We shall have to consider how, in future, to preserve for war the character of the war of movement, all the more so since, in the World War, it has only been by the war of movement that we have reaped decisive results. It will, of course, be accompanied by many of the features of entrenched warfare, and, in consequence of the necessity of bringing up and setting in operation the numerous present-day methods of attack, it will be slow. An approximate illustration of this is furnished by the course of the operations in East Prussia and Lithuania and of the Germano-Austro-Hungarian offensive in Galicia and Poland in the summer of 1915, as well as by the campaigns in Serbia, Transylvania, and Roumania; and the rapid progress of operations in these instances furnishes convincing proof that the resolute will of a leader, combined with the valour of his troops, is capable of overcoming those difficulties which the bringing up of their numerous weapons of war entails upon a modern army. For this kind of warfare we ourselves had received just the appropriate training, and we were in fact superior to all the other armies. Such a form of warfare is decisive, and will always remain decisive; the years which we have spent in our trenches do not alter this fact in any way. That spirit of the offensive which is peculiar to our army we must study to preserve by every means in our power. It has achieved striking results in this War, and has recently once again proved its effectiveness in the summer of 1917 in Eastern Galicia and in the defensive battles in North France and Flanders. But we must not lose sight of the fact that from time to time, at the beginning, a systematic adherence to offensive tactics, even where the situation rendered it more advisable to make full use of the strength which the effectiveness of present-day weapons gives to defensive tactics, cost us a heavy sacrifice. In any case the War has proved that the assertion often made in time of peace that the spade digs the grave of the offensive is not correct. This assertion may be compared with the saying which was current in the Prussian army, to its very great detriment, before the battle of Jena: "Skirmishing encourages the scoundrel in human nature." From the military point of view Goethe is right when he says: "For it is just where ideas are lacking that a phrase is most welcome." Catch-words are always prejudicial in their effect, and most of all so when it is a question of the blood of our sons and brothers. It was not only King Frederick who expressed his sense of the importance of selecting strong positions. Napoleon, the representative of the most uncompromising offensive, told the officers of his engineer-corps in 1806 that in the coming campaign against Prussia he intended that a very great quantity of earth should be shovelled up.[9] And Moltke writes[10]: