AIR WARFARE. This article deals with the general prin ciples governing the employment of air forces in war, and with the effect of the advent of air power upon problems of the defence of the British empire. It does not enter into any details either of air fighting (for which see AIRCRAFT IN WAR) or of co-operation with a navy or an army (for which see AIR CO-OPERATION) .
With the possible exception of high mountain ranges, aircraft are not stopped by any ordinary obstacle, either natural or arti ficial. The stretches of sea or lines of fortresses that used to form the frontier defences of nations are barriers no longer. They are not tied down like an army by a line of communication from the fighting front to their base; they can go back to their aero dromes by an entirely different route from that by which they arrived. On the other hand, the time during which they can re main active i.e., in the air, is short, owing to the limitations of their fuel and ammunition capacity; they have no physical stop ping power, such as is afforded by barbed wire or bayonets and they are handicapped by certain weather conditions, especially fog and low clouds.
There is a prevalent idea that large aircraft are necessarily more effective fighting instruments than small aircraft, and that there is no inherent difficulty in constructing a battleship of the air. This idea is based upon the assumption that, as regards scalar effect, aircraft follow the same law as ships. This is so in the case of dirigibles, but there is a fundamental difference between ships and aeroplanes. Increasing the dimensions of a ship results in an increase in the ratio of useful load to total weight, hence in the case of warships it is possible, by increasing the total ton nage sufficiently to have a greater ratio available for engines, fuel armour and armament, and thus to get any desired combination of speed, endurance, protection and gun power. Increasing the dimensions of an aeroplane, at any rate with the present methods of construction, will increase the absolute load that can be carried but does not increase the ratio of useful load to total weight ; the ratio remains constant or even decreases with increase in size. Speed, rate of climb and handiness are of first importance in air fighting, and these can be obtained to a higher degree in small aeroplanes than in large. The fighting aeroplane of to-day is the comparatively small machine, generally with one occupant‘—some times with two—and not the big heavy weight-carrier.
It has sometimes been said that aircraft are wasteful in man power because it requires a large number of men to keep one aeroplane serviceable at the front. Actually, on the Western front in the war of 194-18, the numbers were less than those required for a field gun, but in any case the argument is wrong. We do not want to kill off our young men in war; we want to keep them for the peace which is beyond war. By the use of aircraft we are substituting machinery for flesh and blood; in stead of exposing one-third of our serving men to steel, lead and gas, we are exposing but one twenty-fifth. Provided we attain our end, the fewer men we expose to risk of wounds and death the better. War machinery of all kinds should not be regarded as wasting a large number of men in maintenance, but as effecting a vast economy in the utilization of available man power.
The means which a nation can now utilize in order to bring pressure to bear upon the enemy people, may be grouped roughly as f ollows (a) Moral (i) Propaganda; (ii) Dislocation of normal life. (b)* Economic; Stoppage of movement of goods.
(c) Physical (i) Deprivation of necessities; (ii) Injury to person or property; (iii) Loss of means of winning the war.
Many of these interact; for instance, stoppage of movement of goods may lead to deprivation of necessities which will in turn render the people more susceptible to moral effect. Again, the same stoppage will mean reduction of trade which may lead to a nation being unable to keep sufficient credits in foreign coun tries to purchase essential material for munitions. To deprive an enemy nation of the possibility of winning a war, part at any rate of the system by which it carries on that war must be de stroyed, viz.:—(i) The centre of government. (2) The navy, army and air forces. (3) Munition factories and transport sys tem. Let us now briefly consider what means each of the three fighting services utilize in order to bring pressure to bear upon the enemy nation.
A navy acts mainly by economic methods, through control of overseas communications; the result of this will not usually become apparent for a considerable time.
An army ultimately brings pressure to bear by occupation of the enemy's country but cannot do this until it has disposed of the enemy's army; as has already been stated, this is usually a slow and costly process both to life and property.
An air force acting separately can contribute its share of pres sure in several ways; by dislocation of the normal life of the people, by deprivation of supplies through attacks on transpor tation systems, by bombing the centre of government. Many of the objectives which an air force can attack at the beginning of a war, could, prior to the advent of aircraft, be reached only after prolonged fighting. This power of bringing direct pressure to bear upon its enemy from the start of the war, may be a deciding factor in reducing the time required to compel an oppo nent to come to terms.
Aircraft may be used for the observation of gunfire from battleships or to carry out photography prior to an attack by an army. These are examples of direct co-operation when air craft may be looked upon as an arm of the other two services. On the other hand, take the situation in 1917 when the Germans were sinking so many ships by unrestricted submarine warfare, that food and other supplies in Great Britain were getting peril ously short. Had the Germans had available at that time an efficient fleet of bombing aircraft the best way of utilizing them to increase the effect already being caused bv submarines. would not have been in direct co-operation with them by bombing Brit ish merchant ships at sea, but by attacking the port of London. This would not only have been within easier reach but would also have offered a more effective target. Again in June 1918, the Germans had advanced dangerously near Paris, and the moral of the French people was seriously affected. The most effective means of utilizing aircraft to increase the effect of the German army's success on the French people would not have been to bomb the French army entrenched on the flanks of the German salient but to attack Paris itself and its communications. These are examples of aircraft acting separately but in co-ordination with the action of a navy or an army. The nature of the objec tives of an air force acting separately will be decided by a gov ernment in accordance with its general policy for the conduct of the war.
Control of sea communication may be a vital matter, in which case a government might decide that the objectives were to be such as would best assist its navy to carry out this duty. To gain complete control necessitates destruction of the enemy's main fleet. Merely containing a fleet i.e., bottling it up in harbour, is not so effective as destruction. In the past the chief difficulty has not been so much in defeating the enemy fleet as in bring ing it to action; this mainly because a hostile fleet can avoid bat tle by taking refuge in a protected harbour. It is not impossible that by continuous attack with bombs and torpedoes, aircraft may in another war force an enemy fleet out of harbour, or else reduce it to impotence if it refuses to move. Or the objective might be the enemy centre of government, in which case attacks would be made on buildings housing his various ministries and on the com munication system. Again the duty assigned to an air force might be to bring about a continual dislocation of the normal life of the enemy people; and the objectives would then be centres of production, railways, docks and shipping or water and lighting systems.
How far air forces in another war will attack centres of popula tion with the deliberate intention of terrorizing the inhabitants is an open question. Such a method of conducting war is opposed to all instincts of chivalry. It will, after the war, react on the moral condition of the nation that started it and, to quote from an article by Marshal Foch:—"La guerre n'est pas le but su preme, car au-dessus d'elle y a la paix." On the other hand, it will usually be a very effective method of bringing pressure to bear. It was resorted to, although on a very small scale, in the World War; and when a nation's existence is at stake, it is un likely to be bound by any rules, but only by expediency. The conclusion to be reached is that such action is well within the bounds of possibility and therefore that every step must be taken to meet such action on the part of an enemy.
The situation of an air force is similar to that of a recon noitring party, though on a different scale. In a paragraph deal ing with the action of troops employed on reconnaissance it is laid down in the Army Field Service Regulations (August 1924) : "The enemy's advanced troops will be engaged only if the com mander considers this will be the best means of accomplishing his mission." This argument does not imply that an air force may expect to carry out its duties without fighting; it will have to fight, and fight hard to reach its objectives for attack. But it does imply this, that if its mission is to attack the enemy centre of government, it will not begin by concentrating all its efforts in an attempt, almost certainly a vain one, to destroy the enemy air force, for to do so would be to throw away one of the greatest assets of aircraft, the power to act simultaneously with the declaration of war. It will attack the enemy centre of govern ment at once, will make these attacks its main object and regard fighting in the air as a diversion, whatever the extent of the fighting may be. For continued attacks on one area will un doubtedly lead to fighting in the air, and the more localized the attacks the more intensive the fighting. This was what occurred in France in the World War. At that time the mission of the British air service was co-operation with the army. This co-opera tion took place mainly over a narrow belt in which the enemy fighters were certain to find our co-operation aircraft. To enable these to carry out their work a continuous offensive was carried out against the enemy fighting machines, but as was laid down at the time this offensive was not an end in itself, only the means by which the main mission assigned to the air service could be accomplished. Further, at no time could our air force be said to have obtained more than a local and temporary superiority; the enemy air force on the Western front could never be said to have been definitely defeated, yet in spite of this the army co-operation squadrons carried on with their work. Had they waited till vic tory in the air had been won, they would have made but little progress with their mission.
The mobility of aircraft is a great asset, and must be utilized to the full in order to concentrate effort on the decisive object. This mobility is not only a matter of moving quickly from one part of the world to another, but also of the power to use the same machines for many different purposes whether it be over the sea or over the land. The mobility and freedom of action of aircraft confer great potentialities for surprise which must be exploited to the utmost. These same assets may also tend to lead to a dis persal of any available force of aircraft ; this is wrong and must be guarded against ; concentration of effort is as essential in the air as on land or sea.
The extent to which aircraft can bomb battleships is still a subject of discussion, but there is no doubt that they are able to sink or disable merchant ships, either by bombs or torpedoes. Under the Washington Agreement, which has, however, never been ratified, it is laid down that merchant ships must be visited and searched before seizure, and further that they must not be destroyed unless adequate arrangements are made for the safety of the crews. At the present time this agreement is not held to apply to aircraft, but only to fighting ships. Should the agreement eventually be applied to aircraft it would be very difficult for them to act by themselves against merchant shipping, but, as stated above, when considering the bombing of centres of population we cannot be certain that our enemies in another war will comply with any agreement that may be made on the subject. In any case, in co-operation with warships aircraft will be of great value, both in scouting for merchant vessels and also in forcing them to heave to until one of their own warships can arrive. They will also possibly act effectively against forts and seriously hamper work in them. Aircraft must, therefore, be regarded as an added danger to overseas communications. On the other hand, experi ence in the War of 1914-1918 showed that aircraft were very valuable for anti-submarine defence and their mere presence with a convoy was nearly always sufficient to secure it against subma rine attack. In 1918 out of 7,000 convoys which had aircraft escort, only six were attacked by submarines.
All these difficulties are avoided by the use of aircraft. Acting from a secure base they can operate up to 200 miles or more without the need for any line of communications, other than that from their home country to their base, or for any troops to guard one. The nature of the country forms no obstacle to their move ment and their speed is far greater than anything the enemy can attempt. Provided, therefore, that the distances are not too great, aircraft are able to act within a few hours, whereas previously the preparations took weeks, or even months. This rapidity of action is an invaluable asset; any rising that takes place in un civilized countries is usually small and local in the first instance but if left unchecked will quickly spread. Aircraft can usually nip trouble in the bud. But the value of aircraft lies not only in carrying out tribal operations but in obviating their necessity. It must be remembered that a tribesman usually fights for two rea sons; firstly, he is poor and wants loot, secondly, he likes fighting for its own sake provided the odds are in his favour. Aircraft offer him neither of these two allurements. There is no line of communication to raid with the probability of obtaining boots and ammunition, no camps from which to steal camels and rifles, no pickets to be surprised and overwhelmed by superior num bers. All he can do is to fire away valuable ammunition at tar gets which, if hit, are seldom brought down and even then are useless to him. Again, in the control of a country, ground forces act mainly by occupation. This leads to the establishment of a large number of small posts which are often isolated and difficult to supply, reinforce or relieve. They form tempting objectives to unruly natives. On the other hand, when aircraft control a country there is no need for dispersion and isolation. Because of their potentiality for rapid action at a distance, they can be concentrated in one or two secure spots and still be able to deal with any disturbance in a few hours, either by taking a political officer to confer with the malcontents, by dropping leaflets, by demonstration flights or by actual attack.
In the future it will be necessary to prepare to face not spas modic attacks of this nature but determined and serious attacks and these, it must be remembered, will be delivered straight against the heart and brain of the empire and may in themselves form the declaration of war. London is badly situated for de fence against aircraft attack. It is close to .the coast on the east and south, which means that not only will warnings of impend ing attacks be very short, but also that the enemy will be able to take advantage of winds to reduce still further the period during which he is obliged to remain over British soil; the time available to the defending squadrons to get off, climb to the necessary height, find and stop the enemy will often be less than twenty minutes. Another added danger lies in attacks of aircraft on merchant shipping. If a map of ocean trade routes be opened and thereon is painted the area within range of foreign aircraft bases, this area will be found to cover most of our trade routes at one point or another. This is particularly impressive in the Mediterranean. So far the development of aircraft tends to add to the difficulty of imperial defence—but there is another side to the picture.
Aircraft forms a most effective means of defence against the possibility of overseas invasion. The invading force can be at tacked while still many miles out at sea and such attacks are likely to result in severe damage both to transport and to the moral of the troops they carry. Again, during the process of disembarka tion, ships at anchor and men in open boats, form easy targets to aircraft. In fact it is now generally admitted that landing on a hostile coast is impracticable unless air superiority has first been obtained. It would be difficult to do this unless a land base is first established within easy range of the defenders, since aircraft working from carriers are at a serious disadvantage when opposed to aircraft working from land. It would therefore appear that aircraft forms a most valuable means of coast defence for certain parts of the empire such as Australia. And there is a further point to remember. Guns mounted for coast defence are fixed and immobile. They represent a very large capital ex penditure which can be used for no other purpose and may never be required at all. Substitute aeroplanes for guns and we not only have the means of attacking the hypothetical invader at a vastly greater range, but we can use these aircraft for other pur poses. A squadron at, say, Singapore may be sent to prevent trouble on the north-west frontier of India and if the situation in the Far East became serious could be moved back to Singapore at short notice.
It would manifestly be expensive to keep enough aeroplane squadrons to meet all possible eventualities in any part of the world and there is no necessity to do so. Aircraft are very mobile aeroplanes have already flown to every part of the British empire in the eastern hemisphere and all that remains is to develop these imperial air routes that have already been blazed. Such an air route from Cairo, through Palestine and `Iraq to India, and on via Burma to Singapore and Australia, would give possibilities of the utmost value for rapid concentration at any threatened or troublesome spot and such power of concentration would have great deterrent effect against a potential enemy. With another route from Cairo to the Cape, with a branch to Nigeria, the problem of imperial defence and control assumes another aspect. These routes may be regarded as the modern counterparts of the roads which linked up the parts of the Roman empire. But to gain value from them we must never look upon aeroplane squad rons as fixed garrisons but as mobile units, located normally at some station but ready to move to any point.