Cycles of war: Historical speculations on future international violence

The paper offers a historical approach to the problem of future international violence. It begins by arguing that the past can be used to predict the future. The modern European state system (since the fifteenth century) is designated both as an appropriate model and as the background to the present global state system. The history of the European state system reveals periods of war which are designated as probing (low level violence), adjusting (middle level violence) and hegemonic (high level violence); these periods appear to recur in cycles. The paper offers a number of explanations for these cycles and suggests that violence may be functional in the state system as a means of accomodating changes in power. The duration of these cycles may be interpreted as the time required for such power changes to occur. War would appear necessary in a state system which combines moderate change with moderate stability; it might be avoided only if the system were to move to the extremes of non‐change or continual change, the first risking stagnation, the second chaos. A projection of these cycles into the future implies that the last quarter of the twentieth century will be characterized by adjusting wars, followed by a generation of probing wars, then a generation of hegemonic wars, etc. Although mixed and difficult to evaluate, some signs may confirm this prediction. Thus the historical record may indicate that international violence is likely to increase in the last quarter of the twentieth century.