Here again is a threat that all-out war may occur, not that it certainly will occur, if the other party engages in certain actions. Again, whether it does or does not occur is not a matter altogether controlled by the threatener. Just how all-out war would occur—just where the fault, initiative, or misunderstanding may occur—is not sure. Whatever it is that makes limited war between great powers a risky thing, the risk is a genuine one that neither side can altogether dispel if it wants to. The final decision, or the critical action that initiates an irreversible process, is not something that should necessarily be expected to be taken altogether deliberately. "Chance" helps to decide whether general war occurs or not, with odds that are a matter of judgment based on the nature of the limited war and the context in which it occurs.

DEFINE: Clarifies the concept of 'threat' as a conditional (war may occur if) rather than a certainty, and distinguishes deliberate decision from chance-driven escalation.

Thomas C. Schelling, The Strategy of Conflict, loc. 425