The U.S. military announced Wednesday that it has completed the withdrawal of all American forces from Iraq, ending a 12-year mission that began as a fight against the Islamic State group and evolved into one of the longest-running American deployments in the Middle East.

Pentagon spokesperson Sean Parnell said American troops and equipment completed what the military called an "orderly departure" from an air base near Irbil, in Iraq's semi-autonomous Kurdish region, the last U.S. position remaining in the country. According to ABC News Australia, Parnell said the milestone "reflects the success of a 12-year campaign that defeated ISIS as an organised military threat in Iraq and across the region," and marks a shift "from a wartime coalition mission to an Iraqi-led security effort supported by a more normal bilateral security relationship."

From Invasion to Advisory Role

The pullout closes the book on Operation Inherent Resolve, the coalition mission against ISIS that followed the much larger American military presence in Iraq dating back to the 2003 invasion. PBS NewsHour reported that the Pentagon says targeted training and intelligence support for Iraqi security forces will continue, just without a standing American troop presence inside the country.

Baghdad has cast the withdrawal as proof of Iraq's growing strength and sovereignty after more than two decades of foreign military presence on its soil. Iraqi officials have pointed to the drawdown as validation of a security relationship they say is now built on partnership rather than occupation.

"A TRANSITION FROM A WARTIME COALITION MISSION TO AN IRAQI-LED SECURITY EFFORT"

Kurdish Officials Sound the Alarm

Not everyone in Iraq is celebrating. Kurdish officials in the country's semi-autonomous north have expressed sharp concern over the removal of American air-defense systems that had helped shield the region. Iraq's Kurdish region absorbed more than 1,000 drone and ballistic-missile attacks during the recent period of heightened U.S.-Iran tension, according to regional officials cited in the same reporting, and they worry the departing air defenses leave a gap that Iran-aligned militias or other hostile actors could exploit.

The concern reflects a broader anxiety in the Kurdish region, which has historically relied on U.S. military presence as a check against threats from Baghdad, Tehran-backed militias and, in earlier years, ISIS remnants operating in rural areas near the Iraq-Syria border.

What's Next

U.S. officials say the shift to an advisory relationship does not mean the end of American involvement in Iraq's security, just the end of a standing troop presence. How quickly Iraqi forces can fill the resulting gaps, particularly in air defense, is likely to be the first real test of the new arrangement, especially if regional tensions with Iran flare again in the coming months.