But on the other hand, he who now wishes to, and can retreat cannot easily be forced to give battle. Now as the advantages to the aggressor from this retreat are often not sufficient, and a substantial victory is a matter of urgent necessity for him, in that way the few means which there are to compel such an opponent also to give battle are often sought for and applied with particular skill.
The principal means for this are—first surrounding the enemy so as to make his retreat impossible, or at least so difficult that it is better for him to accept battle; and, secondly, surprising him. This last way, for which there was a motive formerly in the extreme difficulty of all movements, has become in modern times very inefficacious.
From the pliability and manoeuvring capabilities of troops in the present day, one does not hesitate to commence a retreat even in sight of the enemy, and only some special obstacles in the nature of the country can cause serious difficulties in the operation.
As an example of this kind the battle of Neresheim may be given, fought by the Archduke Charles with Moreau in the Rauhe Alp, August 11, 1796, merely with a view to facilitate his retreat, although we freely confess we have never been able quite to understand the argument of the renowned general and author himself in this case.
The battle of Rosbach(*) is another example, if we suppose the commander of the allied army had not really the intention of attacking Frederick the Great.
(*) November 5, 1757.
Of the battle of Soor,(*) the King himself says that it was only fought because a retreat in the presence of the enemy appeared to him a critical operation; at the same time the King has also given other reasons for the battle.
(*) Or Sohr, September 30, 1745.
On the whole, regular night surprises excepted, such cases will always be of rare occurrence, and those in which an enemy is compelled to fight by being practically surrounded, will happen mostly to single corps only, like Mortier’s at Durrenstein 1809, and Vandamme at Kulm, 1813.
(*) Clausewitz still uses the word “die Hauptschlacht” but modern usage employs only the word “die Schlacht” to designate the decisive act of a whole campaign—encounters arising from the collision or troops marching towards the strategic culmination of each portion or the campaign are spoken of either as “Treffen,” i.e., “engagements” or “Gefecht,” i.e., “combat” or “action.” Thus technically, Gravelotte was a “Schlacht,” i.e., “battle,” but Spicheren, Woerth, Borny, even Vionville were only “Treffen.”
What is a battle? A conflict of the main body, but not an unimportant one about a secondary object, not a mere attempt which is given up when we see betimes that our object is hardly within our reach: it is a conflict waged with all our forces for the attainment of a decisive victory.