Strategic Communication Protocols provide a structured approach for first contact with interstellar objects that demonstrate technological characteristics and high levels of threat. The protocols find their starting point in an ISO Information-Communication Paradox, namely, as our knowledge of an ISO's threatening capabilities increases, the probability of successful communication decreases while the urgency of communication attempts simultaneously intensifies. From this paradox, a Threat-Communication Viability Index is created to describe when the value of communication attempts outweighs strategic silence. The index scores the situation and operates as a decision-making tool for stakeholders tracking an ISO. The communication protocols subsequently outline several diplomatic strategies in cases where the index recommends communication.