Washington completes Iraq drawdown, and a security vacuum opens

US troops began pulling out of their last remaining bases in Iraq on Wednesday, finalising a withdrawal first agreed under the Biden administration and leaving behind an uncertain security environment in a country that has endured nearly a quarter-century of war. Iraqi officials, security commanders and analysts warn that the exit could strengthen Iran-backed armed groups and hand Islamic State fighters the breathing space they need to rebuild.

The departure marks a stark anniversary: 23 years after US-led forces toppled dictator Saddam Hussein, setting off the upheaval and institutional collapse that ended in the emergence of Islamic State. Though the pullout is widely welcomed by Iraqis, the departure of American personnel has done little to settle anxieties. Security forces trained and equipped with US funding are still not considered capable of protecting the country on their own — a gap underscored by the fact that 4,500 American service members died in more than 20 years of fighting there.

"The lesson from the past two decades is that security vacuums can be extremely dangerous," said Jassim al-Bahadli, an Iraqi analyst who advises the country's security forces.

The current drawdown closes a chapter in a long, layered US military presence. American forces invaded Iraq in 2003, occupied the country, installed a Shi'ite-led government and then fought a drawn-out counterinsurgency against Saddam loyalists and, later, al-Qaeda affiliates. They withdrew at the end of 2011, when the US formally declared the mission accomplished, only to return less than three years later to help Iraqi forces roll back Islamic State during the major 2014-2017 war.

The human cost of that presence was heavy. Around twice as many Americans were killed in "Operation Iraqi Freedom" as in the parallel war in Afghanistan, which ended with an abrupt US withdrawal in 2021 — a decision many observers have repeatedly warned could invite exactly the kind of instability now feared in Iraq.

The losses have continued well after the troop surge. In this year's conflict with Iran, 18 US service members were listed as killed, seven of them in Iraq. The most recent was an army sergeant who died during the controlled detonation of a drone at a base near Erbil in July.

Tehran is framing the withdrawal as vindication. Iran, which says its overriding objective is to push American forces out of the Middle East entirely, casts the US departure as a win for the "axis of resistance" — the network of allied armed groups across the region. For Baghdad-based political analyst Ahmed Younis, the concern extends well beyond any direct intervention by Tehran. "What is further concerning is not necessarily direct Iranian intervention, but the possibility that Iran's proxies will feel increasingly empowered in the absence of a Western military presence," he said. "These groups may attempt to expand their role in shaping state policies and consolidating their presence within key institutions."

That points to a political risk as much as a military one. Militias that have spent two decades building influence inside state institutions could find that influence harder to check once US leverage recedes.

A parallel warning is coming from Iraqi security officials in both the federal government and the semi-autonomous northern Kurdish region, who say the pullout risks reviving Islamic State. The group was defeated and lost its self-proclaimed caliphate nearly a decade ago, but its sleeper cell network was never fully dismantled, and veterans remain active across the country. At the height of its power the militants occupied a third of Iraq and slaughtered thousands, including hundreds they videotaped themselves shooting dead inside a former US military base.

US troops had been supplying Iraqi forces with intelligence on Islamic State movements, alongside aerial surveillance and reconnaissance — capabilities that are difficult to replicate quickly and that have not been fully handed over. The departure also arrives as other external military arrangements in the region are shifting, with Turkey set to hand over a base in northern Iraq to Baghdad.

The question now is whether Iraq's security institutions have a plan for what comes next. "The most important question now is whether Iraq's security institutions have prepared a viable Plan B for the post-coalition phase," said retired Iraqi Army General Mohammed al-Jubouri, who commanded a brigade in the fight against Islamic State. "One of the worst-case scenarios would be Islamic State obtaining armed drones or improvised explosive drones at a time when Iraq still lacks sufficient air defence capabilities to counter such threats effectively."

The drone warning is not abstract. It echoes a pattern already seen across the region, where the use of cheap, hard-to-track aerial weapons by proxy groups and militants has outpaced the defences available to the states they target.

For ordinary Iraqis, the calculus is less simple than the pullout itself. Leaving bases may end the visible presence of foreign troops and remove a source of resentment, but the withdrawal does not by itself resolve the shortages in personnel, equipment, air defence and intelligence that pushed Washington to send troops in the first place. Whether Iraq's forces can close that gap — before militias or remnants of Islamic State move to fill it — will define the country's next chapter.