The final coalition departure from Erbil closes Operation Inherent Resolve in Iraq, shifting counter-ISIS responsibility to Iraqi forces while Washington keeps a narrower training and intelligence role.

The United States and its coalition partners formally ended Operation Inherent Resolve in Iraq on September 30, bringing the final troops and equipment out of Erbil Air Base and closing a twelve-year military mission launched after Islamic State seized large areas of Iraq and Syria in 2014. The withdrawal implements a timetable agreed by Washington and Baghdad in 2024 and transfers primary responsibility for counter-ISIS security inside Iraq to Iraqi forces.

Reuters reported celebrations in parts of Iraq alongside concern that the departure could create space for Iran-backed armed groups or surviving Islamic State networks. The Pentagon said the coalition mission had concluded but that the United States would continue targeted training and intelligence support through a more conventional bilateral security relationship.

A mission ends, but the threat picture does not

The most important distinction is between the end of a coalition mission and the disappearance of the threats that created it. Islamic State no longer controls the large territorial holdings it seized a decade ago, but its remnants have not ceased to exist. Iraqi forces must now contain those networks without the permanent coalition presence that supported operations, intelligence and coordination for years.

That transition is exactly what Iraqi officials say they are prepared to manage. Prime Minister Ali Faleh al-Zaidi described the change as a move toward full Iraqi responsibility for security and stability. The challenge will be to demonstrate that the state can suppress terrorist cells while also maintaining authority over powerful armed factions that operate within or alongside Iraq’s formal security structure.

The withdrawal has deep historical weight

The September 30 departure carries symbolic importance because the U.S. military relationship with Iraq has been defined by repeated entry and withdrawal. American forces invaded in 2003, left at the end of 2011 and returned less than three years later after Islamic State swept across northern and western Iraq. Operation Inherent Resolve became the institutional framework for that second intervention.

More than 4,500 U.S. troops died during the broader Iraq war, according to Reuters, while the Iraq Body Count project estimates that more than 200,000 Iraqi civilians were killed. Those figures explain why the final departure is interpreted not simply as a force adjustment but as the closing of a prolonged chapter in Iraqi political and military history.

Baghdad now faces a test of state authority

Iraq’s security challenge is not limited to Islamic State. Iran-backed militias have accumulated military and political influence over many years, and several groups have resisted efforts to place all armed activity under direct state control. Some Iraqis who welcomed the U.S. withdrawal also argued that militias should now surrender weapons to the government so that responsibility for security is clearly located within state institutions.

That question matters because a reduction in foreign military presence can strengthen sovereignty only if domestic authority becomes more coherent. If multiple armed actors retain independent chains of command, the absence of coalition troops may reduce one source of friction while leaving another unresolved.

Iran sees strategic opportunity

Iran and allied groups have long demanded the removal of U.S. forces from Iraq, making the withdrawal a political victory for Tehran’s regional strategy. The current U.S.-Iran conflict adds another layer: Iraq is geographically and politically exposed to the rivalry between the two powers and has strong relationships with both.

That position gives Baghdad incentives to avoid becoming a battlefield for outside confrontation. Yet it also limits the government’s room for manoeuvre. Any attempt to constrain Iran-aligned groups risks domestic confrontation, while a failure to do so can complicate ties with Washington and Gulf states.

Washington is reducing presence, not abandoning the relationship

The Pentagon’s language is deliberately narrower than a complete strategic exit. The end of Operation Inherent Resolve means the wartime coalition mission has concluded; it does not mean intelligence sharing, training or diplomatic-security cooperation ends. Washington intends to maintain a bilateral relationship designed around Iraqi leadership rather than a standing multinational combat mission.

This distinction allows both governments to present the transition in politically useful terms. Iraq can emphasise sovereignty and command responsibility, while the United States can retain channels that help monitor Islamic State and support Iraqi institutions without maintaining the same footprint.

The Kurdish region will watch the transition closely

The final coalition movements were centred on Erbil, in Iraq’s semi-autonomous Kurdish region. Kurdish authorities have historically relied heavily on Western military cooperation, particularly during the fight against Islamic State. The change therefore has a different security meaning in Erbil than it may have in Baghdad or southern Iraq.

Questions will focus on whether Iraqi federal forces, Kurdish Peshmerga units and intelligence services can continue effective coordination against militant cells operating in disputed or remote areas. The quality of those relationships may matter more than the number of foreign troops remaining.

A security vacuum is not inevitable, but it is the central risk

Iraqi analysts quoted by Reuters warned that security vacuums can be dangerous, a concern grounded in the experience of the period before Islamic State’s rise. But the circumstances today are different. Iraqi forces are larger, more experienced and have years of counterterrorism operations behind them. The issue is whether those capabilities can be sustained without the same external support architecture.

Success will depend on intelligence quality, command discipline, local policing and political control over armed groups. None of those factors is captured simply by the physical departure of coalition forces. The withdrawal changes the balance of responsibility; it does not determine the outcome.

The next phase will be judged by Iraqi performance

For Washington, the final withdrawal reduces the exposure of U.S. personnel in a region where American bases have repeatedly been targeted. For Baghdad, it removes a long-running sovereignty dispute. For Iran, it eliminates a military presence it has spent years opposing. Those interests overlap only on the fact of departure, not on what should follow.

The strategic question is therefore straightforward: can Iraq turn the end of a foreign-led mission into stronger national control rather than a redistribution of influence among militias and regional powers? The answer will emerge not from the ceremony marking the exit, but from whether Iraqi institutions can prevent Islamic State’s resurgence, manage armed factions and keep the country from becoming a proxy battlefield in the wider Middle East confrontation.