Abandoned cars that ran out of gasoline while fleeing the rapid advance of the Islamic State militants litter the final checkpoint on the highway on Aug. 7, 2014 near Kalak, Iraq. The militants' front lines lie about about one mile down the road from this point.

Abandoned cars that ran out of gasoline while fleeing the rapid advance of the Islamic State militants litter the final checkpoint on the highway on Aug. 7, 2014 near Kalak, Iraq. The militants' front lines lie about about one mile down the road from this point. (Mitchell Prothero/MCT)

Launching airstrikes against Sunni militants in northern Iraq is aimed as much at supporting the Kurdish militia, a staunch U.S. ally for the past two decades, as it is at protecting U.S. personnel and preventing humanitarian disaster, analysts and diplomats say.

The extremist Islamic State group has routed the Iraqi army to seize much of western and central Iraq, including the country’s second-largest city of Mosul. Now, their offensive has brought the militants into striking distance of Irbil, the capital of the semi-autonomous Kurdish region, where dozens of U.S. diplomats and military staff are based.

The surge also has cut off Christian and Yazidi religious communities who relied on Kurdish military protection. In response to the humanitarian crisis and the militants’ move toward Irbil, Obama on Thursday announced that he had authorized targeted airstrikes against the Islamic State group to stop the advance on Irbil.

On Friday, F/A-18 jets dropped 500-pound laser-guided bombs on a mobile artillery piece the militant group was using to shell Kurdish forces defending Irbil, a Pentagon spokesman said.

This contrasts sharply with Washington’s policy to date.

Since the Islamic State offensive started in June, the administration has avoided airstrikes, insisting instead that Iraq’s authoritarian Shiite Prime Minister Nouri al-Maliki must first end the sectarian policies that have driven many Sunnis to support the Islamic State. U.S. officials feared airstrikes would be perceived as America siding with the Shiite-dominated government against a Sunni minority who had legitimate grievances against al-Maliki’s rule.

But the Kurdish region was considered well protected by its peshmerga militia.

Unlike the demoralized, U.S.-trained and largely Shiite Iraqi army, the peshmerga were viewed as a highly motivated force with experienced, battle-tested commanders whose ranks are not riveted with sectarian rivalries.

Thus the latest militant advance into Kurdish territory came as a surprise and galvanized the U.S. to act, a senior Western diplomat with many years’ experience in Baghdad said.

The reason for the U.S. airstrikes “is pretty self-evident — if the peshmerga can’t defend and protect, then they need help,” said the diplomat who could not be named under standing rules.

“Everyone has underestimated (the militants). They are not some ragtag group — they are highly organized, equipped and funded with a strong strategic vision,” the envoy said.

The West may have overestimated the peshmerga’s strengths, said Afzal Ashraf, a fellow at London’s Royal United Services Institute, a military and security think tank.

“The peshmerga are essentially a large militia, not an army,” Ashraf said. “They lack equipment and training.”

“The militants obviously have the advantage of choice where to attack, and they have been able to exploit this (by striking) where the peshmerga were weak.”

The peshmerga were first formed in 1961, when Mustafa Barzani, the father of top political leader Masoud Barzani, revolted against Iraqi rule. Decades of conflict, which claimed the lives of about 100,000 Kurds and included the use of chemical weapons, nearly destroyed the rebels. But after Saddam Hussein withdrew his forces from the area following his defeat in the 1991 Persian Gulf War and the U.S. and its allies set up a no-fly zone over Kurdish territory, the peshmerga have gradually rebuilt their strength. During the 2003 invasion of Iraq, they collaborated closely with U.S. forces.

Since then, the Kurdish region of northern Iraq, which borders Iran, Syria and Turkey, has enjoyed near total independence with its own government, parliament and security force. The region has about 8 million inhabitants, approximately a quarter of Iraq’s total population.

When Islamic State insurgents swept into Mosul and other parts of northern and central Iraq in June, many analysts believed the jihadists would not take on Kurdish security forces. But less than two months later, it has become apparent that the group plans to expand its caliphate — proclaimed across swathes of Syria and Iraq — to include Kurdistan.

Ashraf, a former British air force officer who served in Iraq together with U.S. forces before their withdrawal nearly three years ago, said that, after the start of the militants’ offensive in June, Kurdish forces focused on seizing the disputed, oil-rich city of Kirkuk from fleeing Iraqi government forces. They appeared uninterested in pushing beyond that, effectively allowing fighters of the Islamic State to concentrate on mopping up remaining government forces and consolidating their control elsewhere.

This led to a bitter dispute with the government in Baghdad, which accused the Kurds of seeking to exploit its army’s defeat instead of helping resist the militant surge.

In other areas of Iraqi Kurdistan, Ashraf said, the peshmerga deployed relatively small units to control their region’s borders — stretching 652 miles from the Syrian border in the west to the Iranian border in the east. But that situation changed when the Islamists unexpectedly changed their tactics and attacked peshmerga positions in an attempt to expand their territorial control into Kurdish areas.

“This made it relatively easy to assault Kurdish positions, especially in areas where the peshmerga have been weak,” he said.

After seizing large stocks of Iraqi army weapons, including artillery, tanks and armored personnel carriers, the militants are now more heavily armed than the peshmerga.

“So far, the militants have proved adept at taking advantage of (their) enemies’ divisions … using geography and mobility to mitigate external threats,” the security firm Stratfor said in a report this week.

Analysts said a sustained U.S. bombing campaign could have a debilitating effect on the militants, because the terrain in northern Iraq is open rather than mountainous as in Afghanistan. And relying on motorized transport makes the militants very vulnerable to aerial attack. The insurgents are believed to have only light anti-aircraft cannons, which can be a danger to helicopters or low-flying jets, but cannot reach high-flying U.S. fighter-bombers or drones that have been conducting dozens of reconnaissance flights over the region in recent weeks.

“If U.S. bombing is coordinated with targeting intelligence on the ground and with attacks on the (Islamic State’s) leadership, that would inflict grave damage to the organization,” Ashraf said.

A report Friday by IHS Jane’s, which provides analysis on defense and security issues, agreed that the large convoys employed by Islamic State forces would be vulnerable to attacks from the air. But it warned that U.S. intervention could also hand the militants a propaganda victory by depicting the government in Baghdad as being propped up by Western powers.

“The United States probably considers Islamic State advances into the Kurdistan region to be a red line, given the threat to U.S. investments and the (region’s) role as a potential staging ground for future operations,” the report said.

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