WASHINGTON (CNN) -- Two U.S. F/A-18 jet fighters bombed artillery of Sunni Islamic extremists in Iraq on Friday, escalating America's military involvement more than two years after President Barack Obama brought home forces from the country.
Obama authorized "targeted airstrikes" if needed to protect U.S. personnel from fighters with the Islamic State, formerly known as the Islamic State in Iraq and Syria, or ISIS. The U.S. military also could use airstrikes to prevent what officials warn could be a genocide of minority groups by the Islamic State fighters.
U.S. warplanes patrolling the skies over northern Iraq have a "green light" to go after perceived ISIS threats to the Kurdish capital, Irbil, or to minority populations, said deputy national security adviser Ben Rhodes.
The first strike involved 500-pound laser-guided bombs on a "mobile artillery piece" used by ISIS at about 6:45 a.m. ET Friday, Pentagon spokesman Rear Adm. John Kirby said.
It came in response to an Islamic State advance this week on what officials call U.S. interests in Iraq's Kurdish region in the north. The militants took towns from the Kurdish fighting force known as the Peshmerga.
Before the onslaught, the region had been the most stable in Iraq and a cooperative ally of the United States. U.S. military advisers and consular personnel are stationed in Irbil.
The mobile artillery battery hit Friday was based outside Irbil, Kirby said.
In announcing his decision Thursday night, Obama said the militants would get hit "should they move towards the city."
Kurdish leaders have been pleading for the United States or NATO to buttress their forces against the Islamic State from the air. The President seems to have heard their appeal.
"We do whatever is necessary to protect our people," Obama said, adding, "We support our allies when they're in danger."
Obama: Potential 'genocide'
U.S. airstrikes also could hit the Islamic State if militants continue to endanger the lives of thousands of ethnic Yazidis stranded in mountains by the militants' siege. Obama and other administration officials are using the term "genocide" when referring to the threat to the internal refugees.
Last weekend, ISIS militants raided the Yazidi town of Sinjar in northern Iraq. Yazidis, one of Iraq's smallest minorities, are of Kurdish descent and their religion is considered a pre-Islamic sect that draws from Christianity, Judaism and Zoroastrianism.
The Islamic State has executed people who don't share their fanatical interpretation of Sunni Islam and posted videos of their killings to the Internet. "Convert to Islam or die" is the militants' ultimatum to those captured.
They also have beheaded victims and placed their heads on spikes to strike terror in the population, a senior administration official said.
Before Obama spoke Thursday night, two U.S. military cargo planes airdropped 5,300 gallons of water and 8,000 meals onto Mount Sinjar, where some Yazidi children had died from dehydration.
The British government said Friday it would support the U.S. humanitarian effort and planned airdrops of its own.
Meanwhile, the United Nations in Iraq was "urgently preparing a humanitarian corridor to allow those in need to flee the areas under threat," said Nickolay Mladenov, the special representative to the U.N. secretary-general.
He welcomed the "cooperation between the Government of Iraq, the Kurdistan Regional Government and the international community to help prevent genocide and fight terrorism," according to a U.N. statement.
U.S. Secretary of State John Kerry on Friday repeated the administration's concerns about genocide.
The Islamic State's "campaign of terror against the innocent, including the Yazidi and Christian minorities, and its grotesque targeted acts of violence show all the warning signs of genocide," Kerry said Friday during a televised press conference in Kabul, Afghanistan. "The stakes for Iraq's future could not be more clear," and "for anyone who (needs) a wake-up call, this is it."
Concern over U.S. ground troops returning
While he authorized the airstrikes in response to specific threats, Obama made clear he had no intention of sending in ground forces.
"As commander in chief, I will not allow the United States to be dragged into fighting another war in Iraq," the President said.
The administration has put the onus on the Iraqi government, which it has pushed to reform. It wants Iraqi Prime Minister Nuri al-Maliki's Shiite-dominated regime replaced by an ethnically more inclusive government.
Already, the Obama administration is rapidly funneling weapons to Iraqi forces. Factories in the United States are operating seven days a week to produce them, a senior administration official said.
But two Republican senators said in a statement that the President's actions do not go far enough. And the United States should not wait on Iraq to pull together before Washington takes action.
Sens. John McCain of Arizona and Lindsey Graham of South Carolina want to see U.S. forces take the fight to the Islamic State.
"It should include U.S. airstrikes against ISIS leaders, forces, and positions both in Iraq and Syria," their statement read.
Iraqi forces fight back
The Iraqi air force bombed a number of Islamic State targets on Thursday night, said Qubad Talabani, deputy prime minister of the Kurdish regional government. He told CNN the strikes killed at least two of the group's emirs.
At this point, the United States has 245 military personnel in Iraq, 90 of them advisers sent in recent weeks to coordinate with Iraqi and Kurdish military officials in response to the ISIS rampage. The USS George H.W. Bush and other Navy ships also are in the region, and the FA/18s in Friday's initial strike came from the aircraft carrier.
The Islamic State fighters have captured armored vehicles and other military hardware from Iraqi forces in a lightning sweep through the north earlier this year.
The militant group's name, Islamic State, reflects its goal to establish a Sunni caliphate stretching from Syria to Baghdad. After establishing the religious state, the group envisions expanding it throughout the world, and analysts warn of Americans and Europeans with the Islamic State returning home at some point to bring the battle.
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