( CNN ) -- Secretary of Defense Leon Panetta says there is no question that the United States is safer with Osama bin Laden , the architect of al Qaeda , dead , but contends there is no `` silver bullet '' to destroy the terror network . Panetta 's assessment came just days before the one-year anniversary of the U.S. commando raid on bin Laden 's compound in Abbottabad , Pakistan , that ended a manhunt for the al Qaeda founder that began following the September 11 , 2001 , terror attacks . `` Having been involved in operations even before bin Laden , it was clear that there is no kind of silver bullet here to suddenly be able to destroy al Qaeda and that includes going after bin Laden , '' Panetta told reporters Friday after a meeting with defense counterparts in South America . `` The way this works is that the more successful we are in taking down those that represent their spiritual and ideological leadership , the greater our ability to weaken their threat to this country . '' The FBI and the Department of Homeland Security last week warned of the possibility of terrorist attacks leading up to and after the anniversary of the May 2 , 2011 , killing of bin Laden . There is no specific , credible terror threat , the agencies said . The warning , released by the FBI and DHS , says individuals have posted messages on `` violent extremist Web forums '' vowing attacks on the United States around the anniversary , but adds that `` such threats are almost certainly aspirational . '' `` I do n't think there 's any question that America is safer as a result of the bin Laden operation , '' Panetta said. '' ... It does n't mean that they do n't remain a threat . It does n't mean that we somehow do n't have the responsibility to keep going after them wherever they are . '' He described the raid that he oversaw as the then-CIA director as `` tense , '' with several `` nerve-wracking moments . '' Panetta recalled the moment during the raid when one of two helicopters used by Navy SEALs crashed at bin Laden 's compound in Abbottabad , Pakistan . `` Just the fact that having those helicopters going 150 miles into Pakistan and the concern about whether or not they would be detected . And then actually going in to the compound when one of the helicopters went down because of the heat coming off the ground . It was just hotter than anybody had anticipated . And obviously that was pretty nerve-wracking , '' he said . `` ... Fortunately , we had a back-up helicopter that came in and was able to pick up the people that were there . '' The biggest question during the operation , Panetta said , was `` whether or not bin Laden was really there . '' `` We had no specific information that he was actually located there . All we had was , you know , just a lot of circumstantial intelligence and information . But all of us were , were kind of holding our breath to find out whether or not he was actually there . '' The answer came about 20 minutes after the SEALs entered the bin Laden compound , with the utterance of the code word `` Geronimo . '' `` There was a huge sigh of relief by everybody involved in that , '' he said . While many details of the raid are known , questions remain about how bin Laden could have been in living for years in a compound that was only a mile from the Pakistan Military Academy in Abbottabad , a largely military community outside the capital , Islamabad . The U.S. raid , which was conducted without the knowledge of Pakistan , enraged the Pakistani public and deploy embarrassed its military . Panetta has said he remains convinced that someone with authority in Pakistan knew bin Laden was hiding at the compound . That claim has been denied by Pakistani officials . U.S.-Pakistani relations remain tense , in part because of U.S. drone strikes inside the country . Pakistan has in essence halted much of its cooperation with the United States while its parliament reassess future terms of engagement with Washington following a U.S. airstrike in November that killed 24 Pakistani soldiers along the border with Afghanistan .
Leon Panetta : There is no doubt the operation to get Osama bin Laden made the U.S. safer . Panetta was the CIA director during the May 2 , 2011 , raid in Abbottabad , Pakistan . He said that it's a " very difficult decision for me personally