Obama said he leaned toward the possibility of bringing bin Laden to trial in the U.S. federal court system for masterminding the Sept. 11, 2001, attacks on the United States, journalist Mark Bowden says in "The Finish," to be released Oct. 16.
"Frankly, my belief was if we had captured him, that I would be in a pretty strong position, politically, here, to argue that displaying due process and rule of law would be our best weapon against al-Qaida, in preventing him from appearing as a martyr," Obama is quoted in the book as saying.
He said he and his advisers "worked through the legal and political issues that would have been involved" in bringing him to the United States, including "Congress and the desire to send him to Guantanamo, and to not try him, and Article III."
Article III of the U.S. Constitution establishes the judicial branch of the federal government.
Obama explained that before he made the decision to raid bin Laden's private residential compound in Abbottabad, Pakistan, he wasn't sure a man known as "The Pacer," seen in surveillance videos regularly walking around the Abbottabad compound's vegetable garden, was in fact bin Laden.
He could have been a drug dealer or someone who had a mistress or a second family, Obama said.
Shortly before the go or no-go decision, Obama told his advisers he saw the odds as 50-50 bin Laden was actually living in the compound.
"This is a flip of the coin. You guys, I can't base this decision on the notion that we have any greater certainty than that," Obama said.
In the last moments before the raid was carried out, Obama told Bowden: "It was a matter of taking one last breath and just making sure, asking is there something that I haven't thought of? Is there something that we need to do?
"At that point my estimation was that we weren't going to be able to do it better a month or two months or three months from now," Obama explained. "We weren't going to have better certainty about whether bin Laden was there, and so it was just a matter of pulling the trigger."
Bin Laden was shot and killed May 2, 2011, inside the compound by Navy SEALs of the U.S. Naval Special Warfare Development Group, led by the CIA.
Bowden says the SEALs had no real plans to take bin Laden alive, even though they could have.
Bowden, part of whose book is adapted in the just-published November issue of Vanity Fair magazine, contradicts reports many top presidential advisers opposed the raid, saying the only major dissenters were Vice President Joe Biden, who didn't think the intelligence was strong enough, and Defense Secretary Robert Gates, who later changed his mind.
Before the final decision was made, Leon Panetta, who was CIA director at the time and became defense secretary two months after the raid, told Obama to consider asking himself, "What would the average American say if he knew we had the best chance of getting bin Laden since Tora Bora and we didn't take a shot?"
The battle of Tora Bora was a five-day December 2001 military engagement in a cave complex in eastern Afghanistan's White Mountains, where Washington believed bin Laden was hiding -- but bin Laden avoided capture and fled to Pakistan.