WASHINGTON (CN) - With momentum building in the fight against Islamic State militants, Defense Secretary Ash Carter told the Senate Armed Services Committee on Wednesday that the United States and "will not hesitate to expand" assistance to local Sunni Arab forces.
Cautioning against "Americanizing" the conflict with the addition of more U.S. ground forces, Carter reiterated his support for training, advising and assisting local ground forces as the key to defeating the Islamic State in Iraq and the Levant.
"U.S. and international coalition forces can and will do more to enable them, but we cannot substitute for them," Carter said.
Such an undertaking would largely fall on U.S. shoulders, would likely inspire new anti-U.S. threats, he added, saying the securitization and governing of territory is a task for local forces.
Gen. Paul J. Selva, vice chairman of the Joint Chiefs of Staff, echoed that sentiment and said the U.S. should not get baited into a ground war against ISIL.
In a quiet moment at the end of the three-hour hearing on anti-ISIL strategy, Selva told a handful of remaining senators that working with willing Sunni-Arab partners will have the intended effect if the U.S. stays the course.
Calling ISIL "barbaric," Selva said there needs to be more focus on who ISIL is and what they do. ISIL is "not creating a caliphate that's consistent with Islamic teaching," he said. "They're creating a caliphate that's consistent with their narrative of Western subjugation and extremist Islam," he added.
"If we fall into the trap of radical Islamic violent extremists baiting us into a ground fight, we're actually doing exactly what they want us to do," Selva concluded.
The hearing came just days after the apparently ISIL-inspired shooting in San Bernardino, Calif., that killed 14 people and injured 21.
Meanwhile in a hearing of the Senate Judiciary Committee this morning, FBI Director James Comey said investigators are looking into whether the Islamic State had arranged the marriage of the couple behind those Dec. 2 attacks.
At the Armed Services Committee hearing, calls for swift and clearly defined action reverberated in the room, with some senators chiding the witnesses for an alleged lack of strategy in defeating ISIL.
Sen. Lindsey Graham, a Republican from South Carolina, presented an authorization of use for military force that would place no limits on sending U.S. ground forces to engage ISIL.
Graham said a stronger response is needed to send a clear message to the organization: "We're after you wherever you go, as long as it takes, whatever is required to defeat you."
Carter said there are 3,500 U.S. troops now in noncombatant roles assisting Iraqi Security Forces at six locations in Iraq, where the U.S. has provided increased lethal fire capability, and more specialized training and equipment.
The Defense Department will provide attack helicopters and accompanying advisers if the circumstances dictate it, and if Iraqi Prime Minister Haider al-Abaddi requests it, Carter added.
The U.S. is also "deploying a specialized expeditionary targeting force" to help the Iraqi Security Forces and the Kurdish Peshmerga forces with "a variety of raids and intelligence gathering," Carter said.
As the Defense Department envisions it, this force will conduct a variety of missions focused on interdicting key ISIL figures on the move, Carter said.
The October raid that freed 69 ISIL hostages is one example of what this force can do, the defense secretary added.
Pointing to other evidence that the Obama administration's anti-ISIL campaign is building momentum, Carter said local Syrian and Iraqi ground forces have retaken key territory - with U.S. support - most recently by pushing ISIL out of Sinjar in northern Iraq.
This severed the main communication line between Raqqa, ISIL's proclaimed capital in Syria, and the city of Mosul in Iraq, the two largest cities under ISIL control.
Although ISIL apparently found an alternate route days later, Carter told the Senate committee that "ISIL now must rely on back roads, where we will locate and destroy them."
Syrian local forces have also pushed ISIL out of al Hawl and surrounding territory, Carter said, adding that the train-and-equip program is working better now since the Defense Department made adjustments to it.
The program came under heavy fire in September after Gen. Lloyd Austin, the head of Central Command, told Congress that the program had produced only a handful of capable fighters.
Carter said the U.S. now trains and equips groups that already exist, rather than trying to create brand-new fighting forces.
Under the new approach, the U.S. vets the leaders of existing groups through public and classified databases to check their previous associations and prior conduct, Selva said.
The general counted 20 leaders with the Syrian-Arab coalition, which he said has brought 1,600 fighters to the battlefield and worked through three villages in eastern Syria.
There is no direct command and control, Selva added. Instead, "we exercise influence" by giving them ammunition and advice on how to hit specific targets, along with air support.
Speaking to improvements in the intelligence picture, meanwhile, Carter shot down accusations that the campaign has faltered because of restrictive rules of engagement, which he says have not changed over time.
Selva agreed, basing his agreement on consultations with commanders from the Joint Task Force to Central Command.
"I know of no rules of engagement restrictions that have prevented us from striking targets and that prevented our forces from being as effective as they can be on the ground," Selva said.
Carter said the biggest obstacles thus far have been weather and poor intelligence.
Improved intelligence has enabled more productive air strikes, and allowed for the targeting of oil tankers in November that were transporting ISIL-controlled oil, one of its main sources of revenue.
Selva and Carter both said the U.S. has made efforts not to target general infrastructure that is necessary for daily life in Iraq and Syria, and to avoid civilian casualties that could turn local populations against our anti-ISIL efforts.
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