State Department officials on Capitol Hill on Thursday conceded they had not done enough to protect the four Americans who died during a terrorist strike in Benghazi, Libya, and vowed to reform security for U.S. assets overseas.

The Sept. 11 terrorist attack on a U.S. consulate in Libya, where American Ambassador Christopher Stevens died, led to the downfall of President Obama's preferred candidate for secretary of state, Susan Rice, and just this week resulted in the resignation four State Department officials.

"We learned some very hard and painful lessons in Benghazi," Deputy Secretary of State William Burns told the Senate Foreign Relations Committee, outlining various changes in department policy. "We are already acting on them. We have to do better."

But after the congressional hearing Thursday, in which lawmakers reviewed a scathing report that faulted the State Department for a "security posture that was inadequate for Benghazi and grossly inadequate to deal with the attack," some wondered whether Obama, at least politically, had put the event in his rearview mirror.

"What else is there to do?" asked Aaron David Miller, a former Middle East negotiator and adviser to six secretaries of state. "It will hang around a while longer, but then given the focus on an enormous amount of other news, I'm not sure how far this goes."

Republicans have hammered the Obama administration for its handling of the violence, particularly its insistence that the attack was caused by a spontaneous reaction to an anti-Islam video -- an assertion soon proved false.

Outgoing Secretary of State Hillary Clinton, who missed Thursday's hearings for health reasons, is expected to testify next month. Obama has mostly weathered the controversy, and when it was suggested Thursday that the ousted State Department employees had "taken the fall" for senior officials, White House press Secretary Jay Carney became indignant.

"They're not taking the fall," Carney said. "Taking the fall suggests that this isn't accountability and responsibility -- that's what this is. What are you suggesting?"

The incident is a clear blemish for Clinton, who is routinely mentioned as a possible 2016 candidate for president. Obama, who invited lawmakers to "go after me" when criticizing the government response to Benghazi, rarely mentions the incident.

Even some of Obama's detractors doubt further political fallout from the terrorist strike.

"You hate to politicize this kind of event, but I worry that Obama dodged a bullet simply by calling for a review," said Matt Schlapp, former White House political director for President George W. Bush. "I worry that the political consequences aren't what they should be."

Rice, the U.S. ambassador to the United Nations, dropped out of contention for secretary of state largely because of intense Republican focus on her Sunday-show assessment of the Benghazi attacks. Now, Sen. John Kerry, D-Mass., who presided over the Senate hearing Thursday, is expected to replace Clinton.

On Thursday, the White House was looking to move on from the controversy.

"The president accepts the report," Carney said, "and wants every recommendation implemented."