of 1915 in Champagne, it was shown that there were three
important causes of non-success namely, absence of the element
of surprise, unsatisfactory cooperation between infantry and
artillery, and the fact that the whole enterprise was on too
small a scale. In a brief review of later offensives it has been
possible to show how these defects were gradually overcome,
how artillery gradually dominated the tactical theories of the day,
but at the same time rendered surprise an impossibility, until
at Cambrai it seemed that the solution had at last been found.
But Cambrai was itself something of an experiment, and on too
small a scale to have a really decisive result.. As is always the
case in war, the armies of the Central Powers had been passing
all the time through the same evolutionary stages as those of
the Entente. The minds of Hindenburg and Ludendorff were
busy with exactly the same tactical problems as those which
daily occupied the thoughts of British, French and Italian
commanders. After the great failure in front of Verdun in the
early part of 1916 there was no German offensive on the Franco-
British front until March 1918, but much experience had been
gained in the East and in Italy; moreover, there can be no doubt
that Ludendorff's penetrating mind had grasped the reasons for
the failure of successive attacks by the Entente armies, as well
as the real meaning and significance of Cambrai. Profiting by
the experience of others always a most difficult thing to do, but
perhaps particularly so in war he had refrained from himself
taking the initiative until the Russian debS.de had put him in a
position to do so on a really grand scale. By March 1918 he
was able to mass some 80 well-trained divisions for offensive
operations in the West, and this in turn enabled him to attack
the British III. and V. Armies on a front of 80 kilometres.
The mere fact of being able to stage an attack on this scale gave the German armies a great prospect of success, and elimi- nated the third of the causes of failure enumerated above. The other two were more difficult to deal with, but in order to secure surprise Hindenburg and Ludendorff decided to dispense with that counter-battery work and artillery preparation which on the Somme, at Arras and round Ypres, no less than in Champagne, had disclosed the Allies' intentions while at the same time rendering the ground difficult, and sometimes impos- sible, to the attacking infantry. Five hours only were allotted to the artillery bombardment, and in this time wire was to be cut and the enemy guns to be mastered at least sufficiently to allow the infantry to advance. Such was the solution of the second problem the introduction of surprise and the decision to attempt so much in so short a time was perhaps the bolder since the German army must accomplish without tanks and on a much larger scale what the British had accomplished with them at their last attempt. 1 The third difficulty that of cooperation was overcome by the provision of large numbers of light trench mortars, 2 which, as well as a proportion of field guns, accompanied the infantry advance, as well as by an elaborate system of light signals by which the infantry might indicate their position and wishes to the artillery.
Thus each of the difficulties of 1915 found an appropriate solution in 1918. The attack was on a sufficiently large scale to allow considerable room for manoeuvre within the salient which was inevitably formed; the infantry received adequate
- support from the artillery, at least for several days, and until it
was itself exhausted by appalling loss and by the breakdown of supplies (for which the efficiency of the British air service was largely responsible) on congested roads; lastly, a tactical surprise had been effected, with the result that the troops which bore the brunt of the first onslaught were without reinforcements for several days; and this was principally due to the fact that there was no preliminary bombardment to indicate definitely the portion of the front which had been selected for attack.
1 The facts that the German design had been foreseen at Versailles and that the evidence of prisoners confirmed the British forecast in no way detract from the tactical skill with which Ludendorff's plans were prepared and executed, or from the value of the lesson.
- It has been said that the Germans possessed 15,000 of these
weapons in 1918.
Nevertheless, notwithstanding the admitted skill and care with which the German commanders had prepared their plans and the colossal scale upon which they carried them out, they, no less than the Entente, failed to reach decisive results. What they did was to show what it was possible to achieve with the materials which science and industry had by this time placed in the hands of the commanders in the field. They had shattered many of the shibboleths of trench warfare and shown that infantry was still the conquering arm. In doing so, they not only exhausted their own man-power, but set loose a new set of tactical ideas which were seized by the genius of Marshal Foch and eventually assisted in their own destruction; for, just as Germany had learnt from the Allied successes and failures of 1915, 1916 and 1917, so the Allies in their turn learned from the German success and failure of 1918.
Foch in Command. It is not necessary here to trace the steps which led to the appointment of Marshal Foch to the Supreme Command in March 1918. All that remains to be done is to follow the effect of that appointment upon the tactical history of the war on the western front. Even after the first great German drive had been checked in front of Amiens, the initiative remained with the Germans for more than three months while the great soldier who was now in command of the Allied armies was reorganizing his forces and making his own plans. During this period the German attack tactics were unaltered, but each successive effort was a little weaker than that which preceded it, and the only new development was the skill with which one French commander evaded the enemy's blow, surrendered his forward posts and crushed the assaulting lines as they approached his real fighting positions. Such tactics were only possible at a specially favoured portion of the front, but that they were brought into play at the right place and at the right time was another sign that trench warfare was becoming a thing of the past. Meanwhile Foch was maturing his plans, and when historians of the future, with full documentary evidence at their disposal, examine the record of these days it may be found that the marshal's greatest claim to fame is that he, the student of the past, still retained his belief in the war of movement and in the counter-stroke as the strongest weapon of defence.
Twice in the earlier stages of the war great counter-strokes had been delivered with marked success, but for two years they had not been repeated, and the side which had attacked had been met only with passive defence. In 1914 the German sweep towards Paris had been outflanked by Manoury and thrust back to the line of the Aisne, and nearly two years later the costly attempt to capture Verdun had been checkmated by the opening of the first battle of the Somme, though not until it had been in progress for several months. Since that date there had been the two great Entente attacks of April and July 1917 and the German attack of March 1918. In 1918 troops for the attack were provided by withdrawal from Russia, where they were no longer required; but in 1917 it had been necessary to denude important parts of the front in order to release the number of divisions necessary for offensive action, and to trust for defence to a highly developed trench system which could be held by comparatively few troops, so that there was a considerable risk of counter-attack. It is remarkable that, against an enemy trained in the German traditions, the assailant was always able to impose his will, and the defence became largely a question of railways and transportation. The relief of troops on a fighting front, their replacement by others, and their transport to a quiet part of the line became a regular tactical system to which the French gave the name of roulement. It was a new feature of war, completely contrary to the peace teaching of every country, but one which was the logical result of the elaborate preparations which were then considered necessary before it was possible to burst through a modern system of field fortification. It was not until Marshal Foch assumed command that the grand tactics of defence underwent any real change, and perhaps he was fortunate in that Cambrai and the March offensive had shown what was possible, and that, as the result of the movement which had taken place, the positions held by the opposing forces
