Alliance Politics during the Cold War: Aberration,New World Order,or Continuation of History?

Scholars have often wondered whether the nature of alliance politics fundamentally changed during the bipolar nuclear era characterized by the Cold War. The extension of the Alliance Treaty Obligations and Provisions (ATOP) dataset to include the years from 1815 to 2003 allows us the ability to evaluate systematically whether the Cold War period was an aberration, different both from the periods that preceded it and those that followed it, the beginning of a new alliance politics that has continued in the post—Cold War era, or similar in dynamics to eras both before and since. We begin this descriptive project here. While we find some evidence of the distinctness of the Cold War era, what is more notable in the design of alliances is a trend over time away from “reactive alliances” (which are designed to deal with specific crises) and toward “standing alliances” (which are broader and more enduring). In terms of the effects of alliances, we do find evidence that Cold War dynamics are distinct from those of prior eras. In a replication of a well-known study by Russett and Oneal (2001), we reinforce the finding that shared alliance commitments are related to peace during the Cold War, but not in earlier eras. In addition, we demonstrate that the effect of shared alliances on peace depends on the type of alliance commitment.