If the situation is to be cleared up by fighting, fire action must be employed, and as soon as this occurs, whether on the part of the enemy or oneself, a gradual employment of force is not only no disadvantage, but is demanded by the circumstances. For at first the fight must be carried out from depth; the Napoleonic "Je m'engage et puis je vois"[32] holds good; one's own main force will only be engaged when the strength and intentions of the enemy become in some measure known. It will, however, be advisable in all cases to keep a strong reserve in hand until prepared to advance to a well-considered and planned attack.
The passage of defiles, also, is scarcely likely to be undertaken in serious war in the manner so often seen at manœuvres. Here the chief matter for consideration is generally to keep one side as far from the defile as possible, in order that the passage of the other may be possible. Such tender solicitude is scarcely to be expected of a real enemy, and it will, I opine, scarcely occur to anybody in war to attempt a defile without preparation, and to advance on the farther side against an enemy whose strength, as is generally the case in war, is unknown, thereby running the danger of being thrown back on the defile and of suffering enormous loss. Such a danger, to which the whole force is exposed, would certainly only be incurred when the gravest necessity compelled. What the Regulations say in this respect (434)[33] has, to my mind, but a limited practical significance.
Such directions would only be followed if the enemy were known to be still far distant and approaching, where there is time and space sufficient, and where the force is considered to be at least a match for the enemy. Even then, preparations should be made for a possible retirement. In all other cases, however, a defile on the far side of which the enemy is supposed to be will only be crossed when the ground for deployment on the far side is at least commanded with fire in such a way that the enemy will not be able, in case a retirement becomes necessary, to pursue right into the defile.
It will therefore generally be advisable to throw forward a few squadrons at a rapid pace across the defile in order to occupy with dismounted action strong points on the far side, from which the foreground can be covered. This will secure the passage of the main body and arrest any possible pursuit. It will often be advantageous to provide such squadrons with machine-guns. Artillery can most suitably come into action on the near side of the defile, so that it may be able to cover the country on the far side with its fire.
Even if a defile occupied by the enemy has been captured by fire action it is advisable, before the main body crosses it, to secure a few strong points in the foreground, in order to secure the passage against counter-attack by the enemy's reserve.
Such necessary care in the preliminaries of an action, however, must in nowise lead commanders to allow themselves to be forced to adopt a defensive attitude or to abstain from decisive attack. That is not the intention. Such measures are only taken to clear up the situation, which cannot generally be done in war without fighting, and to diminish the risks of any further action which may ensue. If the enemy has so far shown himself that an appreciation can to some extent be arrived at as to its strength, if he has brought artillery into position, if perhaps he has attacked our advanced guard, or by the action of the latter has been forced to throw more men into the fight, if, in short, it can be determined that an attack has prospect of success, then the decisive offensive must be undertaken with all the force hitherto kept back. Detachments, also, which have been dismounted can then, according to circumstances, be withdrawn from the fire fight and otherwise used. The attack, especially when mounted, will usually be delivered with greatest advantage from the flank, and must, as a rule, reach well out in order to escape as far as possible the artillery and machine-gun fire of the enemy. Whether it be undertaken mounted or dismounted will depend upon the attitude of the enemy and the attendant circumstances. In either case it will be advisable to husband a reserve as long as possible to meet the vicissitudes of the fight, or to be used for a bold stroke, when it is seen where a decision may be arrived at.
If dismounted action must be undertaken, the principles which govern the infantry attack hold good. The fire of the artillery and, where possible, the machine-guns must naturally be utilised for the support of the attacking troops. The dispositions for the action should, however, never depend upon the possibility of finding a good artillery position. The artillery must suit itself to the circumstances, and come into action wherever it can best co-operate in carrying out the commander's intentions. It can often be profitably employed in the protection of an exposed flank. It will be of advantage to shelter it behind some obstacle in order to save the necessity of finding a detachment for its security. Machine-guns may sometimes be advantageously used for the protection of the artillery. It is at the same time advisable that a specially detailed cavalry escort should be dismounted for this object.
A concentration of the batteries facilitates fire command and measures for protection. A dispersion by groups allows a better effect against the hostile artillery and usually affords a more extensive field of fire. Machine-guns, which must generally look for positions as far to the front as possible, or, if they are protected, to a flank, will usually be best concentrated in a single fire position. They may, however, be disposed by sections when occasion demands. This principle holds good also for the artillery. Hard-and-fast rules must be avoided if the many and varied demands of a cavalry fight are to be met. The line of fire, however, of artillery and machine-guns should never be allowed to limit the movements of our own cavalry.
In consequence of the peculiar nature of the cavalry fight it will often be desirable to keep the limbers with the guns. It may also be an advantage not to bring the first-line transport and a portion of the wagons on to the field itself. For similar reasons the light ammunition columns will at the commencement probably march with the baggage. Thus too it will often be necessary for the machine-gun detachments to keep their teams near the guns, or to shoot from the carriage and to leave the ammunition wagons in a safe place. All these measures contain, however, the danger that ammunition may not be at hand when wanted, or that these indispensable supplies may fall into the hands of hostile raiding parties. The failure of ammunition may, especially in the case of a protracted dismounted action, be of decisive importance. Such will be especially the case where the ground favours the use of the rifle, or where the hostile cavalry is strengthened by cyclists or mounted infantry and shows an eagerness (natural under such circumstances) to take advantage of such methods of fighting.
The cavalry leader will, under these conditions, only undertake what must be an obstinate combat when he cannot in any way avoid it, or at least is not compelled to attack frontally. He will rather endeavour, if the general situation allows, to separate the hostile cavalry from the less mobile infantry by repeated turning movements and then to attack it when isolated. If the hostile cavalry and horse artillery can be driven from the field, the infantry detachments will form an easy prey for the artillery or can be surrounded. Under such circumstances, always with due regard to the general situation, the road on which the advance is being made may for a time be abandoned and the turning movement carried out with the whole force, if such a proceeding affords a favourable prospect of tactical success. Such a movement threatens the enemy's communications in the same way as it exposes our own. Victory, however, will secure the latter again, and will be the more decisive the farther the enemy can be driven from his natural line of retreat.