Ahead of the anniversary of Osama bin Laden's death, a top American counter-terrorism official said that the core of bin Laden's terror organization, al Qaeda, is in shambles and is a "shadow of its former self," but the fight continues.

"We've always been clear that the end of bin Laden would neither ark the end of al Qaeda, nor our resolve to destroy it," White House counter-terrorism advisor John Brennan said today. "When we assess the al Qaeda of 2012, I think it is fair to say that, as a result of our efforts, the United States is more secure and the American people are safer."

Brennan, speaking at the Woodrow Wilson International Center for Scholars, said that documents recovered from the Navy SEAL raid that killed bin Laden - to be published online later this week - showed the terror leader was disheartened by "disaster after disaster" and was deeply concerned after several of al Qaeda's top leaders were killed or captured.

"With its most skilled and experienced commanders being lost so quickly, al Qaeda has had trouble replacing them," Brennan said. "In short, al Qaeda is losing badly. And bin Laden knew it."

"Today, it is increasingly clear that - compared to 9/11 - the core al Qaeda leadership is a shadow of its former self," he said. "For the first time since this fight began, we can look ahead and envision a world in which the al Qaeda core is simply no longer relevant," he said.

However, Brennan said that though the core of al Qaeda has been weakened, the threat has not disappeared - the fight has just expanded to al Qaeda's affiliates.

"Despite the great progress we've made against al Qaeda, it would be a mistake to believe this threat has passed," he said. "Al Qaeda and its associated forces still have the intent to attack the United States."

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