Terrorism is defined by its extranormality and symbolic targeting rather than casualties

Evidence

Defining the concept of terrorism has proved difficult, in part because judgments about what terrorism is frequently depend on the circumstances in which violence occurs. Most writers on this subject rely on one of the earliest definitions, that of Thornton (1964, p. 73), who proposed: “In an internal war situation, terror is a symbolic act designed to influence political behavior by extranormal means, entailing the use or threat of violence.” The violence of terrorism is distinguished from other types of political violence by its extranormality (terrorism exceeds the bounds of socially acceptable violence) and by its symbolic nature (the targets of terrorism are symbols of the state or of social norms and structure) (see Thornton, 1964, pp. 73–78). Terrorism is based on systematic and purposive violence, designed to influence the political choices of other actors more than to inflict casualties or material destruction. To achieve political influence, terrorism depends on its power to arouse emotions in audiences, including the neutral, the supportive, and the antagonistic. — John T. Jost and Jim Sidanius, Political Psychology, 4070

Categorization

• DEFINE: Thornton’s 1964 definition — terrorism as symbolic, extranormal violence aimed at influencing political behavior — is the field’s canonical starting point.
• XREF: Connects to the reader’s broader interest in how categories (like sacrifice, quiet, immodesty) get defined in relation to what society deems normal. — connects to: Terror is a strategy of asymmetric violence deployable by weak or strong actors — Charles Tilly, Regimes and Repertoires, 828