British army on its S. wing, cut it off from the French, and by pressing on its right flank and attacking it from the front cause it to waver and fall to pieces and force it back to the coast. What was that but a " Cannae operation," in which a natural ob- stacle the sea took the place of Hasdrubal? A second natural obstacle the Somme was to serve the German left wing, advancing in deeply echeloned formation, as a protection against a French flank attack. The difficulties presented by the un- avoidable traversing of the ruined Alberich area, and the Somme battlefield with its craters, were fully recognized, particularly as regards shelter and the bringing up of fresh drafts. These diffi- culties would diminish, however, as soon as the operation reached out into the country as yet untouched by battle, to the W. of this zone. Only in case that did not succeed would the disadvantages of this wilderness as a permanent stopping-place become evident.
On one point indeed, and that the most vital, did Ludendorff's procedure differ from Schlieffen's form of strategy. The German attack was directed, not against the whole enemy front, but against a limited section only. The perfectly obvious reason for this was that the fighting forces and battle requirements came nowhere near being sufficient for such an undertaking. The question is, whether it would have been possible and desirable to carry out the Schlieffen idea in a general sense, if not literally. The aim of the attack on the whole front was to engage all the enemy's forces, particularly his reserves, who might otherwise in due course intercept and choke off the break-through, just as it became ripe for operative development. Ludendorff saw the danger of this quite clearly, and sought to avert it by feint attacks on as many parts of the front as possible, by threats of a great attack and by partial actions on a small scale. These measures undoubtedly had a great temporary effect. Petain refused to send more than 3 divisions to Haig's hard-pressed front on March 24, on the ground that Ludendorff's main attack was to be at Reims, where the artillery battle had already begun. But the effect of these measures lasted only a short time, of course, and were limited as to material. The enemy's reserves were not absorbed, but could still, though after much delay, be moved and brought up to the decisive battlefield. It would certainly have been more in accordance with the Schlieffen idea if, alongside of these feint attacks and reaching beyond them, a serious diversion had been undertaken shortly before the main attack began. It would have had to be carried out by a strong but strictly limited number of troops, to give promise of a prompt initial success and to have a limited objective. For this purpose, so far as the British front was concerned the " St. George " operations across the Lys depression were not possible, on account of the season and weather conditions. In Flanders the circum- stances were similar. There remained only the VI. Army front between the La Bassee canal and Arras. It may be questioned whether the attack, which was tactically very difficult here, would have succeeded to a sufficient extent in its object of tying up the strong enemy reserves. There were, in any case, important reasons for the decision not to make a preliminary diversion at this point in order to have a more powerful force to put in to the decisive battle itself.
On the French front things were essentially different. It was of the utmost importance that if the proposed operation were to succeed it should be secured from a strong flank attack by the French, and not be brought to a standstill by a relief offensive on a large scale. It is known that Ludendorff had intended the VII. Army to execute a diversion. But this was to take place after the great offensive had begun, and could not therefore have the effect of drawing off strong reserves of the enemy in a wrong direction and holding them fast there. The diversion would also be too closely in touch with the main attack as re- gards space. Several places had been proposed for a German diversion on the French front, such as the Chemin des Dames region and Champagne. Verdun was less suitable on account of the large force that would be required. The front of Duke Albrecht's army group in Alsace (Breuschtal) also seemed suit- able. If the attack were made there the French reserves would be far away from the critical point of the coming decisive battle.
As far as the actual number of good attack divisions was con- cerned there were ample forces available. The spring offensive opened on March 21 with 62 divisions. Up to the close on April 5, 92 divisions had been put in, and even so not all the divisions available for attack purposes had been used up. This powerful mass would probably have been even more effective if it had not been used exclusively and directly for the break-through opera- tion itself, but had been devoted in part to putting the French reserves into fetters at another place. General Buat even goes so far as to say that only by a series of diversions, delivered simul- taneously or in rapid succession in different places, could the operative success of the break-through have been guaranteed. He admits however and herein lies the point of the decision that this method was impracticable for Ludendorff owing to lack of sufficient forces. For it was a question not only of having in readiness the required number of divisions but the massing of artillery, flame-throwers, airmen, munitions, motor columns and numerous other necessities of war. Of these the Supreme Com- mand had not enough available for the furnishing of a powerful diversion immediately before or at the time of the main attack, if this was delivered on the scale planned. A diversion was there- fore only conceivable in the event of a reduction of area or material in the main attack. But any reduction of this sort would have lessened the chance of a great and rapid victory on the spot selected, the indispensable condition of the undertaking.
The conclusions are that not only was the application of Schlieffen's theoretical ideal form for an operative break- through the attack on the whole front out of the question for Ludendorff, but the attempt to conform to the underlying idea in a modified form by executing a diversion on a large scale was not to be recommended in the spring of 1918, since the forces were insufficient. In practice the disciple was forced by existing circumstances to fall short of the master's theoretical standard laid down in time of peace.
But is it, as Buat thinks, the fact that the idea of the operative break-through was foredoomed to failure? Strategy is a system of makeshifts. This fundamental saying of Moltke's was fully appreciated by Count Schlieffen. Ludendorff had to act in accordance with it. If the enemy's reserves could not be tied up in another place and kept away from the scene of the main battle, and if, therefore, they might be expected to turn up there sooner or later, the work of the battle and the execution of the operative scheme would certainly be made more difficult. Whether the attacker, in spite of this, would have the strength to achieve not only a tactical victory, but the complete strategical success, which involved the destruction of the enemy, was the supreme question which only the god of battles himself could answer. If the reward due to his passionate efforts was withheld, he would have to moderate those efforts and reconcile himself to closing down the offensive and accepting the battle of materiel and its attendant overstraining of his forces. The first great hammer- blow would then at least have had the effect of a diversion. It would have accomplished its aim according to the Schlieffen idea of operations by shattering and absorbing a large portion of the enemy fighting forces. It was then for the command to show its skill in launching, as quickly as possible, a new attack to bring about a decision with the yet unused forces from another well- selected and prepared position.
This then was the problem of the break-through as it presented itself to the German Supreme Command.
The Great Battle. As the Germans had not the means for equipping all the divisions on the western front equally, and as the essential value of the different divisions also varied for rea- sons connected with drafting, they were forced to limit them- selves to a certain number of those which seemed most suitable for the purpose of the attack. These were the so-called mobile divisions. Altogether S 2 of these divisions were made available for the beginning of the Michael operation. Besides these there were 10 divisions in the line directly taking a part in the attack, making in all 62 divisions. They were distributed as follows: XVII. Army, 15 mobile divisions and 2 divisions in the line; II. Army, 15 mobile divisions and 3 divisions in the line; XVIII.
