Political and economic pressures will eventually drive Libyan leader Moammar Gadhafi from power, but the military operation will help force him to make those choices by degrading his defense capabilities, Defense Secretary Robert Gates said Thursday.
As the U.S. turned over control of the military operation to NATO, Gates and Joint Chiefs Chairman Mike Mullen told Congress that the U.S. participation will be limited and will not involve an active role in airstrikes as time goes on.
His comments come as Gadhafi's forces struck forcefully back at the rebels this week, recapturing lost ground and triggering pleas for help from the battered and failing opposition forces.
Gates and Mullen were testifying before the House and Senate Armed Services Committees in the wake of new revelations that small teams of CIA operatives are working in Libya.
Lawmakers uneasy with the parameters of the U.S. commitment in Libya pressed Gates and Mullen about how long the operation will go on and what can be done if there is a stalemate and Gadhafi holds on to power.
Gates declined to comment on the CIA activities in Libya.
U.S. officials have acknowledged that the CIA has sent small teams of operatives into Libya and helped rescue a crew member of a U.S. fighter jet that crashed.
The CIA's precise role in Libya is not clear. Intelligence experts said the CIA would have sent officials to make contact with the opposition and assess the strength and needs of the rebel forces in the event President Barack Obama decided to arm them.
Meanwhile, battlefield setbacks are hardening the U.S. view that the poorly equipped opposition probably is incapable of prevailing without decisive Western intervention, a senior U.S. intelligence official told The Associated Press.
The administration says there has been no decision yet about whether to arm the opposition groups, and acknowledged that the U.S. needs to know more about who the rebels are and what role terrorists may be playing there.
Rep. Adam Smith of Washington state, the top Democrat on the House Armed Services Committee, said the U.S. must better explain to the American public that this is not an open-ended conflict and that the U.S. will not become embroiled in a civil war.
Committee chairman Rep. Howard "Buck" McKeon, R-Calif., said he has concerns about U.S. objectives in Libya.
"History has demonstrated that an entrenched enemy like the Libyan regime can be resilient to airpower," McKeon said.