Front of Attack.The tactical unit for an attack is a division. A division that is placedin the front line for this purpose is called an attacking division. To such a division is assigned the task of attacking and capturing a definite length of front of the hostile position. All the necessary means to carry out this mission are in the hands of the division commander.
The tactical unit for anassault, in this division, is the battalion. Each assaulting battalion is placed in front of that part of the hostile line against which it is to operate, which is called its front of attack. The length of this front is variable with the tactical situation. Also, this length in no way indicates to the enemy the strength of the attacking troops because they are disposed for the attack in depth. According to the size of the front of attack, the battalion commander will place two or three companies in the assaulting column, and two or one company as reinforcing support.
Conditions of the Assault.An assaulting battalion must be disposed in a certain manner, which is called the assaulting disposition. In establishing this disposition, we must consider the distance of the assault and the outline of the assaulting lines.
Distance of the Assault.The distance over which the troops make their assaultacross “No Man’s Land” must not be too great. This is to avoid as much as possible the enemy’s barrage and machine gun fire. For this reason, parallels of departure or jumping-off trenches, if necessary, may be constructed out in front of the first line for the assembling of the assaulting troops. On the other hand, your own first line should not be so near to the enemy’s position as to be in the zone of artillery dispersion when your own batteries are firing at the enemy’s first line. However, one is not always master of this distance, as it is a result of long fighting and occupation of the two positions. The proper concealment of these attack works, such as the parallels of departure, is an essential condition of success.
The Trace of the Lines of Departure.The trace of the lines of departure must be parallel to the first line of the enemy, not to your own, so that the assaulting troops will simply have to start in a perpendicular direction from the lines of departure to reach their objective. In other words, the assault is a simple frontal attack without maneuvers.
Ground Preparation for the Assault.It follows from the statements of the conditions of the assault and also of the tactical and material preparation of the attack, that theterrain from which these troops will start must be specially organized for this purpose. We have discussed the principles and details of the organization of the position for the defense, and it is clear that these must differ materially from those for the attack. An attack, like a defense, is made with the units disposed in depth. To launch an attack, certain of the defensive works that play but a passive rôle in the resistance, such as barbed wire entanglements, must be rearranged, modified, or partially eliminated. Other elements, such as routes, boyaux, and supply depots that facilitate the forward movement of reinforcements, are multiplied.
Details of the Preparation of the Ground for the Attack.All the details of the preparation of the ground for the attack are laid down in an order called the “Plan of Ground Disposition” issued by the general of the attacking division. This order is divided into two parts: the organization of the works, and their execution.
Organization.We know that the disposition of an assaulting unit is in the form of successive echelons, called waves. In order to protect these waves before the assault, it is necessary to construct for them trenches parallel to the enemy’s first line; and for this reasonthese are called parallels of departure. The trace of the first parallel fixes the directions of the others behind. For example, an assaulting battalion which is going to advance in four waves, might have two parallels of departure with two waves in each parallel. These parallels are narrow trenches like the defensive lines, but with a series of steps in the front side so that the men can go over the top easily. If there are no steps, trench ladders or footholds must be used.
Theoretically, one might think that the distance between these successive parallels should be the same as that between the attacking lines. But this is not practicable. Such practice would mark out boldly on the ground, for the enemy’s air observation, your intentions and your dispositions for the attack. Therefore, this method is strictly prohibited. Besides, it is not necessary, since the regulation distances between the lines and waves are not realized from the point of departure of the assault. The object of the assaulting companies is to cross “No Man’s Land” as quickly as possible to avoid the enemy’s defensive barrage and machine gun fire. Consequently, when the different lines of the first wave jump out of the same parallel of departure, they will dash across to the enemy’s first line withlittle regard to distances but with a fixed idea of reaching their first objective before the hostile garrison, and before the enemy’s barrage intervenes. They attain their regulation distance as soon as the zone of barrage is passed and when they have arrived at and crossed the first hostile line.
In order not to print the attack on the ground, so to speak, these different parallels of departure are not constructed in front of your position unless absolutely necessary. They are constructed when the distance across “No Man’s Land” is more than five hundred yards, when there is natural cover, such as woods to conceal them, and sometimes on reverse slopes. The different defensive lines of the sector make very convenient parallels of departure. The first waves of the assaulting company are placed in the firing and cover trenches of the first line. The reinforcing platoons are disposed in the transversal and intermediate and support lines. Behind these lines are constructedplaces d’armesor assembling places for the reserve troops. Theseplaces d’armesconsist of a series of short transversal trenches leading off both sides of a central boyau.
If the first hostile line is too far from our own first line, on the night previous to theattack, hasty parallels of departure are constructed out in “No Man’s Land” for the leading wave of the assault. This is to give this leading element the best possible chance to arrive at the enemy’s first line uninterrupted by artillery fire and before the hostile garrison.
The work of preparing the ground for the disposition of the attacking troops also comprehends the following:
Several boyaux.
Command posts and observatories in advance of those of the defensive sector. Each chief must now be in the middle of his unit and not behind it.
Depots and medical aid stations. Each company has its own little ammunition depot near the post of the captain.
Ditches for telephone wires. Each battalion has telephone wires brought up in its main boyau as far as the first parallel. At this point, telephone material is stored so that the system can be carried into the enemy’s position with the least delay.
Small bridges are constructed for the passage of the parallels by the reserves.
It is not necessary that the shelter accommodations be numerous, especially in the first line, because the assaulting troops are brought in only a few days before the attack.
The Execution of the Works.The second part of the plan of ground disposition contains the details of the execution of the works for the preparation of the ground previous to the attack. This part consists of;
1. Emergency works (necessary to the assault).
Observatories and command posts.
The first two parallels of departure for each battalion. If none need be constructed, the defensive lines used for this purpose are designated.
Secondary boyaux between parallels, one for each company.
Entrance and evacuation boyaux.
Ammunition depots and water points.
Dressing stations.
If there is more time, the following are constructed:
The third and fourth parallels.
Telephone wires and material brought up.
Bridges for crossing the parallels.
2. Time of duration of the execution of the works.
This may vary from three to twelve days, or even more, depending upon circumstances.
3. Division of labor.
This depends upon the number of specialworking parties at your disposal. A whole division may be assigned for this work, but it is not the division that will make the attack.
4. Tools.
The tools required for this work are requisitioned from the headquarters of the attacking army.
5. Ammunition depots.
Cartridges, hand grenades, and signal rockets.
6. Ammunition depots.
Sandbags and logs.
7. Transportation of supplies.
Special means of transportation besides the usual ones, railroads, motor trucks, mules, horses, etc.
During the time employed in preparing the ground for the attack, the artillery executes the preliminary bombardment. This comprehends three kinds of fire.
1.Counter-Battery Fire.A certain part of the artillery is detailed to destroy the hostile batteries or, if this is not possible, to neutralize them. This result is obtained by methodical fire on precise targets. Eachbattery or group of batteries is assigned certain emplacements to destroy. Counter-battery fire is long-winded work and is begun several days or even weeks before the attack. If the hostile batteries are not destroyed before the time of attack, they must be neutralized at this moment by violent shelling by all the batteries disposed for this purpose, with shrapnel and other special shells. This counter-battery action will hinder the hostile artillery from executing defensive fire, barrage, preventive fire, counter-preparation fire. It is carried out by special groups of heavy and light artillery under control of the general.
2.Fire on Communication Routes, Depots, etc.This fire, besides its destructive effect upon the enemy’s position, hinders the arrival of reinforcing troops, material, ammunition, and food. The shelling of distant roads, depots, and bivouacs is carried out by batteries of long-range guns. The fire on the nearest communications, such as interior supply routes, entrances of boyaux, kitchen emplacements, etc., is executed by light batteries of the divisional artillery.
3.Destructive Fire.Before the attack, the whole of the enemy’s position is submitted to methodical and violent artillery fire for the purpose of destroying:
Obstacles which may hinder the advance of the assaulting column: accessory defenses, such as barbed wire entanglements.
Elements of the defense, such as strong points, machine gun emplacements, observatories, depots, shelters, and dugouts.
Each different kind of target calls for a certain number of rounds of a particular caliber. These calculations of the different numbers of rounds are the results of experience and are set down in tables for the information of the sector commander. The time, therefore, necessary for a proper preparation for the attack is a function of the number and strength of targets. The artillery preparation may last from one to twenty days, but it must continue until the elements of the hostile position are sufficiently destroyed to assure a successful attack.
Before an offensive, there is placed at the disposal of the attacking divisions, besides their regular divisional artillery, a special allotment of batteries. The different calibers of guns are used according to the nature of the target. The largest calibers are employed against the strongest elements of the organization: nests of resistance, strong points, and deep dugouts. Light artillery is used to obliterate trenches and boyaux and interior barbedwire entanglements. Trench mortars serve to destroy the elements of the first line and its accessory defenses.
Plan of Artillery Action.The details for the execution of these different artillery fires are laid down in the plan of action of the artillery of the army corps or of the division. This plan is a part of the plan of battle of the division. These details must be carried out punctually and with precision. The sector commanders are not interested directly in the execution of these fires, but they are in their results.
Duties of the Infantry during the Artillery Preparation.In connection with the artillery fire, the infantry in the position must observe the results of the bombardment and the leaders report their opinion upon its control.
Observation.The observation of the counter-battery fire, long-range fire on communication routes, and destructive fire on the interior of the position, falls upon the artillery’s ground observers and the aviation service. But the duty of observing the results of destructive fire on the enemy’s first line is carried out with the help of the infantry observers. Each regiment must observe the front upon which it is to make the attack.Special attention is paid to the destruction of barbed wire entanglements and machine gun emplacements. The interested infantry does not content itself with a passive observation, but must send out at night, or even in daylight, offensive reconnaissance parties. Their mission is to actually go into the enemy’s first line, to ascertain its condition, and to investigate the breaches in the hostile entanglements. The tactics of such a reconnaissance are the same as for a raid. The information gathered is sent to the division headquarters in the daily report of the intelligence officer or in special information reports.
Control.It is both the privilege and the duty of the infantry commanders to state in their daily reports their opinion on the artillery preparation. If they do not express their exact opinion on the progress of the bombardment, they are liable to pay for their carelessness at the time of the assault.
Destruction of the Enemy’s Position.The experiences of three years of trench warfare have given bitter proof that an attack against an insufficiently destroyed position will not only fail but will result in great losses. It is sheer folly to attempt an assault against undestroyed entanglements, or against a linein which the machine gun posts have not been demolished. One does not oppose materiel with men. In trench warfare, the conquest of the ground is made by the artillery; the infantry follow up this conquest to occupy and to hold the ground. The essential condition for the success of an attack depends upon the proper destruction of the elements of a position by the artillery.
Plan of Battle.The plan of battle depends upon, first, the strength of the enemy, obstacles to the attacking troops, lines of defense, nests of resistances, barbed wire, etc.; and secondly, the mission of the attacking unit and the means at its disposal.
Strength of the Enemy.The Information Service of a division has so many different methods of obtaining information and data of the enemy and his defenses that the assaulting troops can be constantly kept advised of the state of the hostile position. The regiment receives daily from the division headquarters an information bulletin, aëroplane pictures, and precise maps of the hostile lines. Upon these data the regimental commander bases his plan of battle. Comparisons of aëroplane pictures and maps are particularly useful. From all these data, the regimental intelligence officer makes pertinent extracts for the information of the battalion commander. Copies of the different maps are distributed by the battalion and company commanders to their officers and non-commissioned officers in order that they may have a better knowledge of the hostile position for the attack.
CONVERGENCE ON THE OBJECTIVE FOR THE ATTACK METHOD OF REDUCING A NEST OF RESISTANCE
Mission.The general plan of battle is issued by the division commander. Based upon the terms of this order, the Colonel, Battalion Commander, and Captain issue detailed orders of their own plan of battle. The plan of battle of a small unit usually comprehends the following points:
Mission of the unit in the attack.
Front to be attacked, with definite limits.
Objectives, different lines to be taken, the last objective.
Disposition of the unit for the attack; formation, intervals.
Disposition of the unit in the parallels of departure before the attack.
The day (D) and hour (H) of attack.
Direction of the attack; compass angle.
Position of the leader.
Tactical relation with the neighboring units during the advance.
Use of specialists; machine guns, trench cleaners, etc.
Support of artillery during the attack.
Unit liaison during the attack:
With neighboring units and leaders (runners, telephone, signaling, carrier pigeons).
With the support artillery (detachment of liaison, observatories, and rockets).
With air service (rockets, signaling, Bengal fires).
With balloon service (searchlights).
Equipment for the attack.
Supply of ammunition and water; advanced supply points.
Evacuation of the wounded; dressing stations, routes of evacuation, auto ambulance points. Also, routes of evacuation for prisoners and assembling points for same.
This plan of battle is so drawn up that it may be executed any later day that may be designated in the order for the attack.
Preparation of the Men for the Attack.The work of fitting their men physically, professionally, and morally for the task before them devolves upon the leaders of all ranks. By a system of relief, the men of the garrison get short periods of rest behind the sector to shake off the atmosphere of the trenches. Continuous instruction of both men and officers in the basic principles of fighting should be carried on at all times. The moral training of themen depends to a great extent upon the officers. The leaders, by example and encouraging words, should instill into their soldiers that fighting spirit which makes for success in battle.