Published: Mar 30, 2011 6:40 PM EDT
Updated: Mar 30, 2011 3:40 PM EDT

WASHINGTON- The top NATO commander said Wednesday the U.S. military role in Libya will be reduced "measurably" as other nations take on added responsibilities in the war, an assessment that failed to satisfy lawmakers seeking more clarity about President Barack Obama's deployment of American forces.

Testifying before Congress for the second straight day, Navy Adm. James Stavridis said the ratio of air strikes and warplane flights has been about 50 percent U.S. and 50 percent of U.S. partners, but over the next couple of weeks the United States will shift to an "enabler" in the operation.

Stavridis said that of the 40 admirals and senior officers involved, only five are Americans. He said an Italian admiral is overseeing the arms embargo against Libya. He also insisted that the United State would not send ground troops to Libya.

Still, members of the House Armed Services Committee expressed serious reservations about the future U.S. role in Libya, especially if there is a stalemate with Col. Moammar Gadhafi clinging to power.

They planned to pepper Defense Secretary Robert Gates, Secretary of State Hillary Rodham Clinton and Joint Chiefs of Staff Chairman Adm. Mike Mullen with questions at closed-door, back-to-back briefings later in the day on Wednesday.

"It is a mission that I'm concerned as to whether or not its goals are clear. And also I'm a little concerned and believe it's unclear as to who we are supporting in this conflict," said Rep. Michael Turner, R-Ohio.

Said freshman Rep. Chris Gibson, R-N.Y., who did four Army combat tours in Iraq: "I'm opposed to action in Libya. We have so much on our plate to bring to closure."

Obama is under pressure from Congress to spell out an exit strategy for the U.S. military in Libya and provide a clear plan to end Gadhafi's 42-year rule, as the American public remains fiercely divided over the war.

Obama delivered a full-throated defense of his decision to deploy military forces to prevent a slaughter of Libyan civilians in his speech Monday and in the shadow of the United Nations on Tuesday. The president said the nation's conscience and its common interests "compel us to act" to protect civilian lives in Libya.

"We've learned from bitter experience - from the wars that were not prevented, the innocent lives that were not saved - is that all that's necessary for evil to triumph is that good people and responsible nations stand by and do nothing," the president said at the dedication of the Ronald H. Brown mission at the U.N.

In a series of network interviews, Obama insisted that the "noose is tightening" around Gadhafi although forces loyal to the longtime leader pounded the rebels with tanks and rockets Wednesday, forcing them to retreat. The president did not rule out arming the rebels, saying the U.S. and its partners could get weapons into Libya and all options were being considered.

In the course of his statements, however, Obama created more questions among lawmakers when he said ousting Gadhafi militarily would be a mistake and a diplomatic approach would be a better option.

"We hope Gadhafi leaves. I just don't think that that is a strategy," House Speaker John Boehner, R-Ohio, said Tuesday. "When you listen to what's going on and all the words, it is really nothing more than hope. So if Gadhafi doesn't leave, how long will NATO be there to enforce the no-fly zone?"

A new Associated Press-GfK poll found the country split on U.S. involvement in military actions in Libya, with 48 percent approving and 50 percent disapproving.

About three-quarters say it's somewhat likely that U.S. forces will be involved in Libya for the long term. Fifty-five percent say they would favor the United States increasing its military action to remove Gadhafi from power, although only 13 percent favor U.S. ground troops, a step Obama has said he would not take.

The poll was conducted in the days leading up to the president's speech.

Reflecting the nation's divisions, several lawmakers praised Obama's actions while others raised a series of looming questions about the U.S. mission.

Republican Sen. John McCain of Arizona, Obama's 2008 rival for the presidency, said he appreciated the president's explanation of "why this intervention was both right and necessary, especially in light of the unprecedented democratic awakening that is now sweeping the broader Middle East."

McCain said Obama deserves strong bipartisan support in Congress and in the country on Libya.

But Rep. Howard "Buck" McKeon, R-Calif., chairman of the House Armed Services Committee, said Obama needs to further refine U.S. purposes.

"I still did not hear a clearly defined goal for how long military operations will last in Libya," McKeon said. "Utilizing U.S. warriors to protect civilians from a brutal dictator is a noble cause, but asking them to maintain a stalemate while we hold out hope that Gadhafi will voluntarily leave his country raises serious questions about the duration of the mission."

Democratic Rep. Dennis Kucinich of Ohio sought congressional support Tuesday for his effort to cut off funds for the operation.

Under questioning by Congress, NATO's top commander, U.S. Navy Adm. James Stavridis, said officials had seen "flickers" of possible al-Qaida and Hezbollah involvement with the rebel forces. But Stavridis said there was no evidence of significant numbers within the political opposition group's leadership.

"The intelligence that I'm receiving at this point makes me feel that the leadership that I'm seeing are responsible men and women who are struggling against Colonel Gadhafi," Stavridis told a Senate panel. "We have seen flickers in the intelligence of potential al-Qaida, Hezbollah. ... At this point, I don't have detail sufficient to say that there's a significant al-Qaida presence or any other terrorist presence in and among these folks."

Obama, in an interview with CBS News, said most of the opposition leaders are professionals such as lawyers and doctors, but "that doesn't mean that all the people - among all the people who opposed Gadhafi - there might not be elements that are unfriendly to the United States and our interests."

Clinton met in London with Mahmoud Jibril, a representative of the Libyan political opposition. The Obama administration is not ruling out a political solution in Libya that could include Gadhafi leaving the country, she said, but she acknowledged there is no timeline.

Meanwhile, the Pentagon put the price tag for the war thus far at $550 million.

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