US Attorney General Eric Holder has said that the raid on Osama Bin Laden's hideout, in which the al-Qaeda leader was killed, was "not an assassination".
Mr Holder told the BBC the operation was a "kill or capture mission" and that Bin Laden's surrender would have been accepted if offered.
The protection of the Navy Seals who carried out the raid was "uppermost in our minds", he added.
Bin Laden was shot dead on 2 May in his compound in Abbottabad, Pakistan.
Mr Holder said the special forces had acted "in an appropriate way" in the absence of any clear indication Bin Laden had been going to surrender.
"If the possibility had existed, if there was the possibility of a feasible surrender, that would have occurred," he said.
"But their protection, that is the protection of the force that went into that compound, was I think uppermost in our minds."
The attorney general reiterated that the operation was legal, saying that international law allows the targeting of enemy commanders.
"I actually think that the dotting of the i's and the crossing of the t's is what separates the United States, the United Kingdom, our allies, from those who we are fighting," he said.
"We do respect the rule of law, there are appropriate ways in which we conduct ourselves and expect our people to conduct themselves, and I think those Navy Seals conducted themselves in a way that's consistent with American, [and] British values."
Mr Holder said that material seized from Bin Laden's home, stored on around 100 flash drives and five computers, had revealed that the al-Qaeda leader was still closely involved in the running of the organisation.
"From what we have seen in just this initial review of the material shows that he was surprisingly in command of al-Qaeda," Mr Holder said.
"He was operationally involved in the work of al-Qaeda, it was not something that I think we expected necessarily to see. The information we have... showed that he was pushing al-Qaeda to engage in more plots in more areas of the world and on specific dates."
Mr Holder said that despite the death of Bin Laden, al-Qaeda still posed a threat to the US and its allies.
"I think this has been a significant step," he said. "One cannot understate the importance of eliminating Bin Laden. He was a symbolic head of the organisation and, as we now know, an operational head of the organisation.
"But the threat has not gone. We have to face others in al-Qaeda, others still sworn to do harm to the US and its allies... and in the US over the past 18 months or so we have seen a new brand of terrorism, these home-grown radicals... who come after the American people. We have to deal with them as well."
The interview with Mr Holder comes a day after a statement by Bin Laden's family questioning why he was not captured alive.
His sons criticised the US for carrying out his "arbitrary killing".
The UN has also raised concerns. Special rapporteurs Christof Heyns and Martin Scheinin said deadly force was permissible in exceptional cases as a last resort.
The raid has had a mixed reaction in Pakistan, and on Thursday several hundred supporters of former Prime Minister Nawaz Sharif rallied in Abbottabad shouting anti-US slogans.
Mr Sharif has called for a full judicial inquiry into the raid.
Meanwhile, members of US Congress are being shown photos of Bin Laden just after his death, which the US government has so far refused to publish.
Oklahoma Senator James Inhofe, who saw them on Tuesday, described them as "pretty gruesome".
In the latest of a series of media briefings, unnamed US security and and intelligence officials said documents seized from the Abbottabad compound showed that Bin Laden had calculated how many Americans would have to die before the US withdrew from the Middle East.
He also encouraged his followers to attack cities such as Los Angeles, as well as New York.