TERROR AT A SHRINE.

Examines the implications of a car bomb explosion outside a shrine in Najaf, Iraq, which killed Shiite cleric Ayatullah Mohammed Bakir al-Hakim. How this act of violence demonstrates the extraordinary complexity of the challenges facing U.S. troops in Iraq; Details of the blast; Number of dead and injured; Rescue work; Role of U.S. soldiers; Suspects, including al-Qaeda; Reactions of the U.S. George W. Bush administration; The power struggle within the Shiite leadership; Role of Muqtada al-Sadr, head of the radical Shiite organization, the Sadr Group; Denial of al-Sadr of any involvement in the attack; Intensity of the struggle for Shiite supremacy.