O'Hanlon said, "He's had a pretty nice message on the budget and he's managed the politics of this reasonably well. There hasn't been any big insurrection from the joint chiefs or other corridors that would have been expected.
"We don't know if sequestration is going to happen and we don't know if there will be any further budget cuts. It's an optimistic budget right now, and somebody else is likely going to have to go back for a second round for changes in forces and weaponry."
Shortly after he became Defense secretary, Panetta and Admiral Mike Mullen, the then-chairman of the Joint Chiefs of Staff, certified that the military was prepared to end the two-decade old "don't ask, don't tell," a law that prevented homosexual service members from serving openly in the military.
"This is a historic day for the Pentagon and the nation," Panetta told reporters on the day of DADT's repeal in September, 2011. "As secretary of Defense, I'm committed to removing all barriers that would prevent Americans from serving their country and from rising to the highest level of responsibility that their talents and capabilities warrant.
"These are men and women that put their lives on the line in defense of this country; that's what should matter most."
When Panetta was first selected for the post at the CIA in 2009, some expressed skepticism about how he would perform because he lacked little to no intelligence or national security experience. But Panetta's handling of the CIA and Pentagon eased the worries of many skeptics.
The highlight of his leadership atop the CIA was the operation that led to the death of Osama Bin Laden.
"People learned: never underestimate Panetta," O'Hanlon said. "The Pentagon, if anything, seemed a little bit more conducive to him, more of a management problem. ... I think, overall, he's been pretty solid."
Cordesman said, "In a partisan Washington, survival is to exceed expectation.
"I think that what really counts here is not whether he exceeded expectations. What I think it is that he did well. He did well and did well over a very difficult time."