"It is a FIRST maxim NEVER to remain perfectly passive, but to fall upon the enemy in front and flank, even when he is in the act of making an attack upon us."[67]
And again—
"A swift and vigorous assumption of the offensive—the flashing sword of vengeance—is the most brilliant point in the defensive. He who does not at once think of it at the right moment, or rather he who does not from the first include this transition in his idea of the defensive, will never understand its superiority as a form of war."[68] Von Caemmerer comments thus: "And this conception of the defence by Clausewitz has become part and parcel of our army—everywhere, strategically and tactically, he who has been forced into a defensive attitude at once thinks how he can arrange a counter-attack. I am thus unable to see how the way in which Clausewitz has contrasted Attack and Defence could in any way paralyse the spirit of enterprise." Von Caemmerer also justly remarks that, as Clausewitz always insisted both in strategy and tactics, neither Attack nor Defence is pure, but oscillates between the two forms; and as the Attack is frequently temporarily reduced to defend itself, and also as no nation can be sure of never being invaded by a superior coalition, it is most desirable to encourage a belief in the strength of the Defence, if properly used. In this I think that Wellington would probably have agreed. Certainly Austerlitz and Waterloo were examples of battles such as Clausewitz preferred.
Still, one must admit that Clausewitz's chapter on "The Relations of the Offensive and Defensive to each other in Tactics," Book VII. Chapter 2, is the least convincing chapter of his work.
Strategically, the argument is stronger. It always seems to me that we must remember that Clausewitz had taken part in the defensive-offensive in its strongest, most absolute and unlimited form, on the greatest possible scale—the Moscow campaign and the ruin (consummated before a single flake of snow fell) of the Grand Army. If he had lived to complete the revision of his works, it always seems to me that he would have made his theory undeniable by stating that the defensive is the strongest form of war, if unlimited by space. What, for instance, would have happened if the Japanese had tried to march through Siberia on to St. Petersburg?
But, after all, which of the two is absolutely the stronger form of war, attack or defence, is merely a theoretical abstraction, for, practically, the choice is always settled for us by the pressing necessity of circumstances. And, in this connection, let us always bear in mind Clausewitz's dictum: "A swift and vigorous assumption of the offensive—the flashing sword of vengeance—is the most brilliant point in the defensive."
The Inner Line
A second disputed point is Clausewitz's alleged preference, as a rule, for the Inner Line in strategy. But it is necessary to remember that that was only due to the conditions of his time, before railways and telegraphs, when it was difficult to communicate between columns acting on concentric lines. And he is not in any way wedded to the Inner Line, like Jomini, but only when circumstances are favourable. He has many sentences from which we may infer that, had he lived in railway and telegraph days, his strategy, like Moltke's, his most distinguished pupil, would have aimed at envelopment as a rule. For to bring up troops rapidly by several railways necessitates a broad strategic front, and Clausewitz especially lays down rapidity as his second great principle, and says—
"If the concentration of the forces would occasion detours and loss of time, and the danger of advancing by separate lines is not too great, then the same may be justifiable on these grounds; for to effect an unnecessary concentration of the forces would be contrary to the second principle we have laid down (i.e. 'to act as swiftly as possible')."[69] Also: "Such separation into several columns as is absolutely necessary must be made use of for the disposition of the tactical attack in the enveloping form, for that form is natural to the attack, and must not be disregarded without good reason."[70] Also: "It is sufficient now if the concentration takes place during the action." So that while the conditions of his time led Clausewitz to prefer close concentration and the Inner Line, like Napoleon, yet his reflections led him to propound the germ of the strategy of Moltke. Substitute for Clausewitz's close concentration this: "As close concentration, the combined movements regulated by telegraph, as is compatible with the utmost use of the railways and the greatest rapidity" (as he would certainly have said), and we arrive at Moltke's strategy.