ISIS Resurgence in Iraq: What the US Withdrawal Changes

The latest US troop pullout from Iraq is not just a logistics story. It is a test of whether ISIS resurgence in Iraq is a real danger or a politically useful warning. As American tanks leave Iraqi Kurdistan and the coalition built under Operation Inherent Resolve winds down, the debate is no longer about whether the Islamic State can seize territory tomorrow. It is about whether Iraq‘s security system can keep a dispersed insurgency from exploiting a shrinking US footprint, rising regional rivalry and political fragmentation.

The issue is sharper because this is not the first time Iraq has been told the war is over. After the 2014 collapse of Mosul and the shock of Sinjar, ISIS was beaten back by a combination of Iraqi troops, the Peshmerga, militia formations and US airpower. That coalition broke the group as a proto-state, but not as an underground network. The group traces its lineage to Al-Qaeda in Iraq, and that history matters: it has repeatedly survived by trading banners, hiding in rural belts and waiting for state fatigue.

The drawdown is a security test, not a ceremonial exit

Security withdrawals are often described as symbolic, but symbolism is the least important part of this story. What matters is capability. The presence of United States Armed Forces in Iraq has not only meant visible troops. It has meant intelligence, surveillance and reconnaissance, air support, maintenance, planning, communications and coordination between local partners that do not naturally trust one another. Remove enough of that architecture and the battlefield changes even if the front line does not.

That is why the article’s warning about an ISIS comeback should be read carefully. A resurgence suggests scale, momentum and territorial capture. Iraq’s more likely danger is subtler: an insurgent revival that normalizes low-level violence, taxes local commanders and erodes public confidence in the state. The group does not need to retake Baghdad or even Mosul to matter. It only needs to prove that the government cannot secure roads, farms and borderlands consistently.

The difference between defeat and disappearance matters. A movement that loses cities can still win by making a state spend more money, time and legitimacy than it can sustain.

That is why the drawdown should be assessed as a test of institutional depth. If Iraq can absorb the coalition’s functions, the exit may be manageable. If it cannot, the withdrawal becomes a force multiplier for instability rather than a sign of sovereignty.

Why counting territory misses the point

ISIS was never only a state-like entity. It was also a command culture, a recruitment model and a violence economy. Even after its territorial defeat, it retained the ability to exploit checkpoints, ambushes and gaps in governance. That is particularly true in remote or disputed areas where local populations distrust both central authorities in Baghdad and regional forces linked to the Kurdistan Region. In insurgency terms, the map is less important than the seams.

In practical terms, the threat profile looks like this:

• Rural mobility: small cells can move through less monitored roads and valleys.
• Political distraction: when local forces compete with one another, counterterrorism becomes secondary.
• Grievance recycling: unresolved displacement, detention and corruption continue to feed recruitment narratives.
• Border opportunity: the Iraq-Syria frontier remains relevant because militant networks do not respect state lines; the war next door in Syria still shapes movement, supply and shelter.

Why ISIS still has room to operate

It is important not to exaggerate the organization. ISIS is not waiting with the same force it had in 2014. It is weaker, fragmented and under far more pressure than when it captured Mosul. But weak does not mean harmless. Insurgencies thrive when states underestimate them because their power lies in persistence, not parade grounds.

In Iraq, that persistence is helped by geography and administration. The line between federal control and regional Kurdish control is not simply a border; it is a patchwork of responsibilities, rival command chains and political suspicion. The Iraqi Security Forces and the Peshmerga have both fought ISIS, but coordination has often been imperfect, especially in disputed districts. Those gaps are precisely where a patient insurgency can survive.

There is also a psychological dimension. The collapse of 2014 still shadows Iraqi politics. When a state has once lost large parts of its territory, every reduction in external support is read through that memory. This is why even a managed withdrawal can trigger alarm: officials know that ISIS does not need to replicate the old offensive to produce a political crisis. It only needs to exploit one high-profile failure and turn it into a story of state weakness.

Why experts say Tehran may benefit

The claim that the move will benefit Tehran should be understood as a balance-of-power argument, not a conspiracy theory. Iran does not need to take over Iraq to gain leverage. It only needs less US presence, fewer constraints on its local partners and more room for actors aligned with its interests to shape government formation, security policy and street politics.

That is where the role of the Popular Mobilization Forces becomes central. These forces are a real part of Iraq’s post-ISIS security landscape, but they are also politically sensitive because some factions are close to Iran while others are more nationalist or state-oriented. When US leverage shrinks, the internal balance inside these networks can shift. That does not automatically produce Iranian control, but it can reduce the space for Washington to pressure Baghdad over militia discipline, border security and command unity.

The wider political context matters too. US-Iraq relations have long been shaped by the tension between sovereignty and dependence, a tension reflected in the United States–Iraq Status of Forces Agreement debate and in the recurring argument over whether American troops are a stabilizing partner or a liability. Every drawdown revives that dispute. For Tehran, any reduction in American military access is useful even if Iran does not gain a single extra base.

Baghdad and Erbil are the real fault line

The convoy footage leaving Iraqi Kurdistan is visually powerful because it marks a narrowing of the American buffer between competing Iraqi centers of power. The relationship between Baghdad and Erbil has always been politically complicated, and the security map follows that complexity. In practice, the most vulnerable places are often not major cities but the spaces between them: disputed districts, rural supply lines and neglected checkpoints.

That is where the real cost of the withdrawal will be measured. If the federal government and the Kurdish regional authorities can share intelligence, coordinate patrols and avoid competing chains of command, ISIS will find less room to manoeuvre. If they cannot, the group will not need to win battles to gain relevance. It will simply need to expose the absence of unity.

This is why the article’s emphasis on experts warning that the move will benefit Tehran is only part of the story. Iran gains most when Iraq’s own internal divisions become the main security problem. A divided Iraq invites outside influence. A coordinated Iraq limits it. The challenge is that coordination is politically difficult precisely when foreign forces are leaving and domestic actors are recalculating who will fill the gap.

What a credible Iraqi containment strategy would require

If the US presence continues to shrink, Iraq will need to compensate in ways that are operational, not rhetorical. The country has heard too many declarations of victory that did not survive the next bad season.

• Persistent intelligence sharing: not just battlefield reporting, but analysis that links rural movement, financing and local grievances.
• Joint command clarity: the Iraqi Security Forces and the Peshmerga need clearer division of labor in disputed zones.
• Local legitimacy: communities in and around Mosul and Sinjar need security, services and credible dispute resolution, not just raids.
• Militia discipline: any force tied to the Popular Mobilization Forces must be integrated in a way that prevents parallel authority from becoming permanent.
• Border pressure: the Syria frontier must be monitored as a transit space, not treated as a distant issue.

These are not glamorous measures, but insurgency is not glamorous either. The groups that survive do so by exploiting boring failures: poor maintenance, weak coordination, inconsistent salaries, delayed court cases and unresolved land disputes. That is why counterterrorism success is often less about battlefield heroics than administrative discipline.

Frequently asked questions

Is ISIS back in Iraq?

Not in the territorial sense seen in 2014. The more accurate description is an insurgent presence that remains capable of attacks, intimidation and propaganda. A true comeback would require control of land, population and supply networks, and there is no evidence of that scale today.

Why is the US leaving Iraq now?

The immediate reason is the reconfiguration of the coalition mission after years of combat and advisory activity. The deeper reason is political: Washington and Baghdad have long disagreed about the size, role and permanence of the US military footprint. That tension has been part of the post-2003 order in Iraq.

Does the withdrawal automatically help Iran?

No. It does not automatically hand Tehran a victory. But it can widen the space in which Iran-aligned actors operate, especially if Iraqi institutions remain fragmented and US leverage falls faster than Baghdad can build alternatives.

What is the biggest risk after the drawdown?

The biggest risk is not a dramatic ISIS takeover. It is a quieter security erosion: fewer joint operations, more disputes over who controls vulnerable areas, and a gradual return of fear in places that already lived through collapse once before.

The question that now decides the next phase

The most important insight is that the drawdown will be judged less by whether troops leave and more by what functions survive after they do. If Iraq can preserve intelligence, coordination and rapid response without relying on a large foreign presence, then the exit may become a real sign of sovereignty. If it cannot, then the withdrawal will not end the security problem; it will reorganize it.

The near-term forecast is therefore not a new ISIS state, but a more familiar and more dangerous pattern: scattered violence, political blame-shifting and deeper room for external actors to shape Iraqi choices. That is why the central unanswered question is not whether ISIS can march back into cities. It is whether the Iraqi state can keep its seams from becoming an open invitation. If it fails, the group does not need a capital to matter again. It only needs enough pressure points to prove that the state is still easier to frighten than to defend.