Scott Silverstone has written an important book about a well-worn subject. Although that may seem a peculiar characterization, it illustrates the persistence of the problem dissected in his effective analysis. Acting preemptively to arrest a looming international threat to the national well-being has always presented policymakers with a simple, appealing, and seemingly logical solution to a growing existential problem. As this study demonstrates, preemption embodies the classic simple and inadequate answer to a complex question. As many have discovered, launching preventive war does not work as a matter of policy or strategy. Carl von Clausewitz wisely pointed out, “No one starts a war—or rather, no one in his senses ought to do so—without first being clear in his mind what he intends to achieve by that war and how he intends to conduct it” (On War, ed. and trans. Michael Howard and Peter Paret [1975], p. 579).

The problem becomes more complex when one realizes that the clarity and goals Clausewitz demands of the major actors rarely survive first contact with the adversary. Preemption or preventive war have rarely worked as policy, and their operational outcome frequently marks the beginning rather than the end of a protracted conflict. However, the appeal of a preventive solution resides precisely in its seeming logic and simplicity. Policymakers, such as former American President George W. Bush, frequently see this paradox as an option in crisis situations, in spite of its track record. This paradox forms the central point of Silverstone's study, which examines both specific cases of preemption and the views of major military and political players on this alternative when it seemed an option. Silverstone also explores cases in which current scholars still view preemption with sympathy and occasionally lament the lack of this action as a lost opportunity.

Hitler's remilitarization of the Rhineland in 1936, in violation of both Versailles and Locarno, takes center stage in Silverstone's interesting analysis. What should France have done, especially in view of Germany's rearmament and growing military power? The Wehrmacht had not yet reached sufficient strength to resist a French counter-strike. Why not throw the Germans back immediately and reveal Hitler's weakness? Could the French have counted on support from Great Britain? Might that have destabilized the Nazi regime sufficiently? All through his analysis, the author uses this 1936 crisis as a paradigm. The French chose not to respond with force, a decision often seen as a missed opportunity by some contemporaries as well as scholars reviewing the events since the war. Examining the French decision and the policies embraced by other Western powers at the time, Silverstone looks at other cases for perspective, taking the reader back to the Peloponnesian War, the 1923 occupation of the Ruhr by France in response to unpaid war reparations, and the policies and perspectives of statesmen such as Otto von Bismarck and Gustav Stresemann. In the case of Athens and Sparta, preemption did not provide the security sought, and in the Ruhr, the French compounded the desire for revenge the Germans already felt as a result of the Versailles settlement.

As a historian rather than a social scientist, I found the case of Stresemann and Bismarck particularly interesting and informative. Many historians view historical analysis of a well-documented set of circumstances as the best possible lessons-learned tool for any policymaker. The past does not repeat itself, but humans do react in remarkably similar ways when called upon to address similar problems and threats. In my role as the chief historian of a major intelligence agency, I designed my program to produce studies that would inform the Department of Defense and the intelligence community in just that way.

I take issue with the author of this study not on content, presentation, or analysis. Rather, I question the power of his methodology to permit him to offer the strong policy advice I believe he sought to provide in embarking on this journey. Silverstone's analysis clearly reveals the false promise of the preventive option and dissects, in a very penetrating manner, the flaws in the option as revealed over the centuries. He also effectively reminds us of the seriously complex national security problems faced by nation-states and the need for solutions that can, in a practical and effective manner, address that complexity. He correctly calls upon his readers to embrace care and the humility that comes with the uncertainty the future inspires. However, this historian would suggest that casting policy options in conclusion as a counterfactual debate can weaken an analysis. Sound policy options can emerge from the way Bismarck and Stresemann understood threats, conflict, and personal dynamics. A close examination of the background these leaders brought to the problems they faced as well as the broad context born of experience they fashioned to support their policy analysis can provide concrete policy options more often than one might think. This very worthwhile study should provoke a further discussion on these matters for the simple reason that the subject is war and lives are in the balance.