THE word "command" has a charm in the art of war peculiar to itself, and in fact to this element belongs a great part, perhaps half the influence which ground exercises on the use of troops. Here many of the sacred relics of military erudition have their root, as, for instance, commanding positions, key positions, strategic manœuvres, etc. We shall take as clear a view of the subject as we can without prolixity, and pass in review the true and the false, reality and exaggeration.
Every exertion of physical force if made upwards is more difficult than if it is made in the contrary direction (downwards); consequently it must be so in fighting; and there are three evident reasons why it is so. First, every height may be regarded as an obstacle to approach; secondly, although the range is not perceptibly greater in shooting down from a height, yet, all geometrical relations being taken into consideration, we have a better chance of hitting than in the opposite case; thirdly, an elevation gives a better command of view. How all these advantages unite themselves together in battle we are not concerned with here; we collect the sum total of the advantages which tactics derives from elevation of position and combine them in one whole which we regard as the first strategic advantage.
But the first and last of these advantages that have been enumerated must appear once more as advantages of strategy itself, for we march and reconnoitre in strategy as well as in tactics; if, therefore, an elevated position is an obstacle to the approach of those on lower ground, that is the second; and the better command of view which this elevated position affords is the third advantage which strategy may derive in this way.
Of these elements is composed the power of dominating, overlooking, commanding; from these sources springs the sense of superiority and security which is felt in standing on the brow of a hill and looking at the enemy below, and the feeling of weakness and apprehension which pervades the minds of those below. Perhaps the total impression made is at the same time stronger than it ought to be, because the advantage of the higher ground strikes the senses more than the circumstances which modify that advantage. Perhaps the impression made surpasses that which the truth warrants, in which case the effect of imagination must be regarded as a new element, which exaggerates the effect produced by an elevation of ground.
At the same time the advantage of greater facility of movement is not absolute, and not always in favour of the side occupying the higher position; it is only so when his opponent wishes to attack him; it is not if the combatants are separated by a great valley, and it is actually in favour of the army on the lower ground if both wish to fight in the plain (battle of Hohenfriedberg). Also the power of overlooking, or command of view, has likewise great limitations. A wooded country in the valley below, and often the very masses of the mountains themselves on which we stand, obstruct the vision. Countless are the cases in which we might seek in vain on the spot for those advantages of an elevated position which a map would lead us to expect; and we might often be led to think we had only involved ourselves in all kinds of disadvantages, the very opposite of the advantages we counted upon. But these limitations and conditions do not abrogate or destroy the superiority which the more elevated position confers, both on the defensive and offensive. We shall point out, in a few words, how this is the case with each.
Out of the three strategic advantages of the more elevated ground, the greater tactical strength, the more difficult approach, and the better view, the first two are of such a nature that they belong really to the defensive only; for it is only in holding firmly to a position that we can make use of them, whilst the other side (offensive) in moving cannot remove them and take them with him; but the third advantage can be made use of by the offensive just as well as by the defensive.
From this it follows that the more elevated ground is highly important to the defensive, and as it can only be maintained in a decisive way in mountainous countries, therefore it would seem to follow, as a consequence, that the defensive has an important advantage in mountain positions. How it is that, through other circumstances, this is not so in reality, we shall show in the chapter on the defence of mountains.
We must first of all make a distinction if the question relates merely to commanding ground at one single point, as, for example, a position for an army; in such case the strategic advantages rather merge in the tactical one of a battle fought under advantageous circumstances; but if now we imagine a considerable tract of country—suppose a whole province—as a regular slope, like the declivity at a general watershed, so that we can make several marches, and always hold the upper ground, then the strategic advantages become greater, because we can now use the advantages of the more elevated ground not only in the combination of our forces with each other for one particular combat, but also in the combination of several combats with one another. Thus it is with the defensive.
As regards the offensive, it enjoys to a certain extent the same advantages as the defensive from the more elevated ground; for this reason that the stragetic attack is not confined to one act like the tactical. The strategic advance is not the continuous movement of a piece of wheelwork; it is made in single marches with a longer or shorter interval between them, and at each halting point the assailant is just as much acting on the defensive as his adversary.
Through the advantage of a better view of the surrounding country, an elevated position confers, in a certain measure, on the offensive as well as the defensive, a power of action which we must not omit to notice; it is the facility of operating with separate masses. For each portion of a force separately derives the same advantages which the whole derives from this more elevated position; by this—a separate corps, let it be strong or weak in numbers, is stronger than it would otherwise be, and we can venture to take up a position with less danger than we could if it had not that particular property of being on an elevation. The advantages which are to be derived from such separate bodies of troops is a subject for another place.
If the possession of more elevated ground is combined with other geographical advantages which are in our favour, if the enemy finds himself cramped in his movements from other causes, as, for instance, by the proximity of a large river, such disadvantages of his position may prove quite decisive, and he may feel that he cannot too soon relieve himself from such a position. No army can maintain itself in the valley of a great river if it is not in possession of the heights on each side by which the valley is formed.
The possession of elevated ground may therefore become virtually command, and we can by no means deny that this idea represents a reality. But nevertheless the expressions "commanding ground," "sheltering position," "key of the country," in so far as they are founded on the nature of heights and descents, are hollow shells without any sound kernel. These imposing elements of theory have been chiefly resorted to in order to give a flavour to the seeming commonplace of military combinations; they have become the darling themes of learned soldiers, the magical wands of adepts in strategy, and neither the emptiness of these fanciful conceits, nor the frequent contradictions which have been given to them by the results of experience have sufficed to convince authors, and those who read their books, that with such phraseology they are drawing water in the leaky vessel of the Danaides. The conditions have been mistaken for the thing itself, the instrument for the hand. The occupation of such and such a position or space of ground, has been looked upon as an exercise of power like a thrust or a cut, the ground or position itself as a substantive quantity; whereas the one is like the lifting of the arm, the other is nothing but the lifeless instrument, a mere property which can only realise itself upon an object, a mere sign of plus or minus which wants the figures or quantities. This cut and thrust, this object, this quantity, is a victorious battle; it alone really counts; with it only can we reckon; and we must always have it in view, as well in giving a critical judgment in literature as in real action in the field.
Consequently, if nothing but the number and value of victorious combats decides in war, it is plain that the comparative value of the opposing armies and ability of their respective leaders again rank as the first points for consideration, and that the part which the influence of ground plays can only be one of an inferior grade.