Like professional revolutionaries, social scientists seldom clearly understand quite what they are doing. But, again like professional revolutionaries, they do sometimes attain a relatively clear grasp of the implications of what they have already done; and sometimes at least, this constitutes a marked improvement on the achievements of their immediate predecessors.
— John Dunn
In this book I examine the international impact of revolutionary change, focusing primarily on the relationship between revolution and war. My chief objective is to explain why revolutions increase the intensity of security competition between states and thereby create a high probability of war. Because war does not occur in every case, my second objective is to clarify why certain revolutions lead to all-out war while others stop at the brink.
Although major revolutions are relatively rare, this subject is worth studying for at least two reasons. First, revolutions are more than just critical events in the history of individual nations; they are usually watershed events in international politics. Revolutions cause sudden shifts in the balance of power, alter the pattern of international alignments, cast doubt on existing agreements and diplomatic norms, and provide inviting opportunities for other states to improve their positions. They also demonstrate that novel ways of organizing social and political life are possible and often inspire sympathizers in other countries. Thus, although revolutions by definition occur within a single country, their impact is rarely confined to one state alone. 1
Indeed, revolutions usually disrupt the international system in important ways. According to one quantitative study, for example, states that undergo a "revolutionary" regime change are nearly twice as likely to be involved in war as are states that emerge from an "evolutionary" political process. 2 And____________________