MAKHMOUR, Iraq -- Two years ago, the U.S.-led coalition launched the first airstrikes on the Islamic State group, ushering in a deeper phase of intervention that dramatically changed the fight against the militant group in Iraq. Since then, more than 9,400 coalition airstrikes have allowed Iraqi forces to slowly claw back cities, towns, supply lines and infrastructure.

But the fight -- which continues to be largely waged from the air -- has also levelled entire neighbourhoods, displaced millions and redrawn the Iraqi map.

The U.S.-led coalition estimates that since the airstrikes began on Aug 8, 2014, IS has lost more than 40 per cent of the territory it once held in Iraq. But while coalition airstrikes paved the way for Kurdish and Iraqi ground forces to retake territory, in many cases the result is a ruined prize.

The first coalition strikes were spurred by an IS push from Mosul a few weeks after the group's initial rampage across Iraq.

Makhmour base was just one of a number of front-line positions overrun in early August 2014, bringing IS fighters within just 30 kilometres (19 miles) of Irbil, the capital of Iraq's Kurdish region.

"Daesh was moving into this town and we were withdrawing up into the mountains," said Ayoub Khaylani, a Peshmerga solider who was at Makhmour base with his unit just before the initial IS attack on Mahkmour. Daesh is an Arabic acronym for IS.

After three days of airstrikes, the IS advance on Irbil was slowed and Kurdish forces retook the base. Two years later, the fight against IS has moved west across the Tigris River into Nineveh province and Makhmour has transitioned from an active front line to a sleepy support position.

"If it weren't for the strikes and the heavy artillery (given to the Iraqi army by the coalition), we would still be up in the mountains," Khaylani said, sitting in a small air conditioned room hunched over his mobile phone on an overstuffed sofa.

"I will not allow the United States to be dragged into fighting another war in Iraq," said President Barack Obama when he announced the authorization for airstrikes in Iraq in 2014. "American combat troops will not be returning to fight in Iraq."

On Friday, the Pentagon announced about 400 U.S. soldiers will deploy south of Mosul to Qayarah airbase to aid in the operation to retake Iraq's second-largest city. They are among the 560 additional troops that President Obama approved for the Iraq mission last month. The Pentagon says there are about 3,800 U.S. forces currently in Iraq, not including hundreds who are on temporary duty and not included in the official count.

As the push to retake Mosul ramps up, the scars from two years of costly victories remain vivid.

Sinjar, the small mostly Yazidi town north of Mosul, was retaken by Kurdish forces nine months ago, but it still lies in ruins. While Sinjar is technically "liberated" the vast majority of its residents still live in tented camps for the displaced scattered throughout Iraq's north.

The Pentagon claims 55 civilians have been killed in Iraq and Syria since the air war against IS was launched. However, human rights and humanitarian aid groups insist that number is vastly underestimated. Airwars, a project tracking airstrikes targeting IS, estimates that at least 1,568 civilians have likely died in coalition actions.

For Iraq's Kurdish peshmerga forces, pushing back IS has also meant strengthening their hold on disputed territory. Closely supported with coalition training, intelligence sharing and airstrikes, Kurdish forces have taken hundreds of towns and villages from IS that were previously claimed by both the Kurdish regional government and Iraq's central government in Baghdad.

Amnesty International accused peshmerga forces of deliberately destroying thousands of homes in Arab villages taken back from IS in an effort to prevent Arab residents from returning to the territory, according to a report earlier this year.

Mosul residents who fled to Irbil in the summer of 2014 celebrated the first coalition airstrikes on extremist militants, hoping the stepped-up intervention would quickly repel the militants and allow civilians to return home.

Now, makeshift tents in church gardens and half-finished buildings have been replaced with neat rows of caravans on the outskirts of town that resemble fledgling neighbourhoods more than temporary shelters.

Across Iraq, more than 3.2 million Iraqis remain displaced from their homes, according to information gathered by the International Organization for Migration.

Kindi Hameed Majid, 30, fled Mosul with his wife in the summer of 2014. The young couple thought they would only be gone a few days. Now more than two years later, he is still in Irbil and says he doubts he will ever return.

Even if Mosul is retaken by Iraqi forces, he said he worries the city will never be secure enough to be inhabitable again. "We see the future as dark and unknown."

 

Associated Press writers Balint Szlanko and Salar Salim contributed to this report.