We have tried to suggest in the preceding chapter that the analysis of rivalry in world politics possesses some considerable potential for revolutionizing the study of conflict. Rather than assume that all actors are equally likely to engage in conflictual relations, a focus on rivalries permits analysts to focus on the relatively small handful of actors who, demonstrably, are the ones most likely to generate conflict vastly disproportionate to their numbers. For instance, strategic rivals, a conceptualization that will be developed further in this chapter, have opposed each other in 58 (77.3 percent) of 75 wars since 1816. If we restrict our attention to the twentieth century, strategic rivals opposed one another in 41 (87.2 percent) of 47 wars. A focus on the post-1945 era yields an opposing rival ratio of 21 (91.3 percent) of 23 wars. Moreover, their conflicts are not independent across time – another frequent and major assumption in conflict studies. They are part of a historical process in which a pair of states create and sustain a relationship of atypical hostility for some period of time. What they do to each other in the present is conditioned by what they have done to each other in the past. What they do in the present is also conditioned by calculations about future ramifications of current choices.