How did Clausewitz influence the war planning before 1914? Partly because none of the major powers possessed anything comparable to the United States’ National Security Council, many of their war plans did not match strategy to particular political objectives. Russia pledged itself to a rapid advance into Germany in order to help its ally France, without forecasting where that advance might stop or how it might end. Austro-Hungarian leaders seem to have failed to grasp that they would have inadequate forces to destroy Serbia unless Russia stayed out of the war until it was too late. The French Plan XVII did aim directly at France’s political objective, the recovery of Alsace-Lorraine. But the German general staff, acting without much political input, had under Schlieffen thought matters out more carefully. War against the Franco-Russian alliance required a quick, complete victory over one enemy or the other, and Schlieffen had chosen France. Reading On War, Book 8, Chapter 4, he would have noticed three recommended means of defeating an enemy: the destruction of its army, the occupation of its capital, and the delivery of an effective blow against a powerful ally. Leaving aside the third, he had written a plan to accomplish the first two objectives. The envelopment of the French Army by the advance through Belgium would destroy it and allow him to capture Paris far more quickly than the elder Moltke had in 1870-1. Schlieffen was dead by 1914, of course, and the younger Moltke had the extraordinary luck of fighting against a French war plan that could not have been better designed to help him had it been written in Berlin. However, he came a cropper. The Schlieffen plan sought a decisive battle deep in the interior of France — a strategy which, Clausewitz had warned, could indeed produce a victory with maximum political consequences, but which was also more difficult to achieve than a victory at the frontier. And so it was. The extraordinary advance of the German...