The new strategy was first practised by our Third Army in its November Drive against Cambrai; that drive failed for want of sufficient reinforcements to back it up. Until that time the Allies had always gone after what were known as “limited objectives,” such as high ground, trench-systems, villages, salients. When the objective had been taken, the attack rested. The Vimy Ridge was a limited objective. We didn’t want to break the Hun line; what we desired was the Ridge, because it commanded a great enemy plain on the other side. For two months before we actually struck, we advertised the fact that we were going to strike by the intensity of our incessant shell-fire. Systematically, day by day and night by night, we cut the enemy’s wire-entanglements, blew up his dumps, mined beneath his front-line, pounded his cement machine-gun emplacements, harassed his means of communication and stole his morale by making his life perilous and wretched. He knew as well as we did what was planned; his only uncertainty was as to the exact hour at which the attack was to be launched. We kept him wearily guessing, and wore his nerves to a frazzle by putting on intense bombardments at inconvenient times. Usually these bombardments took place at dawn, lasted for fifteen minutes and had all the appearance of being the genuine zero hour. When our barrage had descended, he would man his trenches, call up his reserves and set all the machinery for his counterthrust working. Then, as suddenly as it had started, the hell would die down into the intensest quiet. The new strategy does not advertise the point to be attacked. It does not cut wire-entanglements with shell-fire many days before the show commences; it tramples down obstacles with battalions of tanks at the very moment that the infantry are advancing. It does not set out to capture a given and solitary object; its ambition is to double up the enemy’s line and to penetrate as far as success will allow. The new strategy is in all things more stealthy, more tiger-like, more reckless, more deadly; its most dangerous feature is the use which it makes of surprise.