"For nearly a century, in short, offshore balancing prevented the emergence of dangerous regional hegemons and pre­served a global balance of power that enhanced American security. Tellingly, when U.S. policymakers deviated from that strategy—as they did in Vietnam, where the United States had no vital interests—the result was a costly failure."

Theory creating and hypothesis testing are both critical components of social science, but the former is ultimately more important. Yet, in recent years, International Relations scholars have devoted less effort to creating and refining theories or using theory to guide empirical research. Instead, they increasingly focus on 'simplistic hypothesis testing,' which emphasizes discovering well-verified empirical regularities. Privileging simplistic hypothesis testing is a mistake, however, because insufficient attention to theory leads to misspecified empirical models or misleading measures of key concepts.