Obama spoke as one senior American military official said the Persian Gulf nation of Qatar was expected to start flying air patrols over Libya by this weekend, becoming the first member of the Arab League to participate directly in the military mission. Obama and NATO had insisted from the start on Arab support.
With congressional critics growing more vocal, the president defended the wisdom of the operation so far.
"It is in America's national interests to participate ... because no one has a bigger stake in making sure that there are basic rules of the road that are observed, that there is some semblance of order and justice, particularly in a volatile region that's going through great changes," Obama said.
With longtime autocratic governments under pressure elsewhere in the Arab world, the president made clear his decision to dispatch U.S. planes and ships to intervene in Libya did not automatically signal he would do so everywhere.
"That doesn't mean we can solve every problem in the world," he said.
The president also suggested the administration would not need to request funding from Congress for the air operations but would pay for them out of money already approved.
Administration officials briefed lawmakers during the day about costs and other details to date.
Secretary of State Hillary Rodham Clinton, meanwhile, said the administration is getting reports — of questionable credibility — that some in Gadhafi's inner circle may be looking for a way out of the crisis. She said some of them, allegedly acting on the Libyan leader's behalf, have reached out to people in Europe and elsewhere to ask, in effect, "How do we get out of this?"
"Some of it is theater," Clinton said in an interview with ABC's Diane Sawyer. "Some of it is, you know, kind of, shall we say game playing." She added: "A lot of it is just the way he behaves. It's somewhat unpredictable. But some of it we think is exploring. You know, 'What are my options? Where could I go? What could I do?' And we would encourage that."