BUSH TO CREATE NEW UNIT IN F.B.I. FOR INTELLIGENCE
Pres Bush creates new national security division within Federal Bureau of Investigation that will fall under overall direction of new national intelligence director John D Negroponte; directive's aim is to break down old walls between foreign and domestic intelligence activities, and to consolidate power of Negroponte, whose authority over FBI has been ambiguous; it will elevate intelligence operations to new prominence within FBI, which has remained firmly oriented toward traditional law enforcement, even since 9/11 attacks; White House leaves it to Negroponte to carry out overhaul; this is among most far-reaching changes yet taken by Bush administration and Congress to overhaul intelligence structure whose deep flaws have been exposed by major failures on terrorism and Iraq; it was among recommendations made by presidential commission headed by Laurence Silberman and Charles Robb; new organization chart (M)