President Barack Obama's strategy to combat Islamic State extremists in Iraq and Syria is being scrutinized in Congress, where the expanded military campaign has broad support but faces skepticism rooted in more than a decade of war.
Defense Secretary Chuck Hagel and Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, were scheduled to testify Tuesday before the Senate Armed Services Committee, the first in a series of high-profile Capitol Hill hearings that will measure the president's ability to rally congressional support.
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Obama last week outlined his military plan to destroy the extremists, authorizing U.S. airstrikes inside Syria, stepping up attacks in Iraq and deploying additional American troops, with more than 1,000 now advising and assisting Iraqi security forces to counter the terrorism threat. The U.S. conducted the first of the airstrikes Monday, going to the aid of Iraqi security forces who were being attacked by enemy fighters.
The president said he had the authority to order the airstrikes without new congressional approval. Obama did ask Congress to authorize a program to train and arm vetted Syrian rebels battling the Islamic State group and forces loyal to Syrian President Bashar Assad, a program that got a boost Monday as House Republicans pushed to authorize the mission.
Still, there were doubters.
"I support the president 1,000 percent on air support. I do not support the training of Syrian rebels," Sen. Joe Manchin, D-W.Va., a member of the Armed Services Committee, said Monday. His reservations stemmed from the "eight years, $20 billion to train" the Iraqi forces after the U.S. invasion in March 2003. "See what the outcome was there," he said.
Another member of the committee, Sen. John McCain, R-Ariz., questioned the administration's resolve.
"How serious are we? We could have bombed Syria yesterday. We could have taken out ISIS. I can point out to them targets on a map," McCain said Monday. The Islamic State group is sometimes called ISIS or ISIL.
Racing to finish its work and leave Washington for midterm campaigning, House Republicans finalized legislation to authorize the mission to arm and train moderate Syrian rebels.
The authorization under consideration likely will be included as an amendment to a spending bill Congress must pass to keep the government open until mid-December. That would give lawmakers the opportunity to hold a separate debate and vote on the matter - something members of both parties want.
The House Rules Committee voted late Monday to have six hours of debate on the amendment, once it is taken up, with a vote possible as early as Wednesday. House Republicans planned to meet Tuesday to discuss the legislation.
Bowing to congressional fears that any vote is tantamount to a war vote, the legislation includes a provision stating that "nothing in this section shall be construed to constitute a specific statutory authorization for the introduction of U.S. armed forces into hostilities or into situations wherein hostilities are clearly indicated by the circumstances."
The provision reflects a congressional divide between hawks seeking tougher action than that proposed by Obama and lawmakers weary from more than a decade of U.S. wars in Iraq and Afghanistan.
The measure compels the Pentagon to present Congress with a plan 15 days before any training begins and requires ongoing updates every 90 days. The administration isn't likely to protest the conditions.
The U.S. plan is to develop moderate Syrian forces at Saudi Arabian training sites before helping them return to the battlefield. It's unclear how long they would need to be trained to be battle-ready or how the U.S. could ensure their attention remained on fighting extremists and not just the Syrian government.
Many Republicans and Democrats have expressed reservations about the ability to identify moderates in a country awash with rebel formations and shifting alliances. The Islamic State grew out of the al-Qaida movement, but the two are now fighting. In some instances, the moderate Free Syrian Army has teamed with al-Qaida's local franchise, the Nusra Front.
The House's effort would provide lawmakers with information on the vetting process and which groups were being recruited. The administration didn't ask for money to conduct the arming and training mission because it expects foreign donors to fund the program. In any case, the Pentagon has billions of dollars in wartime contingency funds it can ask Congress to release.
Hagel testifies again before the House panel Thursday. Secretary of State John Kerry appears before separate panels Wednesday and Thursday.