Initial operations in Libya have been very effective, with French, British and U.S. air strikes crippling Libyan dictator Moammar Gadhafi's capabilities, the U.S. military's top-ranking officer said today.

Speaking on CNN's "State of the Union," Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, said that after one day of operations, the coalition already has taken out most of Gadhafi's air defenses and airfields, and that the no-fly zone in Libya has been established.

"We've worked hard to plan this in a relatively short period of time," Mullen said. "I would say that the no-fly zone is effectively in place."

Gadhafi's forces are stretched thin between the Libyan oil towns and major cities of Tripoli and Benghazi, Mullen said, noting that U.S. fighter jets have delivered major blows to forces in those towns and now are working to attack Gadhafi's supply lines.

"We've got combat air patrols and aircraft over Benghazi, and we'll have them there on a 24/7 basis," the admiral explained. "[Gadhafi's forces haven't] flown any aircraft in the past two days. He's pretty well stretched now, and we will endeavor to sever his logistics support here in the next day or so.

"We're in a situation now where what we do will depend to some degree on what he does," Mullen added. "We've focused mainly on his air defense capabilities and airfields, [but] this will allow us to get other capabilities where we can jam his communications and those kinds of things."

Army Gen. Carter F. Ham, commander of U.S. Africa Command, is leading the coalition effort in Libya. Mullen said he expects Ham to hand command off to a coalition commander in the next few days, and that the United States will transition to more of a supporting role in an effort that will involve more nations, including Arab militaries.

"As more and more capabilities from other countries start to show up, I think you'll see the U.S. move to more of a support role," the chairman said. "I'm very confident that there will be military capabilities from some Arab nations, that they are actually moving into theater now.

"That's been the commitment on part of the political leadership in some Arab countries, and I expect that to happen militarily, as well," he added.

Mullen also fielded questions on ABC's "This Week with Christiane Amanpour."
With Arab states joining the coalition effort, Gadhafi is more isolated by the international community than ever before, Mullen said, noting United Nations sanctions and an arms embargo now emplaced on Libya.

Although Gadhafi may be vulnerable, Mullen said, he stressed that the U.S. military objective is not to topple the regime. Rather, he said, it's to ensure the no-fly zone, protect Libyan civilians and support humanitarian assistance to flow into the country.

"We're very focused on the limited objective [President Barack Obama] and the international community has given us in terms of providing the no-fly zone so [Gadhafi] cannot attack his own people, to avoid any kind of humanitarian massacre and to provide for the humanitarian support of the Libyan people," he explained.

The international military effort so far has been very successful, he said.

"From a military standpoint, certainly [Gadhafi's forces] have some capabilities, but they've not been very effective," Mullen said. "He still has, from what I see this morning, some surface-to-air capabilities where he could attack an aircraft, [but] we haven't seen large scales of that after yesterday.

"He clearly still has the capability to attack his own people," the chairman continued. "We're very focused on that, and trying to ensure his military forces don't do that."