This paper is the first of a series of two that present an effort to systematize the application of psychoanalytic theory of group processes to the outbreak of massive violence. It explores the origins and social amplification of primitive aggression by means of group psychology and mass psychology, and the combined influences of the regressive pull of ideologies, the personality features of social and political leadership, and the triggering impact of historical trauma and social crises. The paper describes a spectrum of narcissistic-paranoid mechanisms that provide a common matrix for the analysis of those aspects of social psychology that co-determine socially sanctioned violence.