Though usually assumed by scholars of international relations to have been one-of-a-kind, the Cold War—the global East-West rivalry that ended with the peaceful dissolution of the Soviet Union—resembled in many of its features an earlier match usually assumed by scholars of American history to have been entirely exceptional: the continental North-South rivalry that ended with the War Between the States. Each was a contest of ideologically ambitious, institutionally immiscible, and territorially extensionist socioeconomic systems. Each rivalry evolved a mechanism for the procrastination of conflict. In both cases this mechanism was initially deliberative—based on debate. It remained deliberative in the North-South case, which deteriorated from cooperation to catastrophe, but it switched from deliberative to confrontational—based on threat—in the East-West case, which ended in voluntary unilateral abandonment of ideology, institutions, and territory. The irony of the outcomes of these two rivalries, whose likelihoods of violent end would probably have been misranked at their respective midpoints, is discussed.