WASHINGTON - So much could have gone wrong as SEAL Team Six swept over Pakistan's dark landscape, dropped down ropes into a compound lined by wall after wall, exchanged gunfire and confronted "Geronimo" face to face. The vital things went right.
Just about every contingency the 25 commandos trained for came at them, rapidly, chaotically and dangerously, in their lunge for Osama bin Laden.
They had acted on the best intelligence the U.S. had ever had on bin Laden's whereabouts since he slipped away in the mountains of Tora Bora just under a decade ago. But it was guesswork, too, with the commandos' lives, a president's reputation and a nation's prestige riding on the outcome.
Was the man once seen pacing the compound's courtyard really bin Laden, as it appeared to American eyes? That was just one unknown.
In short, the U.S. had no direct evidence that bin Laden would be there during the assault or indeed had ever been there. Obama put the raiders in motion on the "pretty good chance" they would find their man, as CIA Director Leon Panetta, who was overseeing the operation back in Washington, put it.
Days after the attack, the administration has fleshed out a reconstruction that is probably more accurate than its initial, flawed telling. More information has been gleaned from the commandos themselves, now back at their home base outside Virginia Beach, Va. Some dust has settled.
But there remains no independent or competing account to the administration's story as yet. The reconstruction comes largely from Panetta, White House spokesman Jay Carney and Obama's counterterrorism adviser, John Brennan. Some of their early details proved unreliable.
The only other direct witnesses are the compound's occupants, now in Pakistani custody and, for now, out of reach to everyone else.
Information gaps exist in the official account. Among them: how many armed defenders the raiders encountered, who shot at whom, why none of the compound's survivors was taken away by the Americans, and how many commandos stormed bin Laden's room. It may never be known which commando, or two, killed bin Laden with shots to his head and chest.
The question of exactly what the unarmed bin Laden did to prompt the SEALs to kill rather than capture him has not been settled. However, officials speaking anonymously told The Associated Press that bin Laden appeared to be lunging for a weapon in a room that contained his trademark AK-47 assault rifle and side arms. Still, to some in government and intelligence circles, the operation bore the hallmarks of a pure kill mission despite statements from officials that bin Laden would have been taken alive if he had surrendered.
On one point, however, there has been no inconsistency, revision or challenge: The raiders of Team Six made good on their "pretty good chance" and got safely away in a bold mission accomplished.
The clandestine SEAL team is back the U.S., CBS News correspondent David Martin reported Wednesday. Meanwhile their commander, Vice Adm. William McRaven provided his account of the violence in closed briefings to congressional committees.
When the SEALs tried to burst through a door at bin Laden's compound, they found a brick wall behind it and had to blast their way through it. On the first floor they found two couriers and a woman, all of whom were killed in a hail of gunfire.
"The SEALs clearly were taking fire throughout the course of the building that they had entered," said Republican House Intelligence Committee chairman Mike Rogers. "There were barricades along the way to prevent them to getting to where bin Laden was."
the SEALs left behind at the compound have surfaced, and they are graphic. They include the courier who unwittingly led U.S. intelligence to the hideout and one of bin Laden's sons.
Late last week, Panetta got the word from the White House that Obama was giving the green light for the raid. Other options, including the idea of "just blowing the place up" from a B-2 bomber, had been discarded, he said. The president's order soon followed.
Obama directed Panetta to proceed under Title 50, meaning this would be a covert operation.
Operational control fell to Adm. William McRaven, head of the Joint Special Operations Command, who is stationed in Afghanistan. Panetta said: "My instructions to Admiral McRaven were, `Admiral, go in and get bin Laden. And if he's not there, get the hell out."'
Team Six was ready.
Its members had rehearsed the assault many times two or three times a night in Afghanistan, Panetta said. The U.S. had a strong sense for at least several months that bin Laden might be at the compound, which Americans had been monitoring for months longer than that.
Intelligence officials watched so closely that they saw a family's clothes on the third floor balcony and, at one point, a man resembling bin Laden out in the courtyard, Panetta said. They surmised bin Laden and his "hidden family" lived on the second and third floors, because his trusted courier who had unwittingly drawn the U.S. to this unlikely hideout occupied the first floor, with his brother in a guesthouse.
When two Black Hawk helicopters carrying the commandos left Bagram Air Base in Afghanistan, stopping in Jalalabad before crossing over into Pakistan on their way to Abbottabad, the operation invited its first risk. Pakistani authorities, kept in the dark about the U.S. mission in their territory, might spot the choppers and engage them.