President Obama's inner circle had "voiced doubts" about the plan to raid Usama bin Laden's compound, the president said in an interview, stressing that the few who knew about the mission were not at all certain bin Laden lived there.

Discussing for the first time the many risks involved in the mission, Obama stressed that the operation was a gamble up until the very end.

"At the end of the day, this was still a 55/45 situation. I mean, we could not say definitively that bin Laden was there," the president told CBS' "60 Minutes."

Obama said those on his national security team who questioned the plan provided "invaluable" advice, because their skepticism resulted in a "sharper" mission -- and their concerns reflected his own.

"When I finally did make the decision, I was making it based on the very best information. It wasn't as if any of the folks who were voicing doubts were voicing something that I wasn't already running through in my own head," Obama said.

More On This...

He said the mission looked "promising" from the start. As has been revealed in several briefings and interviews over the past week, U.S. officials began to feel more confident that a high-level Al Qaeda operative like bin Laden was living there the more they found out about the compound in northern Pakistan.

But the president noted that when the ball started rolling on the operation last August, officials had "no direct evidence" that bin Laden was living there.

The president said there would have been "significant consequences" had bin Laden not been there.

"Obviously, we're going into the sovereign territory of another country and landing helicopters and conducting a military operation. And so if it turns out that it's a wealthy, you know, prince from Dubai who's in this compound -- and, you know, we've sent Special Forces in -- we've got problems," Obama said.

But he said his No. 1 concern was whether or not the U.S. team of Navy SEALs could make it out safely. He suggested past military failures that led to loss of U.S. life weighed on him and he worried about the possibility of somebody on the compound setting off explosives, among other hazards.

"I mean, you think about Black Hawk Down. You think about what happened with the Iranian rescue," Obama said. "I am very sympathetic to the situation for other presidents where you make a decision. You're making your best call, your best shot."

Obama said he ultimately made the call to green-light the bin Laden operation because the potential benefit outweighed the risk.

"I said to myself that if we have a good chance of -- not completely defeating but badly disabling Al Qaeda -- then it was worth both the political risks as well as the risks to our men," the president said, noting that he pledged while running for president that if the country ever got a shot at bin Laden, "we're going to take it."

Obama said he was nevertheless nervous as he watched the SEALs team raid the compound via video feed from Washington last week, particularly when one helicopter went down.

"But this is exactly where all the work that had been done anticipating what might go wrong made a huge difference," Obama added. "There was a backup plan."

He also said the national security team, watching from afar, "had a sense of when gunfire and explosions took place." He said the SEALs "had to blow up some walls" presumably to gain access to parts of the compound.

He described those moments of watching and waiting "as the longest 40 minutes of my life with the possible exception of when Sasha got meningitis when she was three months old."

Now that bin Laden is dead and the United States is analyzing a trove of files seized from the compound, Obama said he anticipates the U.S. can pick up leads on other high-value terror targets.

"We're not done yet, but we've got the opportunity, I think, to really, finally defeat at least Al Qaeda in that border region between Pakistan and Afghanistan," Obama said.

Obama also said the thought of actually taking bin Laden down did not weigh on him in the slightest.

"As nervous as I was about this whole process, the one thing I didn't lose sleep over was the possibility of taking bin Laden out," Obama said. "Justice was done. And I think that anyone who would question that the perpetrator of mass murder on American soil didn't deserve what he got needs to have their head examined."