Threats derive their value only from the audience who receives them. [causal]
Angelo’s only interest in torturing the brother is in what he may gain by making a threat to do so; once there is somebody available to whom the threat can profitably be communicated, the possibility of torture has value for Angelo—not the torture itself, but the threatening of it. The sister has gotten negative value out of her trip; having identified her interest and made herself available to receive the threatening message, she has been forced to suffer what she would not have had to suffer if she had never made her identity known or if she could have disappeared into the crowd before the threat was made.
DEFINE: Illuminates how the value of a threat lies in its communication to an identifiable recipient, not in the act it threatens.
Thomas C. Schelling, The Strategy of Conflict, loc. 326