CHAPTER XIV - Flank Positions
We have only allotted to this prominent conception, in the world of ordinary military theory, a special chapter in dictionary fashion, that it may the more easily be found; for we do not believe that anything independent in itself is denoted by the term.
Every position which is to be held, even if the enemy passes by it, is a flank position; for from the moment that he does so it can have no other efficacy but that which it exercises on the enemy’s strategic flank. Therefore, necessarily, all strong positions are flank positions as well; for as they cannot be attacked, the enemy accordingly is driven to pass them by, therefore they can only have a value by their influence on his strategic flank. The direction of the proper front of a strong position is quite immaterial, whether it runs parallel with the enemy’s strategic flank, as Colberg, or at right angles as Bunzelwitz and Drissa, for a strong position must front every way.
But it may also be desirable still to maintain a position which is not unassailable, even if the enemy passes by it, should its situation, for instance, give us such a preponderating advantage in the comparative relations of the lines of retreat and communication, that we can not only make an efficacious attack on the strategic flank of the advancing enemy, but also that the enemy alarmed for his own retreat is unable to seize ours entirely; for if that last is not the case, then because our position is not a strong, that is not an unassailable one, we should run the risk of being obliged to fight without having the command of any retreat.
The year 1806 affords an example which throws a light on this. The disposition of the Prussian army, on the right bank of the Saal, might in respect to Buonaparte’s advance by Hof, have become in every sense a flank position, if the army had been drawn up with its front parallel to the Saal, and there, in that position, waited the progress of events.
If there had not been here such a disproportion of moral and physical powers, if there had only been a Daun at the head of the French army, then the Prussian position might have shown its efficacy by a most brilliant result. To pass it by was quite impossible; that was acknowledged by Buonaparte, by his resolution to attack it; in severing from it the line of retreat even Buonaparte himself did not completely succeed, and if the disproportion in physical and moral relations had not been quite so great, that would have been just as little practicable as the passing it by, for the Prussian army was in much less danger from its left wing being overpowered than the French army would have been by the defeat of their left wing. Even with the disproportion of physical and moral power as it existed, a resolute and sagacious exercise of the command would still have given great hopes of a victory. There was nothing to prevent the Duke of Brunswick from making arrangements on the 13th, so that on the morning of the 14th, at day-break, he might have opposed 80,000 men to the 60,000 with which Buonaparte passed the Saal, near Jena and Dornburg. Had even this superiority in numbers, and the steep valley of the Saal behind the French not been sufficient to procure a decisive victory, still it was a fortunate concurrence of circumstances, and if with such advantages no successful decision could be gained, no decision was to be expected in that district of country; and we should, therefore, have retreated further, in order to gain reinforcements and weaken the enemy.
The Prussian position on the Saal, therefore, although assailable, might have been regarded as a flank position in respect to the great road through Hof; but like every position which can be attacked, that property is not to be attributed to it absolutely, because it would only have become so if the enemy had not attempted to attack it.
Still less would it bespeak a clear idea if those positions which cannot be maintained after the enemy has passed by them, and from which, in consequence of that, the defensive seeks to attack the assailant’s flank, were called flank positions merely because his attack is directed against a flank; for this flank attack has hardly anything to do with the position itself, or, at least, is not mainly produced by its properties, as is the case in the action against a strategic flank.
It appears from this that there is nothing new to establish with regard to the properties of a flank position. A few words only on the character of the measure may properly be introduced here; we set aside, however, completely strong positions in the true sense, as we have said enough about them already.
A flank position which is not assailable is an extremely efficacious instrument, but certainly just on that account a dangerous one. If the assailant is checked by it, then we have obtained a great effect by a small expenditure of force; it is the pressure of the finger on the long lever of a sharp bit. But if the effect is too insignificant, if the assailant is not stopped, then the defensive has more or less imperilled his retreat, and must seek to escape either in haste and by a detour—consequently under very unfavourable circumstances, or he is in danger of being compelled to fight without any line of retreat being open to him. Against a bold adversary, having the moral superiority, and seeking a decisive solution, this means is therefore extremely hazardous and entirely out of place, as shown by the example of 1806 above quoted. On the other hand, when used against a cautious opponent in a war of mere observation, it may be reckoned one of the best means which the defensive can adopt. The Duke Ferdinand’s defence of the Weser by his position on the left bank, and the well-known positions of Schmotseifen and Landshut are examples of this; only the latter, it is true, by the catastrophe which befell Fouqué’s corps in 1760, also shows the danger of a false application.
CHAPTER XV - Defence of Mountains
The influence of mountains on the conduct of war is very great; the subject, therefore, is very important for theory. As this influence introduces into action a retarding principle, it belongs chiefly to the defensive. We shall therefore discuss it here in a wider sense than that conveyed by the simple conception, defence of mountains. As we have discovered in our consideration of the subject results which run counter to general opinion in many points, we shall therefore be obliged to enter into rather an elaborate analysis of it.
We shall first examine the tactical nature of the subject, in order to gain the point where it connects itself with strategy.
The endless difficulty attending the march of large columns on mountain roads, the extraordinary strength which a small post obtains by a steep scarp covering its front, and by ravines right and left supporting its flanks, are unquestionably the principal causes why such efficacy and strength are universally attributed to the defence of mountains, so that nothing but the peculiarities in armament and tactics at certain periods has prevented large masses of combatants from engaging in it.
When a column, winding like a serpent, toils its way through narrow ravines up to the top of a mountain, and passes over it at a snail’s pace, artillery and train-drivers, with oaths and shouts, flogging their over-driven cattle through the narrow rugged roads, each broken waggon has to be got out of the way with indescribable trouble, whilst all behind are detained, cursing and blaspheming, every one then thinks to himself, Now if the enemy should appear with only a few hundred men, he might disperse the whole. From this has originated the expression used by historical writers, when they describe a narrow pass as a place where “a handful of men might keep an army in check.” At the same time, every one who has had any experience in war knows, or ought to know, that such a march through mountains has little or nothing in common with the attack of these same mountains, and that therefore to infer from the difficulty of marching through mountains that the difficulty of attacking them must be much greater is a false conclusion.
It is natural enough that an inexperienced person should thus argue, and it is almost as natural that the art of war itself for a certain time should have been entangled in the same error, for the fact which it related to was almost as new at that time to those accustomed to war as to the uninitiated. Before the Thirty Years’ War, owing to the deep order of battle, the numerous cavalry, the rude fire-arms, and other peculiarities, it was quite unusual to make use of formidable obstacles of ground in war, and a formal defence of mountains, at least by regular troops, was almost impossible. It was not until a more extended order of battle was introduced, and that infantry and their arms became the chief part of an army, that the use which might be made of hills and valleys occurred to men’s minds. But it was not until a hundred years afterwards, or about the middle of the eighteenth century, that the idea became fully developed.
The second circumstance, namely, the great defensive capability which might be given to a small post planted on a point difficult of access, was still more suited to lead to an exaggerated idea of the strength of mountain defences. The opinion arose that it was only necessary to multiply such a post by a certain number to make an army out of a battalion, a chain of mountains out of a mountain.
It is undeniable that a small post acquires an extraordinary strength by selecting a good position in a mountainous country. A small detatchment, which would be driven off in the level country by a couple of squadrons, and think itself lucky to save itself from rout or capture by a hasty retreat, can in the mountains stand up before a whole army, and, as one might say, with a kind of tactical effrontery exact the military honour of a regular attack, of having its flank turned, etc., etc. How it obtains this defensive power, by obstacles to approach, points d’appui for its flanks, and new positions which it finds on its retreat, is a subject for tactics to explain; we accept it as an established fact.
It was very natural to believe that a number of such posts placed in a line would give a very strong, almost unassailable front, and all that remained to be done was to prevent the position from being turned by extending it right and left until either flank-supports were met with commensurate with the importance of the whole, or until the extent of the position itself gave security against turning movements. A mountainous country specially invites such a course by presenting such a succession of defensive positions, each one apparently better than another, that one does not know where to stop; and therefore it ended in all and every approach to the mountains within a certain distance being guarded, with a view to defence, and ten or fifteen single posts, thus spread over a space of about ten miles or more, were supposed to bid defiance to that odious turning movement. Now as the connection between these posts was considered sufficiently secure by the intervening spaces, being ground of an impassable nature (columns at that time not being able to quit the regular roads), it was thought a wall of brass was thus presented to the enemy. As an extra precaution, a few battalions, some horse artillery, and a dozen squadrons of cavalry, formed a reserve to provide against the event of the line being unexpectedly burst through at any point.
No one will deny that the prevalence of this idea is shown by history, and it is not certain that at this day we are completely emancipated from these errors.
The course of improvement in tactics since the Middle Ages, with the ever increasing strength of armies, likewise contributed to bring mountainous districts in this sense more within the scope of military action.
The chief characteristic of mountain defence is its complete passivity; in this light the tendency towards the defence of mountains was very natural before armies attained to their present capability of movement. But armies were constantly becoming greater, and on account of the effect of fire-arms began to extend more and more into long thin lines connected with a great deal of art, and on that account very difficult, often almost impossible, to move. To dispose, in order of battle, such an artistic machine, was often half a day’s work, and half the battle; and almost all which is now attended to in the preliminary plan of the battle was included in this first disposition or drawing up. After this work was done it was therefore difficult to make any modifications to suit new circumstances which might spring up; from this it followed that the assailant, being the last to form his line of battle, naturally adapted it to the order of battle adopted by the enemy, without the latter being able in turn to modify his in accordance. The attack thus acquired a general superiority, and the defensive had no other means of reinstating the balance than that of seeking protection from the impediments of ground, and for this nothing was so favourable in general as mountainous ground. Thus it became an object to couple, as it were, the army with a formidable obstacle of ground, and the two united then made common cause. The battalion defended the mountain, and the mountain the battalion; so the passive defence through the aid of mountainous ground became highly efficacious, and there was no other evil in the thing itself except that it entailed a greater loss of freedom of movement, but of that quality they did not understand the particular use at that time.
When two antagonistic systems act upon each other, the exposed, that is, the weak point on the one side always draws upon itself the blows from the other side. If the defensive becomes fixed, and as it were, spell-bound in posts, which are in themselves strong, and can not be taken, the aggressor then becomes bold in turning movements, because he has no apprehension about his own flanks. This is what took place—The turning, as it was called, soon became the order of the day: to counteract this, positions were extended more and more; they were thus weakened in front, and the offensive suddenly turned upon that part: instead of trying to outflank by extending, the assailant now concentrated his masses for attack at some one point, and the line was broken. This is nearly what took place in regard to mountain defences according to the latest modern history.
The offensive had thus again gained a preponderance through the greater mobility of troops; and it was only through the same means that the defence could seek for help. But mountainous ground by its nature is opposed to mobility, and thus the whole theory of mountain defence experienced, if we may use the expression, a defeat like that which the armies engaged in it in the Revolutionary war so often suffered.
But that we may not reject the good with the bad, and allow ourselves to be carried along by the stream of commonplace to assertions which, in actual experience, would be refuted a thousand times by the force of circumstances, we must distinguish the effects of mountain defence according to the nature of the cases.
The principal question to be decided here, and that which throws the greatest light over the whole subject is, whether the resistance which is intended by the defence of mountains is to be relative or absolute—whether it is only intended to last for a time, or is meant to end in a decisive victory. For a resistance of the first kind mountainous ground is in a high degree suitable, and introduces into it a very powerful element of strength; for one of the latter kind, on the contrary, it is in general not at all suitable, or only so in some special cases.
In mountains every movement is slower and more difficult, costs also more time, and more men as well, if within the sphere of danger. But the loss of the assailant in time and men is the standard by which the defensive resistance is measured. As long as the movement is all on the side of the offensive so long the defensive has a marked advantage; but as soon as the defensive resorts to this principle of movement also, that advantage ceases. Now from the nature of the thing, that is to say, on tactical grounds, a relative resistance allows of a much greater degree of passivity than one which is intended to lead to a decisive result, and it allows this passivity to be carried to an extreme, that is, to the end of the combat, which in the other case can never happen. The impeding element of mountain ground, which as a medium of greater density weakens all positive activity, is, therefore, completely suited to the passive defence.
We have already said that a small post acquires an extraordinary strength by the nature of the ground; but although this tactical result in general requires no further proof, we must add to what we have said some explanation. We must be careful here to draw a distinction between what is relatively and what is absolutely small. If a body of troops, let its size be what it may, isolates a portion of itself in a position, this portion may possibly be exposed to the attack of the whole body of the enemy’s troops, therefore of a superior force, in opposition to which it is itself small. There, as a rule, no absolute but only a relative defence can be the object. The smaller the post in relation to the whole body from which it is detached and in relation to the whole body of the enemy, the more this applies.
But a post also which is small in an absolute sense, that is, one which is not opposed by an enemy superior to itself, and which, therefore, may aspire to an absolute defence, a real victory, will be infinitely better off in mountains than a large army, and can derive more advantage from the ground as we shall show further on.
Our conclusion, therefore, is, that a small post in mountains possesses great strength. How this may be of decisive utility in all cases which depend entirely on a relative defence is plain of itself; but will it be of the same decisive utility for the absolute defence by a whole army? This is the question which we now propose to examine.
First of all we ask whether a front line composed of several posts has, as has hitherto been assumed, the same strength proportionally as each post singly. This is certainly not the case, and to suppose so would involve one of two errors.
In the first place, a country without roads is often confounded with one which is quite impassable. Where a column, or where artillery and cavalry cannot march, infantry may still, in general, be able to pass, and even artillery may often be brought there as well, for the movements made in a battle by excessive efforts of short duration are not to be judged of by the same scale as marches. The secure connection of the single posts with one another rests therefore on an illusion, and the flanks are in reality in danger.
Or next it is supposed, a line of small posts, which are very strong in front, are also equally strong on their flanks, because a ravine, a precipice, etc., etc., form excellent supports for a small post. But why are they so?—not because they make it impossible to turn the post, but because they cause the enemy an expenditure of time and of force, which gives scope for the effectual action of the post. The enemy who, in spite of the difficulty of the ground, wishes, and in fact is obliged, to turn such a post, because the front is unassailable requires, perhaps, half-a-day to execute his purpose, and cannot after all accomplish it without some loss of men. Now if such a post can be succoured, or if it is only designed to resist for a certain space of time, or lastly, if it is able to cope with the enemy, then the flank supports have done their part, and we may say the position had not only a strong front, but strong flanks as well. But it is not the same if it is a question of a line of posts, forming part of an extended mountain position. None of these three conditions are realised in that case. The enemy attacks one point with an overwhelming force, the support in rear is perhaps slight, and yet it is a question of absolute resistance. Under such circumstances the flank supports of such posts are worth nothing.
Upon a weak point like this the attack usually directs its blows. The assault with concentrated, and therefore very superior forces, upon a point in front, may certainly be met by a resistance, which is very violent as regards that point, but which is unimportant as regards the whole. After it is overcome, the line is pierced, and the object of the attack attained.
From this it follows that the relative resistance in mountain warfare is, in general, greater than in a level country, that it is comparatively greatest in small posts, and does not increase in the same measure as the masses increase.
Let us now turn to the real object of great battles generally—to the positive victory which may also be the object in the defence of mountains. If the whole mass, or the principal part of the force, is employed for that purpose, then the defence of mountains changes itself eo ipso into a defensive battle in the mountains. A battle, that is the application of all our powers to the destruction of the enemy is now the form, a victory the object of the combat. The defence of mountains which takes place in this combat, appears now a subordinate consideration, for it is no longer the object, it is only the means. Now in this view, how does the ground in mountains answer to the object?
The character of a defensive battle is a passive reaction in front, and an increased active reaction in rear; but for this the ground in mountains is a paralysing principle. There are two reasons for this: first, want of roads affording means of rapidly moving in all directions, from the rear towards the front, and even the sudden tactical attack is hampered by the unevenness of ground; secondly, a free view over the country, and the enemy’s movements is not to be had. The ground in mountains, therefore, ensures in this case to the enemy the same advantages which it gave to us in the front, and deadens all the better half of the resistance. To this is to be added a third objection, namely the danger of being cut off. Much as a mountainous country is favourable to a retreat, made under a pressure exerted along the whole front, and great as may be the loss of time to an enemy who makes a turning movement in such a country, still these again are only advantages in the case of a relative defence, advantages which have no connection with the decisive battle, the resistance to the last extremity. The resistance will last certainly somewhat longer, that is until the enemy has reached a point with his flank-columns which menaces or completely bars our retreat. Once he has gained such a point then relief is a thing hardly possible. No act of the offensive which we can make from the rear can drive him out again from the points which threaten us; no desperate assault with our whole mass can clear the passage which he blocks. Whoever thinks he discovers in this a contradiction, and believes that the advantages which the assailant has in mountain warfare, must also accrue to the defensive in an attempt to cut his way through, forgets the difference of circumstances. The corps which opposes the passage is not engaged in an absolute defence, a few hours’ resistance will probably be sufficient; it is, therefore, in the situation of a small post. Besides this, its opponent is no longer in full possession of all his fighting powers; he is thrown into disorder, wants ammunition, etc. Therefore, in any view, the chance of cutting through is small, and this is the danger that the defensive fears above all; this fear is at work even during the battle, and enervates every fibre of the struggling athlete. A nervous sensibility springs up on the flanks, and every small detachment which the aggressor makes a display of on any wooded eminence in our rear, is for him a new lever, helping on the victory.
These disadvantages will, for the most part, disappear, leaving all the advantages, if the defence of a mountain district consists in the concentrated disposition of the army on an extensive mountain plateau. There we may imagine a very strong front; flanks very difficult of approach, and yet the most perfect freedom of movement, both within and in rear of the position. Such a position would be one of the strongest that there can be, but it is little more than an illusion, for although most mountains are more easily traversed along their crests than on their declivities, yet most plateaux of mountains are either too small for such a purpose, or they have no proper right to be called plateaux, and are so termed more in a geological, than in a geometrical sense.
For smaller bodies of troops, the disadvantages of a defensive position in mountains diminish as we have already remarked. The cause of this is, that such bodies take up less space, and require fewer roads for retreat, etc., etc. A single hill is not a mountain system, and has not the same disadvantages. The smaller the force, the more easily it can establish itself on a single ridge or hill, and the less will be the necessity for it to get entangled in the intricacies of countless steep mountain gorges.
CHAPTER XVI - Defence of Mountains (Continued)
We now proceed to the strategic use of the tactical results developed in the preceding chapter. We make a distinction between the following points:
1. A mountainous district as a battle-field.
2. The influence which the possession of it exercises on other parts of the country.
3. Its effect as a strategic barrier.
4. The attention which it demands in respect to the supply of the troops.
The first and most important of these heads, we must again subdivide as follows:
a. A general action.
b. Inferior combats.
1. A mountain system as a battle-field.
We have shown in the preceding chapter how unfavourable mountain ground is to the defensive in a decisive battle, and, on the other hand, how much it favours the assailant. This runs exactly counter to the generally received opinion; but then how many other things there are which general opinion confuses; how little does it draw distinctions between things which are of the most opposite nature! From the powerful resistance which small bodies of troops may offer in a mountainous country, common opinion becomes impressed with an idea that all mountain defence is extremely strong, and is astonished when any one denies that this great strength is communicated to the greatest act of all defence, the defensive battle. On the other hand, it is instantly ready, whenever a battle is lost by the defensive in mountain warfare, to point out the inconceivable error of a system of cordon war, without any regard to the fact that in the nature of things such a system is unavoidable in mountain warfare. We do not hesitate to put ourselves in direct opposition to such an opinion, and at the same time we must mention, that to our great satisfaction, we have found our views supported in the works of an author whose opinion ought to have great weight in this matter; we allude to the history of the campaigns of 1796 and 1797, by the Archduke Charles, himself a good historical writer, a good critic, and above all, a good general.
We can only characterise it as a lamentable position when the weaker defender, who has laboriously, by the greatest effort, assembled all his forces, in order to make the assailant feel the effect of his love of Fatherland, of his enthusiasm and his ability, in a decisive battle when he on whom every eye is fixed in anxious expectation, having betaken himself to the obscurity of thickly veiled mountains, and hampered in every movement by the obstinate ground, stands exposed to the thousand possible forms of attack which his powerful adversary can use against him. Only towards one single side is there still left an open field for his intelligence, and that is in making all possible use of every obstacle of ground; but this leads close to the borders of the disastrous war of cordons, which, under all circumstances, is to be avoided. Very far therefore from seeing a refuge for the defensive, in a mountainous country, when a decisive battle is sought, we should rather advise a general in such a case to avoid such a field by every possible means.
It is true, however, that this is sometimes impossible; but the battle will then necessarily have a very different character from one in a level country: the disposition of the troops will be much more extended in most cases twice or three times the length; the resistance more passive, the counter blow much less effective. These are influences of mountain ground which are inevitable; still, in such a battle the defensive is not to be converted into a mere defence of mountains; the predominating character must be a concentrated order of battle in the mountains, in which everything unites into one battle, and passes as much as possible under the eye of one commander, and in which there are sufficient reserves to make the decision something more than a mere warding off, a mere holding up of the shield. This condition is indispensable, but difficult to realise; and the drifting into the pure defence of mountains comes so naturally, that we cannot be surprised at its often happening; the danger in this is so great that theory cannot too urgently raise a warning voice.
Thus much as to a decisive battle with the main body of the army.
For combats of minor significance and importance, a mountainous country, on the other hand, may be very favourable, because the main point in them is not absolute defence, and because no decisive results are coupled with them. We may make this plainer by enumerating the objects of this reaction.
a. Merely to gain time. This motive occurs a hundred times: always in the case of a defensive line formed with the view of observation; besides that, in all cases in which a reinforcement is expected.
b. The repulse of a mere demonstration or minor enterprise of the enemy. If a province is guarded by mountains which are defended by troops, then this defence, however weak, will always suffice to prevent partisan attacks and expeditions intended to plunder the country. Without the mountains, such a weak chain of posts would be useless.
c. To make demonstrations on our own part. It will be some time yet before general opinion with respect to mountains will be brought to the right point; until then an enemy may at any time be met with who is afraid of them, and shrinks back from them in his undertakings. In such a case, therefore, the principal body may also be used for the defence of a mountain system. In wars carried on with little energy or movement, this state of things will often happen; but it must always be a condition then that we neither design to accept a general action in this mountain position, nor can be compelled to do so.
d. In general, a mountainous country is suited for all positions in which we do not intend to accept any great battle, for each of the separate parts of the army is stronger there, and it is only the whole that is weaker; besides, in such a position, it is not so easy to be suddenly attacked and forced into a decisive battle.
e. Lastly, a mountainous country is the true region for the efforts of a people in arms. But while national risings should always be supported by small bodies of regular troops, on the other hand, the proximity of a great army seems to have an unfavourable effect upon movements of this kind; this motive, therefore, as a rule, will never give occasion for transferring the whole army to the mountains.
Thus much for mountains in connection with the positions which may be taken up there for battle.
2. The influence of mountains on other parts of the country.
Because, as we have seen, it is so easy in mountainous ground to secure a considerable tract of territory by small posts, so weak in numbers that in a district easily traversed they could not maintain themselves, and would be continually exposed to danger; because every step forward in mountains which have been occupied by the enemy must be made much more slowly than in a level country, and therefore cannot be made at the same rate with him therefore the question, Who is in possession? is also much more important in reference to mountains than to any other tract of country of equal extent. In an open country, the possession may change from day to day. The mere advance of strong detachments compels the enemy to give up the country we want to occupy. But it is not so in mountains; there a very stout resistance is possible by much inferior forces, and for that reason, if we require a portion of country which includes mountains, enterprises of a special nature, formed for the purpose, and often necessitating a considerable expenditure of time as well as of men, are always required in order to obtain possession. If, therefore, the mountains of a country are not the theatre of the principal operations of a war, we cannot, as we should were it the case of a district of level country, look upon the possession of the mountains as dependent on and a necessary consequence of our success at other parts.
A mountainous district has therefore much more independence, and the possession of it is much firmer and less liable to change. If we add to this that a ridge of mountains from its crests affords a good view over the adjacent open country, whilst it remains itself veiled in obscurity, we may therefore conceive that when we are close to mountains, without being in actual possession of them, they are to be regarded as a constant source of disadvantage a sort of laboratory of hostile forces; and this will be the case in a still greater degree if the mountains are not only occupied by the enemy, but also form part of his territory. The smallest bodies of adventurous partisans always find shelter there if pursued, and can then sally forth again with impunity at other points; the largest bodies, under their cover, can approach unperceived, and our forces must, therefore, always keep at a sufficient distance if they would avoid getting within reach of their dominating influence if they would not be exposed to disadvantageous combats and sudden attacks which they cannot return.
In this manner every mountain system, as far as a certain distance, exercises a very great influence over the lower and more level country adjacent to it. Whether this influence shall take effect momentarily, for instance in a battle (as at Maltsch on the Rhine, 1796) or only after some time upon the lines of communication, depends on the local relations; whether or not it shall be overcome through some decisive event happening in the valley or level country, depends on the relations of the armed forces to each other respectively.
Buonaparte, in 1805 and 1809, advanced upon Vienna without troubling himself much about the Tyrol; but Moreau had to leave Swabia in 1796, chiefly because he was not master of the more elevated parts of the country, and too many troops were required to watch them. In campaigns, in which there is an evenly balanced series of alternate successes on each side, we shall not expose ourselves to the constant disadvantage of the mountains remaining in possession of the enemy: we need, therefore, only endeavour to seize and retain possession of that portion of them which is required on account of the direction of the principal lines of our attack; this generally leads to the mountains being the arena of the separate minor combats which take place between forces on each side. But we must be careful of overrating the importance of this circumstance, and being led to consider a mountain-chain as the key to the whole in all cases, and its possession as the main point. When a victory is the object sought; then it is the principal, object; and if the victory is gained, other things can be regulated according to the paramount requirement of the situation.
3. Mountains considered in their aspect of a strategic barrier.
We must divide this subject under two heads.
The first is again that of a decisive battle. We can, for instance, consider the mountain chain as a river, that is, as a barrier with certain points of passage, which may afford us an opportunity of gaining a victory, because the enemy will be compelled by it to divide his forces in advancing, and is tied down to certain roads, which will enable us with our forces concentrated behind the mountains to fall upon fractions of his force. As the assailant on his march through the mountains, irrespective of all other considerations, cannot march in a single column because he would thus expose himself to the danger of getting engaged in a decisive battle with only one line of retreat, therefore, the defensive method recommends itself certainly on substantial grounds. But as the conception of mountains and their outlets is very undefined, the question of adopting this plan depends entirely on the nature of the country itself, and it can only be pointed out as possible whilst it must also be considered as attended with two disadvantages, the first is, that if the enemy receives a severe blow, he soon finds shelter in the mountains; the second is, that he is in possession of the higher ground, which, although not decisive, must still always be regarded as a disadvantage for the pursuer.
We know of no battle given under such circumstances unless the battle with Alvinzi in 1796 can be so classed. But that the case may occur is plain from Buonaparte’s passage of the Alps in the year 1800, when Melas might and should have fallen on him with his whole force before he had united his columns.
The second influence which mountains may have as a barrier is that which they have upon the lines of communication if they cross those lines. Without taking into account what may be done by erecting forts at the points of passage and by arming the people, the bad roads in mountains at certain seasons of the year may of themselves alone prove at once destructive to an army; they have frequently compelled a retreat after having first sucked all the marrow and blood out of the army. If, in addition, troops of active partisans hover round, or there is a national rising to add to the difficulties, then the enemy’s army is obliged to make large detachments, and at last driven to form strong posts in the mountains and thus gets engaged in one of the most disadvantageous situations that can be in an offensive war.
4. Mountains in their relation to the provisioning of an army.
This is a very simple subject, easy to understand. The opportunity to make the best use of them in this respect is when the assailant is either obliged to remain in the mountains, or at least to leave them close in his rear.
These considerations on the defence of mountains, which, in the main, embrace all mountain warfare, and, by their reflection, throw also the necessary light on offensive war, must not be deemed incorrect or impracticable because we can neither make plains out of mountains, nor hills out of plains, and the choice of a theatre of war is determined by so many other things that it appears as if there was little margin left for considerations of this kind. In affairs of magnitude it will be found that this margin is not so small. If it is a question of the disposition and effective employment of the principal force, and that, even in the moment of a decisive battle, by a few marches more to the front or rear an army can be brought out of mountain ground into the level country, then a resolute concentration of the chief masses in the plain will neutralise the adjoining mountains.
We shall now once more collect the light which has been thrown on the subject, and bring it to a focus in one distinct picture.
We maintain and believe we have shown, that mountains, both tactically and strategically, are in general unfavourable to the defensive, meaning thereby, that kind of defensive which is decisive, on the result of which the question of the possession or loss of the country depends. They limit the view and prevent movements in every direction; they force a state of passivity, and make it necessary to stop every avenue or passage, which always leads more or less to a war of cordons. We should therefore, if possible, avoid mountains with the principal mass of our force, and leave them on one side, or keep them before or behind us.
At the same time, we think that, for minor operations and objects, there is an element of increased strength to be found in mountain ground; and after what has been said, we shall not be accused of inconsistency in maintaining that such a country is the real place of refuge for the weak, that is, for those who dare not any longer seek an absolute decision. On the other hand again, the advantages derived from a mountainous country by troops acting an inferior rôle cannot be participated in by large masses of troops.
Still all these considerations will hardly counteract the impressions made on the senses. The imagination not only of the inexperienced but also of all those accustomed to bad methods of war will still feel in the concrete case such an overpowering dread of the difficulties which the inflexible and retarding nature of mountainous ground opposes to all the movements of an assailant, that they will hardly be able to look upon our opinion as anything but a most singular paradox. Then again, with those who take a general view, the history of the last century (with its peculiar form of war) will take the place of the impressions of the senses, and therefore there will be but few who will not still adhere to the belief that Austria, for example, should be better able to defend her states on the Italian side than on the side of the Rhine. On the other hand, the French who carried on war for twenty years under a leader both energetic and indifferent to minor considerations, and have constantly before their eyes the successful results thus obtained, will, for some time to come, distinguish themselves in this as well as in other cases by the tact of a practised judgment.
Does it follow from this that a state would be better protected by an open country than by mountains, that Spain would be stronger without the Pyrenees; Lombardy more difficult of access without the Alps, and a level country such as North Germany more difficult to conquer than a mountainous country? To these false deductions we shall devote our concluding remarks.
We do not assert that Spain would be stronger without the Pyrenees than with them, but we say that a Spanish army, feeling itself strong enough to engage in a decisive battle, would do better by concentrating itself in a position behind the Ebro, than by fractioning itself amongst the fifteen passes of the Pyrenees. But the influence of the Pyrenees on war is very far from being set aside on that account. We say the same respecting an Italian army. If it divided itself in the High Alps it would be vanquished by each resolute commander it encountered, without even the alternative of victory or defeat; whilst in the plains of Turin it would have the same chance as every other army. But still no one can on that account suppose that it is desirable for an aggressor to have to march over masses of mountains such as the Alps, and to leave them behind. Besides, a determination to accept a great battle in the plains, by no means excludes a preliminary defence of the mountains by subordinate forces, an arrangement very advisable in respect to such masses as the Alps and Pyrenees. Lastly, it is far from our intention to argue that the conquest of a mountainous country is easier than that of a level(*) one, unless a single victory sufficed to prostrate the enemy completely. After this victory ensues a state of defence for the conqueror, during which the mountainous ground must be as disadvantageous to the assailant as it was to the defensive, and even more so. If the war continues, if foreign assistance arrives, if the people take up arms, this reaction will gain strength from a mountainous country.
It is here as in dioptrics, the image represented becomes more luminous when moved in a certain direction, not, however, as far as one pleases, but only until the focus is reached, beyond that the effect is reversed.
If the defensive is weaker in the mountains, that would seem to be a reason for the assailant to prefer a line of operations in the mountains. But this will seldom occur, because the difficulties of supporting an army, and those arising from the roads, the uncertainty as to whether the enemy will accept battle in the mountains, and even whether he will take up a position there with his principal force, tend to neutralise that possible advantage.
(*) As it is conceived that the words “ebenen” and “gebirgigen” in this passage in the original have by some means become transposed, their equivalents—level and mountainous—are here placed in the order in which it is presumed the author intended the words to stand.—Tr.
CHAPTER XVII - Defence of Mountains (continued)
In the fifteenth chapter we spoke of the nature of combats in mountains, and in the sixteenth of the use to be made of them by strategy, and in so doing we often came upon the idea of mountain defence, without stopping to consider the form and details of such a measure. We shall now examine it more closely.
As mountain systems frequently extend like streaks or belts over the surface of the earth, and form the division between streams flowing in different directions, consequently the separation between whole water systems, and as this general form repeats itself in the parts composing that whole, inasmuch as these parts diverge from the main chain in branches or ridges, and then form the separation between lesser water systems; hence the idea of a system of mountain defence has naturally founded itself in the first instance, and afterwards developed itself, upon the conception of the general form of mountains, that of an obstacle, like a great barrier, having greater length than breadth. Although geologists are not yet agreed as to the origin of mountains and the laws of their formation, still in every case the course of the waters indicates in the shortest and surest manner the general form of the system, whether the action of the water has contributed to give that general form (according to the aqueous theory), or that the course of the water is a consequence of the form of the system itself. It was, therefore, very natural again, in devising a system of mountain defence, to take the course of the waters as a guide, as those courses form a natural series of levels, from which we can obtain both the general height and the general profile of the mountain, while the valleys formed by the streams present also the best means of access to the heights, because so much of the effect of the erosive and alluvial action of the water is permanent, that the inequalities of the slopes of the mountain are smoothed down by it to one regular slope. Hence, therefore, the idea of mountain defence would assume that, when a mountain ran about parallel with the front to be defended, it was to be regarded as a great obstacle to approach, as a kind of rampart, the gates of which were formed by the valleys. The real defence was then to be made on the crest of this rampart, (that is, on the edge of the plateau which crowned the mountain) and cut the valleys transversely. If the line of the principal mountain-chain formed somewhat of a right angle with the front of defence, then one of the principal branches would be selected to be used instead; thus the line chosen would be parallel to one of the principal valleys, and run up to the principal ridge, which might be regarded as the extremity.
We have noticed this scheme for mountain defence founded on the geological structure of the earth, because it really presented itself in theory for some time, and in the so-called “theory of ground” the laws of the process of aqueous action have been mixed up with the conduct of war.
But all this is so full of false hypotheses and incorrect substitutions, that when these are abstracted, nothing in reality remains to serve as the basis of any kind of a system.
The principal ridges of real mountains are far too impracticable and inhospitable to place large masses of troops upon them; it is often the same with the adjacent ridges, they are often too short and irregular. Plateaux do not exist on all mountain ridges, and where they are to be found they are mostly narrow, and therefore unfit to accommodate many troops; indeed, there are few mountains which, closely examined, will be found surmounted by an uninterrupted ridge, or which have their sides at such an angle that they form in some measure practicable slopes, or, at least, a succession of terraces. The principal ridge winds, bends, and splits itself; immense branches launch into the adjacent country in curved lines, and lift themselves often just at their termination to a greater height than the main ridge itself; promontories then join on, and form deep valleys which do not correspond with the general system. Thus it is that, when several lines of mountains cross each other, or at those points from which they branch out, the conception of a small band or belt is completely at an end, and gives place to mountain and water lines radiating from a centre in the form of a star.
From this it follows, and it will strike those who have examined mountain-masses in this manner the more forcibly, that the idea of a systematic disposition is out of the question, and that to adhere to such an idea as a fundamental principle for our measures would be wholly impracticable. There is still one important point to notice belonging to the province of practical application.
If we look closely at mountain warfare in its tactical aspects, it is evident that these are of two principal kinds, the first of which is the defence of steep slopes, the second is that of narrow valleys. Now this last, which is often, indeed almost generally, highly favourable to the action of the defence, is not very compatible with the disposition on the principal ridge, for the occupation of the valley itself is often required and that at its outer extremity nearest to the open country, not at its commencement, because there its sides are steeper. Besides, this defence of valleys offers a means of defending mountainous districts, even when the ridge itself affords no position which can be occupied; the rôle which it performs is, therefore, generally greater in proportion as the masses of the mountains are higher and more inaccessible.
The result of all these considerations is, that we must entirely give up the idea of a defensible line more or less regular, and coincident with one of the geological lines, and must look upon a mountain range as merely a surface intersected and broken with inequalities and obstacles strewed over it in the most diversified manner, the features of which we must try to make the best use of which circumstances permit; that therefore, although a knowledge of the geological features of the ground is indispensable to a clear conception of the form of mountain masses, it is of little value in the organisation of defensive measures.
Neither in the war of the Austrian Succession, nor in the Seven Years’ War, nor in those of the French Revolution, do we find military dispositions which comprehended a whole mountain system, and in which the defence was systematised in accordance with the leading features of that system. Nowhere do we find armies on the principal ridges always in position on the slopes. Sometimes at a greater, sometimes at a lower elevation; sometimes in one direction, sometimes in another; parallel, at right angles, and obliquely; with and against the watercourse; in lofty mountains, such as the Alps, frequently extended along the valleys; amongst mountains of a inferior class, like the Sudetics (and this is the strangest anomaly), at the middle of the declivity, as it sloped towards the defender, therefore with the principal ridge in front, like the position in which Frederick the Great, in 1762, covered the siege of Schwednitz, with the “hohe Eule” before the front of his camp.
The celebrated positions, Schmotseifen and Landshut, in the Seven Years’ War, are for the most part in the bottoms of valleys. It is the same with the position of Feldkirch, in the Vorarlsberg. In the campaigns of 1799 and 1800, the chief posts, both of the French and Austrians, were always quite in the valleys, not merely across them so as to close them, but also parallel with them, whilst the ridges were either not occupied at all, or merely by a few single posts.
The crests of the higher Alps in particular are so difficult of access, and afford so little space for the accommodation of troops, that it would be impossible to place any considerable bodies of men there. Now if we must positively have armies in mountains to keep possession of them, there is nothing to be done but to place them in the valleys. At first sight this appears erroneous, because, in accordance with the prevalent theoretical ideas, it will be said, the heights command the valleys. But that is really not the case. Mountain ridges are only accessible by a few paths and rude tracks, with a few exceptions only passable for infantry, whilst the carriage roads are in the valleys. The enemy can only appear there at certain points with infantry; but in these mountain masses the distances are too great for any effective fire of small arms, and therefore a position in the valleys is less dangerous than it appears. At the same time, the valley defence is exposed to another great danger, that of being cut off. The enemy can, it is true, only descend into the valley with infantry, at certain points, slowly and with great exertion; he cannot, therefore, take us by surprise; but none of the positions we have in the valley defend the outlets of such paths into the valley. The enemy can, therefore, bring down large masses gradually, then spread out, and burst through the thin and from that moment weak line, which, perhaps, has nothing more for its protection than the rocky bed of a shallow mountain-stream. But now retreat, which must always be made piecemeal in a valley, until the outlet from the mountains is reached, is impossible for many parts of the line of troops; and that was the reason that the Austrians in Switzerland almost always lost a third, or a half of their troops taken prisoners.—
Now a few words on the usual way of dividing troops in such a method of defence.
Each of the subordinate positions is in relation with a position taken up by the principal body of troops, more or less in the centre of the whole line, on the principal road of approach. From this central position, other corps are detached right and left to occupy the most important points of approach, and thus the whole is disposed in a line, as it were, of three, four, five, six posts, &c. How far this fractioning and extension of the line shall be carried, must depend on the requirements of each individual case. An extent of a couple of marches, that is, six to eight miles is of moderate length, and we have seen it carried as far as twenty or thirty miles.
Between each of these separate posts, which are one or two leagues from each other, there will probably be some approaches of inferior importance, to which afterwards attention must be directed. Some very good posts for a couple of battalions each are selected, which form a good connection between the chief posts, and they are occupied. It is easy to see that the distribution of the force may be carried still further, and go down to posts occupied only by single companies and squadrons; and this has often happened. There are, therefore, in this no general limits to the extent of fractioning. On the other hand, the strength of each post must depend on the strength of the whole; and therefore we can say nothing as to the possible or natural degree which should be observed with regard to the strength of the principal posts. We shall only append, as a guide, some maxims which are drawn from experience and the nature of the case.
1. The more lofty and inaccessible the mountains are, so much the further this separation of divisions of the force not only may be, but also must be, carried; for the less any portion of a country can be kept secure by combinations dependent on the movement of troops, so much the more must the security be obtained by direct covering. The defence of the Alps requires a much greater division of force, and therefore approaches nearer to the cordon system, than the defence of the Vosges or the Giant mountains.
2. Hitherto, wherever defence of mountains has taken place, such a division of the force employed has been made that the chief posts have generally consisted of only one line of infantry, and in a second line, some squadrons of cavalry; at all events, only the chief post established in the centre has perhaps had some battalions in a second line.
3. A strategic reserve, to reinforce any point attacked, has very seldom been kept in rear, because the extension of front made the line feel too weak already in all parts. On this account the support which a post attacked has received, has generally been furnished from other posts in the line not themselves attacked.
4. Even when the division of the forces has been relatively moderate, and the strength of each single post considerable, the principal resistance has been always confined to a local defence; and if once the enemy succeeded in wresting a post, it has been impossible to recover it by any supports afterwards arriving.
How much, according to this, may be expected from mountain defence, in what cases this means may be used, how far we can and may go in the extension and fractioning of the forces—these are all questions which theory must leave to the tact of the general. It is enough if it tells him what these means really are, and what rôle they can perform in the active operations of the army.
A general who allows himself to be beaten in an extended mountain position deserves to be brought before a court martial.