Confronting the Islamic State group in Iraq is the "main" priority for the US-led fight against the jihadists, while strikes in Syria are designed to disrupt the group's supply lines, the US commander overseeing the air war said Friday.
Even with the world's attention fixed on the fate of the northern Syrian town of Kobane, General Lloyd Austin said Iraq was the primary battleground for the air campaign.
"Iraq is our main effort, and it has to be," Austin told reporters.
"And the things that we're doing right now in Syria are being done primarily to shape the conditions in Iraq," he said.
US-led air raids in Syria are serving as a way to undercut the group's ability to reinforce and resupply its fighters in Iraq, he said.
In his first press conference since the air campaign was launched in Iraq on August 8, Austin said it would take time before Iraqi government forces were truly effective and declined to say when the army would be ready to stage major offensives to recapture lost territory in Mosul or elsewhere.
"It's difficult to ...designate a specific point in time when they'll be able to do this."
Iraqi army troops have suffered a string of setbacks in western Anbar province, raising fears that Baghdad could come under pressure and the airport endangered.
But Austin said the airport was not at risk of falling to the IS group.
"I feel fairly confident that the airfield is secure and will be secure for the foreseeable future," he said.
It was possible the IS could fire a mortar round at the airfield, but similar incidents occurred during the US occupation of Iraq in 2003-2011 and did not force the closure of the airport, he said.
"This is something that we monitor -- we patrol on a routine basis," he said, adding that US Apache helicopters, drone surveillance aircraft and Iraqi forces all help guard the airport.
Although defeating IS in Iraq was the top goal, Austin acknowledged US aircraft had been pounding the group's fighters around the Syrian border town of Kobane this week with dozens of bombing raids.
He said the strikes were a response to IS moving in large numbers around the town, making itself vulnerable to attacks from the air.
"Now, my goal is to defeat and ultimately destroy ISIL (IS). And if he continues to present us with major targets, as he has done in the Kobane area, then clearly, we'll service those targets, and we've done so very, very effectively here of late," Austin said.
There have been "encouraging" signs in recent days in the battle over the Syrian border town of Kobane, with US air strikes slowing the advance of Islamic State jihadists, he said.
But he acknowledged the town could still fall to the IS group, despite stiff resistance from Kurdish militia and stepped up US bombing raids.
"It is highly possible that Kobane may fall," Austin said.
"But .. .I think the things that we have done here in the last several days are encouraging. And we're seeing the Kurds actually fight to regain territory that had been lost previously," the general said.
"And I think we've been able to help that along with precision air strikes in the last couple days."