Islamic State fighters were on the run in northern Iraq on Sunday after Iraqi and Kurdish forces, backed by US airstrikes, closed in on a strategically vital dam in the most significant attempt yet to reverse the militants' blitz through Iraq.
Iraqi and Kurdish commanders claimed to be making swift progress, slicing through a series of villages and then reaching the dam after a wave of US attacks in which fighter jets, drones and bombers pummeled the extremists' positions.
It was the biggest offensive since the latest US intervention in Iraq was announced 10 days ago, and it signaled an expansion of what was originally defined as a narrowly focused mission to protect American personnel in Iraq and help fleeing Yazidi villagers trapped on a mountain.
In a letter released Sunday notifying Congress of the action, President Barack Obama said the militants' control of the dam posed a threat to the US Embassy 200 miles away in Baghdad, which could be inundated if the dam were breached.
"The failure of the Mosul Dam could threaten the lives of large numbers of civilians, endanger US personnel and facilities, including the US Embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace," he wrote.
Obama had signaled in a statement last week that protecting "critical infrastructure" would be part of what officials have described as a limited military intervention. This was, however, the first time Iraqi, Kurdish and US forces had come together to launch a major ground assault.
A week ago, US airstrikes helped clear Islamic State positions, enabling Kurdish fighters to retake two small towns south of the Kurdish capital, Irbil. That marked the Kurds' first successful effort to recapture territory they had lost to an Islamic State offensive launched two weeks ago.
Kurdish and Iraqi officials said that Sunday's operation was going better than expected and that the dam would soon be under full government control. "We expect to finish this within hours," said Helgurd Hikmat, a spokesman for the Kurdish forces, known as the peshmerga.
A US official, who spoke on the condition of anonymity because of the sensitivity of the situation, also said that the operation had "made significant progress". But he said that recapturing the dam would take time "because there are a lot of IEDs," or roadside bombs.
Late Sunday night, a senior Kurdish official said that Islamic State fighters had abandoned their positions at the dam but that Iraqi and Kurdish forces had refrained from entering the facility because of concerns that it was booby-trapped.
"Everybody is being really careful about their sinister tactics. When they leave their positions, they mine them," said Hoshyar Zebari, a former Iraqi foreign minister who is working closely with the Kurdish government.
"But we don't see any resistance whatsoever."
The Islamic State's August 7 capture of the Mosul Dam, just hours before Obama announced his decision to send USwarplanes back into action in Iraq, was a high point in the group's campaign to establish a caliphate across the Middle East, putting the militants in control of one of Iraq's most vital facilities.
Ten days on, it seemed that the intervention was starting to turn the tide.
At the Badriya checkpoint, six miles north of the dam, spirits were high among peshmerga troops blocking the road ahead, citing the danger posed by explosives planted by the retreating militants. Several Islamic State fighters had been captured trying to sneak through Kurdish checkpoints in a bid to escape, said Yunus Said, a volunteer fighter. Others had retreated to the western bank of the Tigris River, he said.
As he spoke, a convoy of SUVs and armored vehicles sped past from the direction of the front line, escorting a pickup in which a bound, blindfolded captive sat.
The soldiers cheered. "Daish," they shouted, using the Arabic acronym for the Islamic State. "Beat them, beat them."
Iraq's elite special forces, which worked closely alongside US Special Forces units before US troops withdrew in 2011, took the lead in the fighting around the dam, while peshmerga troops closed in on the surrounding villages from the north. Brigade General Abdulwahab al-Saidi, a commander with the Iraqi special forces, said the Iraqi air force and SWAT teams also were involved.
Their advance was preceded by the most intense US bombardment yet, with 14 airstrikes destroying armed vehicles, Humvees, armored personnel carriers and a checkpoint belonging to the militants, according to US Central Command statements. The strikes followed nine in the area the previous day. Three more were carried out later Sunday.
The assault was the worst setback for the Islamic State since the militants embarked on their stunning rout of the Iraqi army across northern Iraq in June. The group has since continued to expand across Iraq and Syria.
The extremists also came under pressure in Syria on Sunday, with activists in their northern stronghold of Raqqah reporting 23 bombing raids by Syrian government warplanes against Islamic State targets there. The Britain-based Syrian Observatory for Human Rights said there were 84 Syrian airstrikes Sunday, an unusually high number. Of them, 43 were against the Islamic State, signaling a significant escalation of Syrian attacks against the group, which the government had for many months steered away from confronting.
On Sunday, two US officials said that the Obama administration had agreed to requests from the Iraqi government to help its forces retake control of the dam because of its strategic importance.
If breached, the dam would unleash catastrophic flooding across a vast swath of territory as far south as Baghdad. But Kurdish and US officials said fears that the militants would blow it up have been overstated. Among other things, it would be difficult to assemble enough explosives to do so.
Moreover, said Brigade General Azad Hawezi, a senior Kurdish commander, "they would flood themselves first, because the first place that would disappear would be Mosul," the biggest city controlled by the Islamic State immediately south of the dam.
However, US officials have said that the dam was poorly constructed and requires constant maintenance and upkeep — something Islamic State fighters would be unable to provide, heightening the risk of failure over the long term.
If the dam were to remain in the hands of the Islamic State, "it could have tremendous humanitarian impacts on the country," said a senior US defense official, speaking on the condition of anonymity to discuss ongoing military operations. "Having them in control of the dam is threat enough."
In a statement, US Central Command said the airstrikes Sunday were carried out by a mix of fighter jets, armed drones and bomber aircraft.
The statement did not identify the type of bombers involved, but the Air Force has B-1 bombers based in the Persian Gulf at al-Udeid Air Base in Qatar. It is thought to be the first time that bomber aircraft have been involved in the Iraqi air campaign. Fighter jets involved in the attacks have largely come from the USS George H.W. Bush, an aircraft carrier deployed to the gulf.
No US troops or military advisers are embedded with Iraqi or Kurdish forces, according to American officials, although about 70 US troops are based at a joint operations center in Irbil.
-The Washington Post