Trends in conflict: What do we know and what can we know?

Abstract

Contending arguments on the causes of war often have divergent implications for trends and the possibility for change. Many argue that we observe a decline in conflict and violence, contrary to traditional conceptions of warfare as a fundamentally inescapable problem. Critics challenge whether conflict is in decline, our ability to make inferences about trends from existing data, and to what extent we can learn from the past about the present and the future. We provide a non-technical overview of the contending positions and the concepts necessary to understand the current debate. We review trends in common measures such as the number of conflicts and severity of wars, plausible models for distributions and the timing of conflicts, as well as the role of theory and assessing uncertainty. We conclude with some thoughts on how to advance research on trends in conflict and how to assess change at particular points in history.