"No," Panetta responded. "Because the attack ended."

Orders without action

But orders to prepare had been given, the defense secretary testified.

Panetta said a Marine security team platoon stationed in Spain was ordered to prepare for deployment while another platoon prepped to head to the embassy in Tripoli. A Special Operations force, then training in Central Europe, was told to prepare to deploy to a staging base in Southern Europe, and another Special Ops force, based in the United States, was told to prepare to move there, too.

"Some have asked why other types of armed aircraft were not dispatched to Benghazi," he said. Armed drones, AC-130 gunships or fixed-wing fighters with the associated tanking, armaments, targeting and support capabilities were not near Libya, and it would have taken at least nine hours to deploy, he said.

"This was, pure and simple, in the absence, as I said -- of any kind of advance warning -- a problem of distance and time," Panetta said.

The quickest response option available was a Tripoli-based security team, he said.

Within hours, Panetta said, that six-person team, including two U.S. military personnel, chartered a plane and flew to Benghazi.

Within 15 minutes of arriving at the annex facility, they came under attack by mortar and rocket-propelled grenades, he said.

Members of the team and others at the annex facility provided emergency medical assistance and supported the evacuation of all personnel.

All remaining U.S. government employees were evacuated from Benghazi, Panetta said.

Beefing up security

There will "always be tension" between how much security is adequate and how much would create a "bunker-like mentality" at global posts, Panetta said. The answer is not to assign the military to run a "fire house" next to every U.S. diplomatic location.

Panetta noted that Congress, too, plays a role in the security of the nation's diplomatic missions, and that the Department of Defense faces the prospect of sequestration -- which would result in billions of dollars of cutbacks to the Defense budget -- on March 1. "If Congress fails to act, sequestration is triggered," he said.

Panetta also said there must be some reliance on host countries to help with security. The attack in Benghazi "raises concerns" about whether that's always possible. Libya's government has been on shaky ground since Libyan leader Moammar Gadhafi was ousted in 2011.

The defense secretary's testimony comes a few weeks after Clinton told lawmakers that the State Department was moving fast to beef up security at U.S. posts worldwide.

During her testimony, Clinton teared up as she recounted meeting the arrival of the caskets containing the bodies of Stevens and former Navy SEAL commandos Tyrone Woods and Glen Doherty, both of whom had been working as diplomatic security officers. Sean Smith, the fourth American killed, was an information management officer.

Panetta said an FBI team that includes CIA and DOD members "has made very good progress" in identifying the attackers.