 Reflecting memories of World War I, the French General Staff had developed the concept of "la puissance du feu" ("the power of fire"), the power of artillery dug in and sheltered by concrete and steel, to inflict devastating losses on an attacking force.French planning for war with Germany was always based on the assumption that the war would be "la guerre de longue durée" (the war of the long duration), in which the superior economic resources of the Allies would gradually grind the Germans down.The fact that the "Wehrmacht" embraced the strategy of Blitzkrieg (Lightning War) with the vision of swift wars in which Germany would win quickly via a knock-out blow, was a testament to the fundamental soundness of the concept of "la guerre de longue durée".