The Pentagon's top war planner said the military campaign's impact remains limited after four days of airstrikes in northern Iraq, and the Islamic militants continue to be a powerful force capable of terrorizing Iraqi civilians and seizing territory.
"I in no way want to suggest that we have effectively contained, or that we are somehow breaking the momentum of [the Islamic State of Iraq and the Levant]," said Army Lt. Gen. William Mayville, the director of operations, or "J-3" for the Joint Staff, told reporters Monday.
"They are very well organized. They are very well equipped. They coordinate their operations and they have thus far showed the ability to attack on multiple axis. This is not insignificant," Mayville said at a Pentagon briefing.
Since President Obama authorized the airstrikes on Aug. 7, U.S. Air Force and Navy aircraft have dropped bombs 14 times, targeting ISIS artillery positions, armored vehicles and convoys.
The U.S. aircraft are providing nearly 24-hour coverage over northern Iraq, dropping laser-guided bombs on ISIL positions when reliable targeting information becomes available, a CENTCOM official told Military Times.
Those aircraft include Air Force F-15E Strike Eagles, F-16 Fighting Falcons, Navy F/A-18 Super Hornets and unmanned MQ-1 drones,. They are flying over Iraq from several locations including the carrier George H.W. Bush and some land-based airfields that military officials are not identifying due to "host-nation sensitivities and operational security," the CENTCOM official said.
Mayville emphasized the limited impact of the operation so far.
"I think in the immediate areas where we have focused our strikes, we have had a very temporary effect ... and we may have blunted some [ISIL] tactical decisions to move in those directions further east toward Erbil," Mayville said.
"However, these strikes are unlikely to affect ISIL's overall capabilities or its operations in other areas of Iraq and Syria," he said.
Obama authorized the airstrikes for two specific purposes. One mission is to prevent an ISIL advance into the city of Erbil where U.S. civilian diplomats and dozens of military advisors are based. The second — and potentially more challenging mission — is to break ISIL's siege of a mountain where an estimated 40,000 Iraqis from the Yazidi minority are trapped and on the verge of starvation.
As part of a humanitarian mission to help those Yazidis, U.S. and British aircraft have dropped more than 300 bundles of food, water and medical supplies over the crisis area. The ISIS forces are reportedly executing large numbers of Yazidi men, and Obama said he fears the Yazidis will face genocidewithout U.S. military help.
Mayville declined to say whether Pentagon planners are considering sending more U.S. ground troops into Iraq. Obama has signaled a strong reluctance to send "combat troops," but experts say ground-level forces, such as forward air controllers, advisers for the Kurdish Peshmerga forces or added intelligence units, would be helpful.
"There are no plans to expand the current air campaign beyond the current self-defense activities," Mayville said.
Any talk of more boots on the ground is "a little bit too speculative ... for where we are right now," he said.
"We are right now gripped by the immediacy of the crisis," he said.
Obama on Saturday warned that the new Iraq mission will take months and that it would be "big mistake for us to think that we can, on the cheap, simply go in, tamp everything down again."
Obama said resolving the humanitarian crisis may require a safe-passage corridor to bring thousands of Yazidis safely through ISIL-controlled territory. Many experts say that will require ground forces and, potentially, major combat. Mayville declined to comment on any planning that may be underway to provide security for a safe-passage corridor.
The ISIL forces surrounding the Yazidis trapped on Mount Sinjar reportedly fired at helicopters that were part of a civilian-led humanitarian relief effort. Mayville said that reflects the force and firepower of the ISIL units holding the siege. "It does not surprise me that there will be small arms fired during the ingress or the egress of those aircraft just because of the way ISIL has formed formations on the ground" he said.
Finding ISIS targets is becoming more difficult as time passes, Mayville said.
"Where they have been in the open, they are now starting to dissipate and to hide amongst the people so the targeting of this those forces that are trying to effect a siege around the mountain, this targeting is going to become more difficult," Mayville said.