We began this study on the effectiveness of military institutions in the belief that historians have an obligation to examine the issues involved in why some military forces succeed, while others fail. If we have not succeeded fully inour goal, we believe that the essays in this volume have at least suggested the dimensions of the issues. There are no easy answers, no quick fixes, no simple formulas for the achievement of military effectiveness. While one of the authors of the summarizing essays in Volume 3 suggests that ‘one can doubt whether any other profession [than the military] in these seven nations during the same period would have received such poor ratings by similarly competent outside observers,’ these studies also suggest how intractable,complex, and resistant to analysis and calculation are the problems raised by war.

This study involves seven nations over three distinct time periods: the First World War (Volume 1), the interwar period (Volume 2), and the Second World War (Volume 3). We have asked each one of the historians examining these twenty–one case studies to follow the direction provided in a guidance essay (the first chapter in Volume 1). That essay asked our historians to examine what we believe to be the four distinct levels of war: the political, the strategic, the operational, and the tactical from the point of view of their national case studies. Thus, there are consistent themes running through all of the essays.