Tom Vanden Brook

USA TODAY

WASHINGTON — Gen. Martin Dempsey, the military's top officer, told a Senate panel Tuesday he will recommend putting U.S. troops on the ground in Iraq to advise Iraqi security forces in their fight against the militant Islamic State group if needed.

Dempsey also acknowledged that the top U.S. commander in the region had already requested that U.S. commandos direct airstrikes from the ground but had been denied. Dempsey's testimony showed the challenges of fighting the war without U.S. combat troops on the ground — a red line that President Obama drew last week when he announced the expanded mission.

"To be clear, if we reach the point where I believe our advisers should accompany Iraqi troops on attacks against specific ISIL targets, I will recommend that to the president," said Dempsey, the chairman of the Joint Chiefs of Staff.

Meanwhile, the House is on track to approve a resolution Wednesday authorizing the president's plan to train and arm Syrian rebels to fight the militant group, also known as ISIL. The resolution includes no new funds to carry out the mission, likely to cost $500 million, and it is expected to pass with bipartisan support.

At the Senate hearing, Defense Secretary Chuck Hagel said the fight with the Islamic State will be complicated and require a regional approach.

"We are at war with ISIL, as we are with al-Qaeda," Hagel said. "But destroying ISIL will require more than military efforts alone. It will require political progress in the region, and effective partners on the ground in Iraq and Syria."

That war continued to widen Tuesday as U.S. warplanes pounded ISIL targets southwest of Baghdad. They destroyed trucks, anti-aircraft artillery and boats on the Euphrates River that were resupplying fighters. Until Monday, those combat sorties had been restricted to targets in northern Iraq.

Dempsey said U.S. advisers could be called on to get closer to the fight if Iraqi security forces undertake a complex operation such as retaking the city of Mosul, the nation's second-largest city.

He added that Gen. Lloyd Austin, the leader of Central Command, had sought U.S. commandos for the battle to secure Mosul Dam but was convinced that they were not needed.

The White House and Pentagon sought later to clarify Dempsey's remarks. They did not represent a change from Obama's position, White House spokesman Josh Earnest said.

"As was clear from Gen. Dempsey's remarks, he was referring to a hypothetical scenario in which there might be a future situation in which he might make a tactical recommendation to the president as it relates to the use of ground troops," Earnest said.

The military is supposed to develop a range of contingency plans, Earnest said, and that was what Dempsey was talking about. But Earnest added, "The president does not believe that it would be in the best interest of our national security to deploy American ground troops in a combat role in Iraq and Syria. That policy has not changed."

Dempsey and Hagel appeared before the Armed Services Committee to outline Obama's plan to fight the Islamist militants.

Hagel said, if unchecked, the Islamic State "will directly threaten our homeland and our allies." However, U.S. intelligence agencies have not detected specific plots by ISIL against targets in the U.S., Hagel said.

The offensive, led by U.S. airstrikes, includes bolstering Iraqi security forces and training moderate Syrian opposition forces.

"The new, broader air campaign will include strikes against all ISIL targets and enable the Iraqi security forces — including Kurdish forces — to continue to stay on the offensive and recapture territory from ISIL and hold it," Hagel said.

Sen. James Inhofe, R-Okla., the ranking member of the committee, said Obama had downplayed the threat from ISIL to the U.S. homeland. His strategy is "fundamentally detached" from the dire situation, he said.

"It will take an army to beat an army," Inhofe said.

A key part of the Pentagon's $500 million plan would train, equip and resupply 5,400 fighters in Syria per year, Hagel said.

The equipment would initially include small arms, vehicles and other equipment, Hagel said. If the forces prove to be effective fighters, they will be provided increasingly sophisticated weaponry. The opposition forces would be carefully vetted before they receive training and weapons.

The Pentagon has bolstered its own forces in Iraq in recent weeks. In all, there are about 1,600 U.S. personnel there. Obama ordered 475 of them last week, including advisers, a headquarters group and more troops to support spy plane missions.

Contributing: Susan Davis

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