The former intelligence officer who says that a Defense Department program identified Mohamed Atta and three other hijackers before the Sept. 11, 2001, attacks said yesterday that many of his allegations are not based on his memory but on the recollections of others. Lt. Col. Anthony Shaffer, who has been on paid administrative leave from the Defense Intelligence Agency since his security clearance was suspended in March 2004, said in a telephone interview that a Navy officer and a civilian official affiliated with the Able Danger program told him after the attacks that Atta and other hijackers had been included...