Where does history end and international-relations theory begin?
Short answerThere is no sharp boundary: IR theory looks forward, but it is built from how we understand past behavior.
NotesEvents become history as soon as they have happened. International-relations theory looks toward future relations, but its expectations rest on an understanding of what people have done in the past. The joke that history ends tonight and theory begins tomorrow expresses that change of direction. Because reasoning about the future draws on historical understanding, the two have no sharp boundary.