Tom Vanden Brook

USA TODAY

ABOARD MILITARY AIRCRAFT OVER THE BERING SEA — The military has sent 130 additional advisers to northern Iraq to plan for the evacuation of refugees under siege by Islamic militants, Defense Secretary Chuck Hagel announced Tuesday.

"This is not a combat boots on the ground kind of operation," Hagel told Marines at Camp Pendleton in California.

The Marines and special operations forces have been sent to the city of Irbil in Kurdish-controlled northern Iraq to assess the humanitarian crisis in the Sinjar mountains and ways to end it, said a senior Defense Department official who spoke on condition of anonymity because he was not authorized to talk publicly about the mission.

USA TODAY earlier reported that the 130 advisers had been sent to Iraq before Hagel's announcement.

There were about 300 U.S. military advisers already in Iraq, as well as other troops there to protect the U.S. Embassy in Baghdad.

The plight of the refugees prompted President Obama to order both airstrikes against the Islamic State militants and humanitarian airdrops there last week. In an interview with USA TODAY on Tuesday, Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, said the military's effort there could take months but will be limited. He added that the effect of the airstrikes had blunted the momentum of the militant group, and shipping heavier arms to Kurdish allies will help solidify the gains.

The survival of the refugees, including members of the Yazidi sect, has been assured for now, Dempsey said, but their fate and rolling back the gains the Islamic State has made — such as seizing the city of Mosul — will require the new Iraqi government to reach out to Sunnis and Kurds.

"The crisis has been abated but not solved," said Dempsey, who is traveling to a series of meetings in Vietnam.

Also Tuesday, Sen. Tim Kaine, D-Va., a member of the Senate Armed Services Committee, called on the White House to seek congressional approval for the airstrikes in Iraq. Kaine supports the humanitarian mission but emphasized that the administration needs congressional authority to continue the attacks.

"This is especially the case since the president has indicated that our renewed military engagement in Iraq could be a long-term project," Kaine said in a statement. "I have long stressed that Congress must formally approve the initiation of significant military action."

In the interview, Dempsey talked about the military's mission in Iraq, the threat from the Islamic State — also known as ISIS or ISIL — and what will be needed to confront it.

He described the Pentagon's role as "limited but I think appropriately so." Its unique capabilities in spy and surveillance aircraft, logistics and targeted airstrikes have filled critical gaps that Iraqi and Kurdish forces could not, he said.

"You hear the term mission creep beginning to make its way around the airwaves," Dempsey said. "What we do is mission match."

Airstrikes in the region won't be needed "in perpetuity" to prevent the slaughter of refugees or to defend Irbil, he said. Instead, the mission could take months.

The threat from the Islamic State has occupied Dempsey — and the Pentagon's attention — for more than a year, he said. Its apocalyptic vision poses a threat, for now, to Iraq and Syria. Unchecked, the group could attack Israel and, ultimately, the United States, he said.

They have successfully co-opted, or coerced, many of the 20 million disenfranchised Sunni Muslims living in Syria and Iraq, he said.

"This is a group with a long-term vision," Dempsey said. "And the long term vision is completely antithetical to any of our values."

Airstrikes have had the effect of ending what has been a long winning streak for the Islamic State, he said. The effect has encouraged Middle East and European allies to offer heavier weapons and training to the Kurds' peshmerga fighters, he said.

"The airstrikes have made it clear both to the Iraqi security forces and to the pesh and to (the Islamic State) that they're no longer uncontested," Dempsey said. "The pace at which they were advancing has been abated. It doesn't mean it will stay abated."

The Kurds will be receiving armor-piercing weapons to attack militant vehicles seized from the Iraqi army, rocket-propelled grenades and heavy machine guns, Dempsey said. He described the effort to arm them as "ongoing" without indicating who was providing the weapons.

Demspey expressed optimism that the new Iraqi government would reach out to Sunnis and Kurds and take on the fight. Earlier this summer, they folded quickly, giving up Mosul without a real fight.

If Iraq does not form an inclusive, effective government, military efforts there won't have a lasting effect.

"Then all we're really doing," Dempsey said, "is painting over the rust."

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