CHAPTER XII - Defensive
Position
Every position in which we accept battle, at the
same time making use of the ground as a means of protection, is a defensive
position, and it makes no difference in this respect whether we act more
passively or more offensively in the action. This follows from the general view
of the defensive which we have given.
Now we may also apply the term to every position
in which an army whilst marching to encounter the enemy would certainly accept
battle if the latter sought for it. In point of fact, most battles take place
in this way, and in all the middle ages no other was ever thought of. That is,
however, not the kind of position of which we are now speaking; by far the
greater number of positions are of this kind, and the conception of a position
in contradistinction to a camp taken up on the march would suffice for that. A
position which is specially called a defensive position must therefore have
some other distinguishing characteristics.
In the decisions which take place in an ordinary
position, the idea of time evidently predominates; the armies march against
each other in order to come to an engagement: the place is a subordinate point,
all that is required from it is that it should not be unsuitable. But in a real
defensive position the idea of place predominates; the decision is to be
realised on this spot, or rather, chiefly through this spot. That is the only
kind of position we have here in view.
Now the connection of place is a double one; that
is, in the first instance, inasmuch as a force posted at this point exercises a
certain influence upon the war in general; and next, inasmuch as the local
features of the ground contribute to the strength of the army and afford
protection: in a word, a strategic and a tactical connection.
Strictly speaking, the term defensive position has
its origin only in connection with tactics, for its connection with strategy,
namely, that an army posted at this point by its presence serves to defend the
country, will also suit the case of an army acting offensively.
The strategic effect to be derived from a position
cannot be shown completely until hereafter, when we discuss the defence of a
theatre of war; we shall therefore only consider it here as far as can be done
at present, and for that end we must examine more closely the nature of two
ideas which have a similarity and are often mistaken for one another, that is,
the turning a position, and the passing by it.
The turning a position relates to its front, and
is done either by an attack upon the side of the position or on its rear, or by
acting against its lines of retreat and communication.
The first of these, that is, an attack on flank or
rear is tactical in its nature. In our days in which the mobility of troops is
so great, and all plans of battles have more or less in view the turning or
enveloping the enemy, every position must accordingly be adapted to meet such
measures, and one to deserve the name of strong must, with a strong front,
allow at least of good combinations for battle on the sides and rear as well,
in case of their being menaced. In this way a position will not become
untenable by the enemy turning it with a view to an attack on the flank or
rear, as the battle which then takes place was provided for in the choice of the
position, and should ensure the defender all the advantages which he could
expect from this position generally.
If the position is turned by the enemy with a view
to acting against the lines of retreat and communication, this is a strategic
relation, and the question is how long the position can be maintained, and
whether we cannot outbid the enemy by a scheme like his own, both these
questions depend on the situation of the point (strategically), that is,
chiefly on the relations of the lines of communication of both combatants. A
good position should secure to the army on the defensive the advantage in this
point. In any case the position will not be rendered of no effect in this way,
as the enemy is neutralised by the position when he is occupied by it in the
manner supposed.
But if the assailant, without troubling himself
about the existence of the army awaiting his attack in a defensive position,
advances with his main body by another line in pursuit of his object, then he
passes by the position; and if he can do this with impunity, and really does
it, he will immediately enforce the abandonment of the position, consequently
put an end to its usefulness.
There is hardly any position in the world which,
in the simple sense of the words, cannot be passed by, for cases such as the
isthmus of Perekop are so rare that they are hardly worth attention. The
impossibility of passing by must therefore be understood as merely applying to
the disadvantages in which the assailant would become involved if he set about
such an operation. We shall have a more fitting opportunity to state these
disadvantages in the twenty-seventh chapter; whether small or great, in every
case they are the equivalent of the tactical effect which the position is
capable of producing but which has not been realised, and in common with it
constitute the object of the position.
From the preceding observations, therefore, two
strategic properties of the defensive position have resulted:
1. That it cannot be passed round.
2. That in the struggle for the lines of
communication it gives the defender advantages.
Here we have to add two other strategic
properties, namely—
3. That the relation of the lines of communication
may also have a favourable influence on the form of combat; and
4. That the general influence of the country is
advantageous.
For the relation of the lines of communication has
an influence not only upon the possibility or impossibility of passing by a
position or of cutting off the enemy’s supplies, but also on the whole course
of the battle. An oblique line of retreat facilitates a tactical turning
movement on the part of the assailant, and paralyses our own tactical movements
during the battle. But an oblique position in relation to the lines of
communication is often not the fault of tactics but a consequence of a
defective strategic point; it is, for example, not to be avoided when the road
changes direction in the vicinity of the position (Borodino, 1812); the
assailant is then in such a position that he can turn our line without
deviating from, his own perpendicular disposition.
Further, the aggressor has much greater freedom
for tactical movement if he commands several roads for his retreat whilst we
are limited to one. In such cases the tactical skill of the defensive will be
exerted in vain to overcome the disadvantageous influence resulting from the
strategic relations.
Lastly as regards the fourth point, such a
disadvantageous general influence may predominate in the other characteristics
of ground, that the most careful choice, and the best use of tactical means,
can do nothing to combat them. Under such circumstances the chief points are as
follows:
1. The defensive must particularly seek for the
advantage of being able to overlook his adversary, so that he may be able
swiftly to throw himself upon him inside the limits of his position. It is only
when the local difficulties of approach combine with these two conditions that
the ground is really favourable to the defensive.
On the other hand, those points which are under
the influence of commanding ground are disadvantageous to him; also most
positions in mountains (of which we shall speak more particularly in the
chapters on mountain warfare). Further, positions which rest one flank on
mountains, for such a position certainly makes the passing by more difficult,
but facilitates a turning movement. Of the same kind are all positions which
have a mountain immediately in their front, and generally all those which bear
relation to the description of ground above specified.
As an example of the opposite of these
disadvantageous properties, we shall only instance the case of a position which
has a mountain in rear; from this so many advantages result that it may be
assumed in general to be one of the most favourable of all positions for the
defensive.
2. A country may correspond more or less to the
character and composition of an army. A very numerous cavalry is a proper
reason for seeking an open country. Want of this arm, perhaps also of
artillery, while we have at command a courageous infantry inured to war, and
acquainted with the country, make it advisable to take advantage of a
difficult, close country.
We do not here enter into particulars respecting
the tactical relation which the local features of a defensive position bear to
the force which is to occupy it. We only speak of the total result, as that
only is a strategic quantity.
Undoubtedly a position in which an army is to
await the full force of the hostile attack, should give the troops such an
important advantage of ground as may be considered a multiplier of its force.
Where nature does much, but not to the full as much as we want, the art of
entrenchment comes to our help. In this way it happens not unfrequently that
some parts become unassailable, and not unusually the whole is made so: plainly
in this last case, the whole nature of the measure is changed. It is then no
longer a battle under advantageous conditions which we seek, and in this battle
the issue of the campaign, but an issue without a battle. Whilst we occupy with
our force an unassailable position, we directly refuse the battle, and oblige
our enemy to seek for a solution in some other way.
We must, therefore, completely separate these two
cases, and shall speak of the latter in the following chapter, under the title
of a strong position.
But the defensive position with which we have now
to do is nothing more than a field of battle with the addition of advantages in
our favour; and that it should become a field of battle, the advantages in our
favour must not be too great. But now what degree of strength may such a
position have? Plainly more in proportion as our enemy is more determined on
the attack, and that depends on the nature of the individual case. Opposed to a
Buonaparte, we may and should withdraw behind stronger ramparts than before a
Daun or a Schwartzenburg.
If certain portions of a position are
unattackable, say the front, then that is to be taken as a separate factor of
its whole strength, for the forces not required at that point are available for
employment elsewhere; but we must not omit to observe that whilst the enemy is
kept completely off such impregnable points, the form of his attack assumes
quite a different character, and we must ascertain, in the first instance, how
this alteration will suit our situation.
For instance, to take up a position, as has often
been done, so close behind a great river that it is to be looked upon as
covering the front, is nothing else but to make the river a point of support
for the right or left flank; for the enemy is naturally obliged to cross
further to the right or left, and cannot attack without changing his front: the
chief question, therefore, is what advantages or disadvantages does that bring
to us?
According to our opinion, a defensive position
will come the nearer to the true ideal of such a position the more its strength
is hid from observation, and the more it is favourable to our surprising the
enemy by our combinations in the battle. Just as we advisably endeavour to
conceal from the enemy the whole strength of our forces and our real
intentions, so in the same way we should seek to conceal from the enemy the
advantages which we expect to derive from the form of the ground. This of
course can only be done to a certain degree, and requires, perhaps, a peculiar
mode of proceeding, hitherto but little attempted.
The vicinity of a considerable fortress, in
whatever direction it may be, confers on every position a great advantage over
the enemy in the movement and use of the forces belonging to it. By suitable
field-works, the want of natural strength at particular points may be remedied,
and in that manner the great features of the battle may be settled beforehand
at will; these are the means of strengthening by art; if with these we combine
a good selection of those natural obstacles of ground which impede the
effective action of the enemy’s forces without making action absolutely
impossible, if we turn to the best account the advantage we have over the enemy
in knowing the ground, which he does not, so that we succeed in concealing our
movements better than he does his, and that we have a general superiority over
him in unexpected movements in the course of the battle, then from these
advantages united, there may result in our favour an overpowering and decisive
influence in connection with the ground, under the power of which the enemy
will succumb, without knowing the real cause of his defeat. This is what we
understand under defensive position, and we consider it one of the greatest
advantages of defensive war.
Leaving out of consideration particular
circumstances, we may assume that an undulating, not too well, but still not
too little, cultivated country affords the most positions of this kind.
CHAPTER XIII - Strong Positions
and Entrenched Camps
We have said in the preceding chapter that a
position so strong through nature, assisted by art, that it is unassailable,
does not come under the meaning of an advantageous field of battle, but belongs
to a peculiar class of things. We shall in this chapter take a review of what
constitutes the nature of this peculiarity, and on account of the analogy
between such positions and fortresses, call them strong positions.
Merely by entrenchments alone they can hardly be
formed, except as entrenched camps resting on fortresses; but still less are
they to be found ready formed entirely by natural obstacles. Art usually lends
a hand to assist nature, and therefore they are frequently designated as
entrenched camps or positions. At the same time, that term may really be
applied to any position strengthened more or less by field works, which need
have nothing in common with the nature of the position we are now considering.
The object of a strong position is to make the
force there stationed in point of fact unattackable, and by that means, either
really to cover a certain space directly, or only the troops which occupy that
space in order then, through them, in another way to effect the covering of the
country indirectly. The first was the signification of the lines of former
times, for instance, those on the French frontier; the latter, is that of
entrenched camps laid out near fortresses, and showing a front in every
direction.
If, for instance, the front of a position is so
strong by works and hindrances to approach that an attack is impossible, then
the enemy is compelled to turn it, to make his attack on a side of it or in
rear. Now to prevent this being easily done, points d’appui were sought for
these lines, which should give them a certain degree of support on the side,
such as the Rhine and the Vosges give the lines in Alsace. The longer the front
of such a line the more easily it can be protected from being turned, because
every movement to turn it is attended with danger to the side attempting the
movement, the danger increasing in proportion as the required movement causes a
greater deviation from the normal direction of the attacking force. Therefore,
a considerable length of front, which can be made unassailable, and good
flank-supports, ensure the possibility of protecting a large space of territory
directly from hostile invasion: at least, that was the view in which works of
this class originated; that was the object of the lines in Alsace, with their
right flank on the Rhine and the left on the Vosges; and the lines in Flanders,
fifteen miles long, resting their right on the Scheldt and the fortress of
Tournay, their left on the sea.
But when we have not the advantages of such a long
well-defended front, and good flank-supports, if the country is to be held
generally by a force well entrenched, then that force (and its position) must
be protected against being turned by such an arrangement that it can show a
front in every direction. But then the idea of a thoroughly covered tract of
country vanishes, for such a position is only strategically a point which
covers the force occupying it, and thus secures to that force the power of
keeping the field, that is to say, maintaining itself in the country. Such a
camp cannot be turned, that is, cannot be attacked in flank or rear by reason
of those parts being weaker than its front, for it can show front in all
directions, and is equally strong everywhere. But such a camp can be passed by,
and that much easier than a fortified line, because its extent amounts to
nothing.
Entrenched camps connected with fortresses are in
reality of this second kind, for the object of them is to protect the troops
assembled in them; but their further strategic meaning, that is, the
application of this protected force, is somewhat different from that of other
fortified camps.
Having given this explanation of the origin of
these three different defensive means, we shall now proceed to consider the
value of each of them separately, under the heads of strong lines, strong
positions, and entrenched camps resting on fortresses.
1. Lines.—They are the worst kind of cordon war:
the obstacle which they present to the aggressor is of no value at all unless
they are defended by a powerful fire; in themselves they are simply worthless.
But now the extent to which an army can furnish an effective fire is generally
very small in proportion to the extent of country to be defended; the lines
can, therefore, only be short, and consequently cover only a small extent of
country, or the army will not be able really to defend the lines at all points.
In consequence of this, the idea was started of not occupying all points in the
line, but only watching them, and defending them by means of strong reserves,
in the same way as a small river may be defended; but this procedure is in
opposition to the nature of the means. If the natural obstacles of the ground
are so great that such a method of defence could be applied, then the
entrenchments were needless, and entail danger, for that method of defence is
not local, and entrenchments are only suited to a strictly local defence; but
if the entrenchments themselves are to be considered the chief impediments to
approach, then we may easily conceive that an undefended line will not have
much to say as an obstacle to approach. What is a twelve or fifteen feet ditch,
and a rampart ten or twelve feet high, against the united efforts of many
thousands, if these efforts are not hindered by the fire of an enemy? The
consequence, therefore, is, that if such lines are short and tolerably well
defended by troops, they can be turned; but if they are extensive, and not
sufficiently occupied, they can be attacked in front, and taken without much
difficulty.
Now as lines of this description tie the troops
down to a local defence, and take away from them all mobility, they are a bad
and senseless means to use against an enterprising enemy. If we find them long
retained in modern wars in spite of these objections, the cause lies entirely
in the low degree of energy impressed on the conduct of war, one consequence of
which was, that seeming difficulties often effected quite as much as real ones.
Besides, in most campaigns these lines were used merely for a secondary defence
against irregular incursions; if they have been found not wholly inefficacious
for that purpose, we must only keep in view, at the same time, how much more
usefully the troops required for their defence might have been employed at
other points. In the latest wars such lines have been out of the question,
neither do we find any trace of them; and it is doubtful if they will ever
re-appear.
2. Positions.—The defence of a tract of country
continues (as we shall show more plainly in the 27th chapter) as long as the
force designated for it maintains itself there, and only ceases if that force
removes and abandons it.
If a force is to maintain itself in any district
of country which is attacked by very superior forces, the means of protecting
this force against the power of the sword by a position which is unassailable
is a first consideration.
Now such a position, as before said, must be able
to show a front in all directions; and in conformity with the usual extent of
tactical positions, if the force is not very large (and a large force would be
contrary to the nature of the supposed case) it would take up a very small
space, which, in the course of the combat, would be exposed to so many
disadvantages that, even if strengthened in every possible way by
entrenchments, we could hardly expect to make a successful defence. Such a
camp, showing front in every direction, must therefore necessarily have an
extent of sides proportionably great; but these sides must likewise be as good
as unassailable; to give this requisite strength, notwithstanding the required
extension, is not within the compass of the art of field fortification; it is
therefore a fundamental condition that such a camp must derive part of its
strength from natural impediments of ground which render many places impassable
and others difficult to pass. In order, therefore, to be able to apply this
defensive means, it is necessary to find such a spot, and when that is wanting,
the object cannot be attained merely by field works. These considerations
relate more immediately to tactical results in order that we may first
establish the existence of this strategic means; we mention as examples for
illustration, Pirna, Bunzelwitz, Colberg, Torres Vedras, and Drissa. Now, as
respects the strategic properties and effects. The first condition is naturally
that the force which occupies this camp shall have its subsistence secured for
some time, that is, for as long as we think the camp will be required, and this
is only possible when the position has behind it a port, like Colberg and
Torres Vedras, or stands in connection with a fortress like Bunzelwitz and
Pirna, or has large depôts within itself or in the immediate vicinity, like
Drissa.
It is only in the first case that the provisioning
can be ensured for any time we please; in the second and third cases, it can
only be so for a more or less limited time, so that in this point there is
always danger. From this appears how the difficulty of subsistence debars the
use of many strong points which otherwise would be suitable for entrenched
positions, and, therefore, makes those that are eligible scarce.
In order to ascertain the eligibility of a
position of this description, its advantages and defects, we must ask ourselves
what the aggressor can do against it.
a. The assailant can pass by this strong position,
pursue his enterprise, and watch the position with a greater or less force.
We must here make a distinction between the cases
of a position which is occupied by the main body, and one only occupied by an
inferior force.
In the first case the passing by the position can
only benefit the assailant, if, besides the principal force of the defendant,
there is also some other attainable and decisive object of attack, as, for
instance, the capture of a fortress or a capital city, etc. But even if there is
such an object, he can only follow it if the strength of his base and the
direction of his lines of communication are such that he has no cause to fear
operations against his strategic flanks.
The conclusions to be drawn from this with respect
to the admissibility and eligibility of a strong position for the main body of
the defender’s army are, that it is only an advisable position when either the
possibility of operating against the strategic flank of the aggressor is so
decisive that we may be sure beforehand of being able in that way to keep him
at a point where his army can effect nothing, or in a case where there is no
object attainable by the aggressor for which the defence need be uneasy. If
there is such an object, and the strategic flank of the assailant cannot be
seriously menaced, then such position should not be taken up, or if it is it
should only be as a feint to see whether the assailant can be imposed upon
respecting its value; this is always attended with the danger, in case of
failure, of being too late to reach the point which is threatened.
If the strong position is only held by an inferior
force, then the aggressor can never be at a loss for a further object of
attack, because he has it in the main body itself of the enemy’s army; in this
case, therefore, the value of the position is entirely limited to the means
which it affords of operating against the enemy’s strategic flank, and depends
upon that condition.
b. If the assailant does not venture to pass by a
position, he can invest it and reduce it by famine. But this supposes two
conditions beforehand: first, that the position is not open in rear, and
secondly, that the assailant is sufficiently strong to be able to make such an
investment. If these two conditions are united then the assailant’s army
certainly would be neutralised for a time by this strong position, but at the
same time, the defensive pays the price of this advantage by a loss of his
defensive force.
From this, therefore, we deduce that the
occupation of such a strong position with the main body is a measure only to be
taken,—
aa. When the rear is perfectly safe (Torres
Vedras).
bb. When we foresee that the enemy’s force is not
strong enough formally to invest us in our camp. Should the enemy attempt the
investment with insufficient means, then we should be able to sally out of the
camp and beat him in detail.
cc. When we can count upon relief like the Saxons
at Pirna, 1756, and as took place in the main at Prague, because Prague could
only be regarded as an entrenched camp in which Prince Charles would not have
allowed himself to be shut up if he had not known that the Moravian army could
liberate him.
One of these three conditions is therefore
absolutely necessary to justify the choice of a strong position for the main
body of an army; at the same time we must add that the two last are bordering
on a great danger for the defensive.
But if it is a question of exposing an inferior
corps to the risk of being sacrificed for the benefit of the whole, then these
conditions disappear, and the only point to decide is whether by such a
sacrifice a greater evil may be avoided. This will seldom happen; at the same
time it is certainly not inconceivable. The entrenched camp at Pirna prevented
Frederick the Great from attacking Bohemia, as he would have done, in the year
1756. The Austrians were at that time so little prepared, that the loss of that
kingdom appears beyond doubt; and perhaps, a greater loss of men would have
been connected with it than the 17,000 allied troops who capitulated in the
Pirna camp.
c. If none of those possibilities specified under
a and b are in favour of the aggressor; if, therefore, the conditions which we
have there laid down for the defensive are fulfilled, then there remains
certainly nothing to be done by the assailant but to fix himself before the
position, like a setter before a covey of birds, to spread himself, perhaps, as
much as possible by detachments over the country, and contenting himself with
these small and indecisive advantages to leave the real decision as to the
possession of territory to the future. In this case the position has fulfilled
its object.
3. Entrenched camps near fortresses.—They belong,
as already said, to the class of entrenched positions generally, in so far, as they
have for their object to cover not a tract of territory, but an armed force
against a hostile attack, and only differ in reality from the other in this,
that with the fortress they make up an inseparable whole, by which they
naturally acquire much greater strength.
But there follows further from the above the
undermentioned special points.
a. That they may also have the particular object
of rendering the siege of the fortress either impossible or extremely
difficult. This object may be worth a great sacrifice of troops if the place is
a port which cannot be blockaded, but in any other case we have to take care
lest the place is one which may be reduced by hunger so soon that the sacrifice
of any considerable number of troops is not justifiable.
b. Entrenched camps can be formed near fortresses
for smaller bodies of troops than those in the open field. Four or five
thousand men may be invincible under the walls of a fortress, when, on the
contrary, in the strongest camp in the world, formed in the open field, they
would be lost.
c. They may be used for the assembly and
organisation of forces which have still too little solidity to be trusted in
contact with the enemy, without the support afforded by the works of the place,
as for example, recruits, militia, national levies, etc.
They might, therefore, be recommended as a very
useful measure, in many ways, if they had not the immense disadvantage of
injuring the fortress, more or less, when they cannot be occupied; and to
provide the fortress always with a garrison, in some measure sufficient to
occupy the camp also, would be much too onerous a condition.
We are, therefore, very much inclined to consider
them only advisable for places on a sea coast, and as more injurious than
useful in all other cases.
If, in conclusion, we should summarise our opinion
in a general view, then strong and entrenched positions are—
1. The more requisite the smaller the country, the
less the space afforded for a retreat.
2. The less dangerous the more surely we can reckon
on succouring or relieving them by other forces, or by the inclemency of
season, or by a rising of the nation, or by want, &c.
3. The more efficacious, the weaker the elementary
force of the enemy’s attack.
