Sarah Kreps has made a superb contribution to the burgeoning academic literature on the causes of military intervention. This literature reflects the enormity of the task social scientists face in comprehending world affairs.
This enormity stems from the many choices social scientists have to make in order to investigate reality. Unlike physicists, they do not start with a single universe inhabited by objects that obey physical laws and have no independent ideas or social institutions of their own. They confront a universe in which objects have minds of their own, behave interactively through various social networks and institutions, and may or may not act in line with material forces. On top of all that, social scientists inhabit the universe they examine. They are studying themselves. They belong to specific countries and favor certain ideas and institutions. Should they focus on the United States or on other countries? Should they privilege the causal power of ideas, power or institutions? Should they look at the world from an individual, country, or systemic level of analysis?