SAN PEDRO SULA, Honduras - Bishop Romulo Emiliani was angry, his tattooed flock shamefaced and silent. "Why," he demanded, "must you kill your brothers?" The bishop was near tears, but still no one answered. Four days earlier, Emiliani was in this same prison courtyard, singing and praying and asking God's forgiveness with the same 100 or so members of Mara Salvatrucha, a street gang formed by criminal deportees from Los Angeles. But now, during Easter week, they had killed again. This time, they didn't disembowel their victims. This time, all seven were found dead in their bunks. A needle and...