Despite the recent release of taped messages in which bin Laden suggests that more attacks on American interests are being plotted, Bush said he believes the al Qaeda leader "is not as strong as he was."
"He's going to be weaker, and I intend to use our resources to bring him to justice," the president said. "We will stay on the hunt."
The president also told Walters he has no regrets about his administration's decision to wage war in Iraq, despite inspectors' failure to find any weapons of mass destruction in the country -- the chief rationale for the March 2003 invasion and toppling of Saddam Hussein's regime.
The White House acknowledged Wednesday that there is no longer an active search for Iraqi weapons of mass destruction. The final report from chief U.S. weapons inspector Charles Duelfer, due out next month, has concluded that "the former regime had no formal written strategy or plan for the revival of WMD."
The Bush administration does not hold out hopes that any weapons will ever be found.
"I felt like we'd find weapons of mass destruction -- like many here in the United States, many around the world. The United Nations thought he had weapons of mass destruction," Bush told Walters. "So, therefore: one, we need to find out what went wrong in the intelligence gathering. ... Saddam was dangerous and the world is safer without him in power."
Despite the deaths of more than 1,300 U.S. military personnel and the multibillion-dollar price tag, the ouster of Saddam justified the invasion, he said.
"The removal of Saddam Hussein has made America safer because a dictator, a tyrant, a thug, with whom we had been at war in the past, who was destabilizing a vital part of the world, who was paying the families of suicide bombers, is no longer in power," Bush said. "And he no longer has the capacity to reconstitute a weapons program. ... Yes, it's worth it."