have become increasingly concerned about Iraq's future and the prospect of Iran-allied militias seeking to expand their influence.

"We fought side by side with our American allies to bring peace and stability to the region," said Noreldin Waisy, a senior adviser to the Kurdistan Regional Government's prime minister. "To eliminate any doubt among the Kurdish people, we believe the Kurdistan Region must remain an essential part of the bilateral Memorandum of Understanding between the two countries."