CHAPTER XIV
A TACTICAL APPRECIATION
The battle of Messines may be looked upon as the high-water mark of the artillery attack, which was first developed by the British Army during the battle of the Somme. The time, however, was approaching when a change of tactics became imperative on account of the enemy having learnt his lesson. To appreciate what this question involves is of some interest, especially so, as in the tank was eventually discovered a means of overcoming the counter-measures now adopted by the enemy.[24]
The main characteristic which differentiates the German defensive tactics of 1917 from those of 1916 would appear to lie in the grouping of their men rather than in the siting of their trenches.
In 1916 the major portion of the German Army was placed in the frontal defensive belt because security was sought for in the maintenance of an unbroken front. In 1917, however, this security was more economically guaranteed by holding behind this front, instead of in it, a large reserve which could strike at any opponent who broke through.
This reversion to the “big idea” and the abandonment of the smaller one, namely, that war is a “series of local emergency measures,” placed a further difficulty in the way of the attacker. In 1917 it was no longer a question of breaking through a defensive line as in 1914, or a zone of defences as in 1915 and 1916, but of exhausting the enemy’s reserves before undertaking either of these operations with decisive effect.
This could now only be accomplished by hitting the enemy at a point which he must hold on to because of its importance or of surprising him at points where he did not expect to be attacked. If such points were not selected all he need do was to fall back as he had already done in March, and so dislocate our operations, by temporarily denying us the use of our guns.
As hitherto, the change we have always most carefully to watch for is any change the enemy is likely to carry out in his artillery tactics, and the following is apparently what the German was now doing.
Having learnt in 1916 and the first half of 1917 that if the attacker makes up his mind to do it, he can carry, by means of artillery and infantry alone, several lines of trenches in one bound, it stood to reason that the German General Staff would not continue to jeopardise its artillery by so placing it that it could be pounded to pieces during our preliminary bombardment.