IN a lost battle the power of an army is broken, the moral to a greater degree than the physical. A second battle, unless fresh favourable circumstances come into play, would lead to a complete defeat, perhaps, to destruction. This is a military axiom. According to the usual course the retreat is continued up to that point where the equilibrium of forces is restored, either by reinforcements, or by the protection of strong fortresses, or by great divisions of the country, or by a separation of the enemy's force. The magnitude of the losses sustained, the extent of the defeat, but still more the character of the enemy, will bring nearer or put off the instant of this equilibrium. How many instances may be found of a beaten army rallied again at a short distance, without its circumstances having altered in any way since the battle. The cause of this may be traced to the moral deficiency of the adversary, or to the preponderance gained in the battle not having been sufficient to make a lasting impression.
To profit by this weakness or mistake of the enemy, not to yield one inch breadth more than the pressure of circumstances demands, but above all things, in order to keep up the moral forces to as advantageous a point as possible, a slow retreat, offering incessant resistance, and bold courageous counterstrokes, whenever the enemy seeks to gain any excessive advantages, are absolutely necessary. Retreats of great generals and of armies inured to war have always resembled the retreat of a wounded lion, and such is, undoubtedly, also the best theory.
It is true that at the moment of quitting a dangerous position we have often seen trifling formalities observed which caused a waste of time, and were, therefore, attended with danger, whilst in such cases everything depends on getting out of the place speedily. Practised generals reckon this maxim a very important one. But such cases must not be confounded with a general retreat after a lost battle. Whoever then thinks by a few rapid marches to gain a start, and more easily to recover a firm standing, commits a great error. The first movements should be as small as possible, and it is a maxim in general not to suffer ourselves to be dictated to by the enemy. This maxim cannot be followed without bloody combats with the enemy at our heels, but the maxim is worth the sacrifice; without it we get into an accelerated pace which soon turns into a headlong rush, and costs merely in stragglers more men than rear-guard combats would have cost, and besides that extinguishes the last remnants of courageous spirit.
A strong rear guard composed of picked troops, commanded by the bravest general, and supported by the whole army at critical moments, a careful utilisation of ground, strong ambuscades wherever the boldness of the enemy's advanced guard, and the ground, afford opportunity; in short, the preparation and the system of regular small battles,—these are the means of following this principle.
The difficulties of a retreat are naturally greater or less according as the battle has been fought under more or less favourable circumstances, and according as it has been more or less obstinately contested. The battle of Jena and Belle Alliance show how impossible anything like a regular retreat may become, if the last man is used up against a powerful enemy.
Now and again it has been suggested (Lloyd Bulow) to divide for the purpose of retreating, therefore to retreat in separate divisions or even eccentrically. Such a separation as is made merely for convenience, and along with which concentrated action continues possible and is kept in view, is not what we now refer to: any other kind is extremely dangerous, contrary to the nature of the thing, and therefore a great error. Every lost battle is a principle of weakness and disorganisation; and the first and immediate desideratum is to concentrate, and in concentration to recover order, courage, and confidence. The idea of harassing the enemy by separate corps on both flanks at the moment when he is following up his victory, is a perfect anomaly; a faint-hearted pedant might be overawed by his enemy in that manner, and for such a case it may answer; but where we are not sure of this failing in our opponent it is better let alone. If the strategic relations after a battle require that we should cover ourselves right and left by detached corps, so much must be done, as from circumstances is unavoidable, but this fractioning must always be regarded as an evil, and we are seldom in a state to commence it the day after the battle itself.
If Frederick the Great after the battle of Collin, and the raising of the siege of Prague retreated in three columns, that was done not out of choice, but because the position of his forces, and the necessity of covering Saxony, left him no alternative. Buonaparte after the battle of Brienne, sent Marmont back to the Aube, whilst he himself passed the Seine, and turned towards Troyes; but that this did not end in disaster, was solely owing to the circumstance that the Allies, instead of pursuing, divided their forces in like manner, turned with the one part (Blucher) towards the Marne, while with the other (Schwartzenberg), from fear of being too weak, they advanced quite slowly.