U.S. warplanes and drones struck artillery and military vehicles of a militant Islamist group Friday in an effort to halt its advance toward this booming northern Iraqi oil center, now clogged with displaced people sheltering at churches, factories and construction sites.
The first U.S. military action in Iraq in the nearly three years since the last American combat troops left the country came just hours after it was authorized by President Obama, and appeared to reassure people in the capital of the semiautonomous Kurdistan region.
Residents described a sense of panic in recent days as fighters of the Islamic State, an offshoot of Al Qaeda that now controls large stretches of Iraq and neighboring Syria, pushed to within about 25 miles of Irbil.
But on Friday, even as U.S. officials said Predator drones and F/A-18 warplanes struck mobile artillery and mortar positions and a seven-vehicle convoy, traffic was brisk along the main streets of the city of 1.5 million. Cafes and shops were doing good business.
"Once people realized the Islamic State wasn't coming here, things seemed to get back to normal pretty quickly," said a lawyer close to Kurdish governing circles.
Obama announced late Thursday that he had authorized airstrikes to protect about 100 U.S. military advisors in Irbil, halt the militants' advance and prevent a potential slaughter of minorities including Christians, Shiite Muslims and Yazidis, the latter adherents of an ancient religion related to Zoroastrianism.
Tens of thousands of Yazidis who fled the militants are trapped on a barren mountain, and U.S. cargo planes dropped food and water to them. U.S. Defense Secretary Chuck Hagel said in New Delhi that 60 of the 72 crates dropped on Mt. Sinjar early Friday had reached those needy people.
Another airdrop was made Friday night, the Pentagon said. It included 28,224 meals and more than 1,500 gallons of drinking water, according to a statement from the Defense Department.
Fighters with the Islamic State, feeding on anger among Sunnis over their treatment by the Shiite-led government of Iraqi Prime Minister Nouri Maliki, took control of large pieces of northern and western Iraq in June, including Mosul, one of the largest cities in the country. They seized U.S.-supplied weaponry and vehicles as Iraqi army units disintegrated or fled. The army and Shiite militias have managed to halt the militants' advance outside Baghdad, the capital.
The group also controls about a third of Syria.
Pushing forward under their black flag, the militants have managed to rend a delicate tapestry of cultures and religious beliefs that survived in northwestern Iraq even amid the civil war during the U.S.-led occupation.
The front line composed of Kurdish peshmerga forces, long considered among the best in Iraq, had been stable until days ago when Islamic State fighters began a rapid advance. Thousands fled for their lives.
"We had no doubt that we would die if we did not leave our homes," said Ali Akbar, 58, who was interviewed at an abandoned cement plant outside Irbil that was housing thousands of Shiite Turkmens from the city of Tall Afar, which was overrun in June. "Only the Sunnis remained. We had lived together all our lives. We thought they were our brothers."
A former resident of the city of Sinjar who fled with his wife and six children this week said Islamic State fighters in large military convoys and brandishing heavy weapons entered the town, killing men, tearing babies from their mothers' arms and throwing them from car windows.
"I saw it with my own eyes," said the man, who identified himself only by his first name, Khalas, out of concern for his safety. "I saw the bodies in the streets."
He said in a telephone interview that his family remained on the mountain for two days and that as food ran out, small groups of young men sneaked down into villages at night to forage. The trek sometimes took six hours, and several of the men were killed, he said.
On Wednesday, Khalas said, his family and about 50 others traveled in a convoy down the mountain, dividing into groups of 10 or so in case one group was caught. They were able to cross the Syrian border, and then move back into Iraqi Kurdistan.
Yazidis fleeing the Islamic State advance said they had heard reports of women being seized by fighters as wives, or taken to Syria and sold.
A senior U.S. military official, who spoke on condition of anonymity, said the U.S. believed it could deter Islamic State fighters from trying to enter Irbil and that there were no plans to evacuate American personnel.
Two F/A-18 warplanes dropped 500-pound laser-guided bombs on a mobile artillery piece being used by the militants early Friday.
A missile launched by a U.S. drone struck a mortar position outside the city in late afternoon, said Rear Adm. John Kirby, the Pentagon spokesman. When fighters returned to the site moments later, "the terrorists were attacked again and successfully eliminated," Kirby said.
A little over an hour later, four F/A-18 fighter jets bombed a convoy of seven vehicles and a mortar position, he said.
"The aircraft executed two planned passes. On both runs, each aircraft dropped one laser-guided bomb, making a total of eight bombs dropped on target, neutralizing the mortar and convoy," Kirby said.
The Pentagon provided no details on how many militants were killed or wounded in the attacks.
White House Press Secretary Josh Earnest would not provide a time frame for the bombing campaign, but he offered a "specific presidential commitment" that it would not take place over an extended period.
"The president is determined to make sure that the United States is not dragged back into a long military conflict in Iraq," Earnest told reporters.
In addition to protecting U.S. personnel and assisting Iraqi religious refugees stranded on Mt. Sinjar, Earnest added a third justification for Obama's decision to authorize limited airstrikes. The White House has been encouraged by Baghdad's steps toward a more inclusive government, Earnest said, and believes that the U.S. attack on the Sunni insurgents supports that progress.
"It is, after all, in the clear national security interests of the United States for there to be a stable Iraqi government that can preside over a stable Iraq and a security force that has the necessary capability to address the security situation in that country," Earnest said.
In Irbil, columnist Ako Mohammed of the Rudaw news site said U.S. involvement meant that despite their territorial losses in recent days, Kurds would triumph over the militants. "Obama's speech and the promise of air superiority in the fight mean that Kurdistan will win the war against the Islamic State," he said.
But some wondered what had taken so long.
"Why didn't the Americans do this sooner?" asked Yasser Azis, 42, a Christian and restaurant worker who had fled to the relative safety of Irbil. "This has been going on for months."