Many historians, analysts, and policymakers believe that war plans conceived in peacetime lead to war, despite the wishes of civilian leaders. This is the "Guns of August" school of thought which is prompted by the role of war plans in precipitating World War I. As Sir Basil Liddell Hart has noted, "The statesman may continue to send telegrams, but they are merely waste paper. The military machine has completely taken charge." (1)
War plans may also determine strategy in war. "Those who make or endorse the plans," as some observe, "are in effect determining the strategy both for peace and for the opening phases, at least, of a future war; they are giving the commands which really count." (2) Extant plans might affect war management under certain circumstances. "When no one knows what to do in a crisis," Richard Betts commented, "a contingency plan can virtually set the terms and focus the decisional debate. Advocates of an existing plan have an advantage over opponents who do not have one of their own." (3)
The historical record shows that while war plans do not actually cause war--civilian political decisions do--they can affect wartime outcomes. The problem is that there is no consensus on exactly how. Thus it makes sense to examine how war planning affects military effectiveness.
Why should one care about the impact of war planning? The implications of this question are clear: if the views of the Guns of August school are correct, civilian policymakers must be concerned about the nature and content of peacetime plans made by military professionals lest these plans undermine crisis management and lead to accidental wars. Conversely, if Helmuth von Moltke (the Elder) was right, that no war plan ever survives contact with the enemy, civilian and military leaders ought to be wary of the fact that substantial resources devoted to peacetime war planning are being wasted because of its irrelevancy.
The general consequences of war plans have not been fully explored, however, because most of the extant literature consists largely of historical studies of individual plans. While many excellent monographs and essays look at the particulars of great power war planning before the World Wars and the Cold War, most fail to derive and test general propositions about the effects of these plans on wartime performance or offer concrete policy recommendations. There has been no attempt to link these inquiries to the larger conceptual debates in the social sciences. One exception was the spurt of interest in the role of pre-war planning prior to World War I. During the early and mid-1980s scholars examined the origins of that conflict for clues about how World War III might be inadvertently triggered. They also regarded it as an illustration of the spiral model of international relations, which holds that wars often start by accident, in contrast to the reigning deterrence model of the Cold War period, which maintains that they start because one side believes it can gain more by armed conflict than by peace. As will become clear, however, the assessment of the role of war plans in causing World War I in the spiral model, and its generalizations about plans precipitating accidental war in other cases, are flawed. Therefore we do not yet have a persuasive theory about when and how plans matter.
Many regard World War I as evidence that war plans can cause wars. Until recently, it was widely believed that it was an accidental war, at least in terms of the desires of the civilian leaders of the great powers. As Prime Minister David Lloyd George put it, "the nations slithered over the brink into the boiling cauldron of war." (4) There are two variations on this theme of accidental war: that civilian leaders misperceived the intentions of their neighbors as well as the relative advantages of offensive and defensive military technologies, or that the military organizations of each state ran amok. …