Threats and extortion require deliberate destination-targeted communication structures. [causal]
Many interesting game tactics and game situations depend on the structure of communication, particularly asymmetries in communication and unilateral options to initiate communication or to destroy it. Threats are no good if they cannot be communicated to the persons for whom they are intended; extortion requires a means of conveying the alternatives to the intended victim.
Thomas C. Schelling, The Strategy of Conflict, loc. 338