The battle of the Marne closed a definite phase of the Great War, and perhaps——in so far as it was marked by open and rapid movement, and as it finally exposed certain gross military errors——a phase of warfare in general. A fresh examination of the plans of the preceding years and the events of the preceding month immensely enhances the interest of the whole development; for it shows the real “miracle of the Marne” to have been an uprush of intelligence and patriotic will in which grave faults of strategy and tactics were corrected, and the victory to be the logical reward of a true conception, executed with unfailing skill through a new instrument created while the conditions of the struggle were being equalised. In whatever sense we may speak of a “greatest” battle of history, this was assuredly, of all clashes of force, that in which reason was most conspicuously vindicated. Insanely presumptuous as was her ambition of reducing France, Russia, and Britain, Germany had at the outset some remarkable advantages. Chief among these must be counted the power of surprise, due to her long secret preparation, and a complete unity of command in face of dispersed Allies. The German forces concentrated on the west were not numerically superior to those of France, Britain, and Belgium; their effective superiority was considerable. Half of the active corps, which alone the French expected as troops of shock, were doubled with thoroughly trained reserve formations, giving a mass of attack of 34 corps, instead of 22, a difference larger than the two armies of the enveloping movement. Their strength was also increased by a clear superiority in several branches of armament and field service (the French field-gun and the use by the Allies of the French railways being notable exceptions), and in some particulars of tactical practice, especially the prudent use of field defences. The basic idea being to strike France down before Russia and Britain could effectually interfere, speed was a principal condition of success; and the plan of the Western campaign was probably the only one on which it could be realised. One-third of the whole force was to hold the old Franco-German frontier in a provisional defence, while one-third attacked through Luxembourg and the Belgian Ardennes, and the remainder was thrown across the Meuse and the open plain of Flanders, toward the French capital. This unprecedented enlargement of the offensive front, the outstanding feature of the plan, secured the most rapid deployment of the maximum forces; it alone could yield the great element of surprise; it alone provided the opportunity of envelopment dear to the German military mind. Its boldness, aided by terrorism in the invaded regions, astounded the world, and so seemed to favour the scheme of conquest. It might ultimately provoke a full development of British power; even in case of failure, it would cripple France and Belgium for many years.