Former President Bill Clinton says he warned President George W. Bush before he left office in 2001 that Osama bin Laden was the biggest security threat the United States faced.
Speaking at a luncheon sponsored by the History Channel yesterday, Mr Clinton said he discussed security issues with Mr Bush in his "exit interview," a formal and often candid meeting between a sitting president and the president-elect.
"In his campaign, Bush had said he thought the biggest security issue was Iraq and a national missile defence," Mr Clinton said. "I told him that in my opinion, the biggest security problem was Osama bin Laden."
The US government has blamed bin Laden's al-Qaeda network for the September 11th attacks.
Timemagazine reported last year that a plan for the United States to attack the al-Qaeda network languished for eight months because of the change in presidents and was approved only a week before the September 11th attacks.
But the White House disputed parts of that story, which was published by the magazine in August 2002.
Mr Clinton said his inability to convince Mr Bush of the danger from al-Qaeda was "one of the two or three of the biggest disappointments that I had."
Mr Clinton said that after bin Laden, the next security priority would have been the absence of a Middle East peace agreement, followed by the proliferation of weapons of mass destruction.