Deterrence is etymologically and conceptually bound to terror.

Evidence

At the extreme, as John Coetzee muses in his latest novel, deterrence too is conceptually tied to terror, to frightening or terrifying (terrere) opponents (if not also critics) into compliance. Fighting terror with terror. — David Theo Goldberg, The Threat of Race, 271

Categorization

• DEFINE: Etymology of ‘deterrence’ from ‘terrere’ (to frighten) — a conceptual clarification that collapses the supposed distinction between deterrence and terror.
• CANDY: A tidy etymological gotcha: ‘deterrence’ literally shares its root with ‘terror.’
• SEED: Possible essay hook: unpicking the rhetorical separation between ‘deterrence’ and ‘terror’ when they share a root — how language launders state violence.