Some Principles of Maritime Strategy
This relation of trade defence to terminal and focal areas is of great importance, for it is in the increase of such areas in the Far East that lies the only radical change in the problem. The East Indian seas were always of course to some extent treated as a defended area, but the problem was simplified by the partial survival in those regions of the old method of defence. Till about the end of the seventeenth century long-range trade was expected to defend itself, at least outside the home area, and the retention of their armament by East Indiamen was the last survival of the practice. Beyond the important focal area of St. Helena they relied mainly on their own power of resistance or to such escort as could be provided by the relief ships of the East Indian station. As a rule, their escort proper went no farther outward-bound than St. Helena, whence it returned with the homeward-bound vessels that gathered there from India, China, and the South Sea whaling grounds. The idea of the system was to provide escort for that part of the great route which was exposed to attack from French or Spanish colonial bases on the African coasts and in the adjacent islands.
For obvious reasons this system would have to be reconsidered in the future. The expansion of the great European Powers have changed the conditions for which it sufficed, and in a war with any one of them the system of defended terminal and focal areas would require a great extension eastward, absorbing an appreciable section of our force, and entailing a comparatively weak prolongation of our chain of concentrations. Here, then, we must mark a point where trade defence has increased in difficulty, and there is one other.
Although minor hostile bases within a defended area have lost most of their menace to trade, they have acquired as torpedo bases a power of disturbing the defence itself. So long as such bases exist with a potent flotilla within them, it is obvious that the actual provision for defence cannot be so simple a matter as it was formerly. Other and more complex arrangements may have to be made. Still, the principle of defended areas seems to remain unshaken, and if it is to work with its old effectiveness, the means and the disposition for securing those areas will have to be adapted to the new tactical possibilities. The old strategical conditions, so far as can be seen, are unaltered except in so far as the reactions of modern material make them tell in favour of defence rather than of attack.
If we desire to formulate the principles on which this conclusion rests we shall find them in the two broad rules, firstly, that the vulnerability of trade is in inverse ratio to its volume, and secondly, that facility of attack means facility of defence. The latter, which was always true, receives special emphasis from modern developments. Facility of attack means the power of exercising control. For exercise of control we require not only numbers, but also speed and endurance, qualities which can only be obtained in two ways: it must be at the cost of armour and armament, or at the cost of increased size. By increasing size we at once lose numbers. If by sacrificing armament and armour we seek to maintain numbers and so facilitate attack, we at the same time facilitate defence. Vessels of low fighting power indeed cannot hope to operate in fertile areas without support to overpower the defence. Every powerful unit detached for such support sets free a unit on the other side, and when this process is once begun, there is no halting-place. Supporting units to be effective must multiply into squadrons, and sooner or later the inferior Power seeking to substitute commerce destruction for the clash of squadrons will have squadronal warfare thrust upon him, provided again the superior Power adopts a reasonably sound system of defence. It was always so, and, so far as it is possible to penetrate the mists which veil the future, it would seem that with higher mobility and better means of communication the squadronal stage must be reached long before any adequate percentage impression can have been made by the sporadic action of commerce destroyers. Ineffectual as such warfare has always been in the past, until a general command has been established, its prospects in the future, judged by the old established principles, are less promising than ever.
Finally, in approaching the problem of trade protection, and especially for the actual determination of the force and distribution it requires, there is a dominant limitation to be kept in mind. By no conceivable means is it possible to give trade absolute protection. We cannot make an omelette without breaking eggs. We cannot make war without losing ships. To aim at a standard of naval strength or a strategical distribution which would make our trade absolutely invulnerable is to march to economic ruin. It is to cripple our power of sustaining war to a successful issue, and to seek a position of maritime despotism which, even if it were attainable, would set every man's hand against us. All these evils would be upon us, and our goal would still be in the far distance. In 1870 the second naval Power in the world was at war with an enemy that could not be considered a naval Power at all, and yet she lost ships by capture. Never in the days of our most complete domination upon the seas was our trade invulnerable, and it never can be. To seek invulnerability is to fall into the strategical vice of trying to be superior everywhere, to forfeit the attainment of the essential for fear of risking the unessential, to base our plans on an assumption that war may be waged without loss, that it is, in short, something that it never has been and never can be. Such peace-bred dreams must be rigorously abjured. Our standard must be the mean of economic strength—the line which on the one hand will permit us to nourish our financial resources for the evil day, and on the other, when that day comes, will deny to the enemy the possibility of choking our financial vigour by sufficiently checking the flow of our trade.
III. ATTACK, DEFENCE, AND SUPPORT OF MILITARY EXPEDITIONS
The attack and defence of oversea expeditions are governed in a large measure by the principles of attack and defence of trade. In both cases it is a question of control of communications, and in a general way it may be said, if we control them for the one purpose, we control them for the other. But with combined expeditions freedom of passage is not the only consideration. The duties of the fleet do not end with the protection of the troops during transit, as in the case of convoys, unless indeed, as with convoys, the destination is a friendly country. In the normal case of a hostile destination, where resistance is to be expected from the commencement of the operations, the fleet is charged with further duties of a most exacting kind. They may be described generally as duties of support, and it is the intrusion of these duties which distinguish the naval arrangements for combined operations most sharply from those for the protection of trade. Except for this consideration there need be no difference in the method of defence. In each case the strength required would be measured by the dangers of interference in transit. But as it is, that standard will not serve for combined expeditions; for however small those risks, the protective arrangements must be sufficiently extensive to include arrangements for support.
Before dealing with this, the most complex aspect of the question, it will be well to dismiss attack. From the strategical point of view its principles differ not at all from those already laid down for active resistance of invasion. Whether the expedition that threatens us be small or of invasion strength, the cardinal rule has always been that the transports and not the escort must be the primary objective of the fleet. The escort, according to the old practice, must be turned or contained, but never treated as a primary objective unless both turning and containing prove to be impracticable. It is needless to repeat the words of the old masters in which this principle lies embalmed. It is seldom that we find a rule of naval strategy laid down in precise technical terms, but this one is an exception. In the old squadronal instructions, "The transports of the enemy are to be your principal object," became something like a common form.
Nor did this rule apply only to cases where the transports were protected by a mere escort. It held good even in the exceptional cases where the military force was accompanied or guarded by the whole available battle strength of the enemy. We have seen how in 1744 Norris was prepared to follow the French transports if necessary with his whole force, and how in 1798 Nelson organised his fleet in such a way as to contain rather than destroy the enemy's battle-squadron, so that he might provide for an overwhelming attack upon the transports.
Exceptions to this as to all strategical rules may be conceived. Conditions might exist in which, if the enemy's battle-fleet accompanied his transports, it would be worth our while, for ulterior objects of our own, to risk the escape of the transports in order to seize the opportunity of destroying the fleet. But even in such a case the distinction would be little more than academical; for our best chance of securing a decisive tactical advantage against the enemy's fleet would usually be to compel it to conform to our movements by threatening an attack on the transports. It is well known that it is in the embarrassment arising from the presence of transports that lies the special weakness of a fleet in charge of them.
There is, however, one condition which radically differentiates comparatively small expeditions from great invasions and that is the power of evasion. Our experience has proved beyond dispute that the navy alone cannot guarantee defence against such expeditions. It cannot be sure of preventing their sailing or of attacking them in transit, and this is especially the case where an open sea gives them a free choice of route, as in the case of the French expeditions against Ireland. It is for this reason that, although an adequate navy has always proved sufficient to prevent an invasion, for defence against expeditions it must be supplemented by a home army. To perfect our defence, or, in other words, our power of attack, such an army must be adequate to ensure that all expeditions small enough to evade the fleet shall do no effective harm when they land. If in numbers, training, organisation, and distribution it is adequate for this purpose, an enemy cannot hope to affect the issue of the war except by raising his expeditions to invasion strength, and so finding himself involved in a problem that no one has ever yet solved for an uncommanded sea.
Still, even for expeditions below invasion strength the navy will only regard the army as a second line, and its strategy must provide in the event of evasion for co-operation with that line. By means of a just distribution of its coastal flotilla it will provide for getting contact with the expedition at the earliest moment after its destination is declared. It will press the principle of making the army its objective to the utmost limit by the most powerful and energetic cruiser pursuit, and with wireless and the increased ratio of cruiser speed, such pursuit is far more formidable than it ever was. No expedition nowadays, however successful its evasion, can be guaranteed against naval interruption in the process of landing. Still less can it be guaranteed against naval interference in its rear or flanks while it is securing its front against the home army. It may seek by using large transports to reduce their number and secure higher speed, but while that will raise its chance of evasion, it will prolong the critical period of landing. If it seek by using smaller transports to quicken disembarkation, that will decrease its chances of evasion by lowering its speed and widening the sea area it will occupy in transit. All the modern developments in fact which make for defence in case of invasion over an uncommanded sea also go to facilitate timely contact with an expedition seeking to operate by evasion. Nor must it be forgotten, since the problem is a combined one, that the corresponding developments ashore tell with little less force in favour of the defending army. Such appear to be the broad principles which govern an enemy's attempts to act with combined expeditions in our own waters, where by hypothesis we are in sufficient naval strength to deny him permanent local command. We may now turn to the larger and more complex question of the conduct of such expeditions where the naval conditions are reversed.
By the conduct, be it remembered, we mean not only their defence but also their support, and for this reason the starting-point of our inquiry is to be found, as above indicated, in the contrast of combined expeditions with convoys. A convoy consists of two elements—a fleet of merchantmen and an escort. But a combined expedition does not consist simply of an army and a squadron. It is an organism at once more complex and more homogeneous. Its constitution is fourfold. There is, firstly, the army; secondly, the transports and landing flotilla—that is, the flotilla of flat-boats and steamboats for towing them, all of which may be carried in the transports or accompany them; thirdly, the "Squadron in charge of transports," as it came to be called, which includes the escort proper and the supporting flotilla of lighter craft for inshore work; and lastly, the "Covering squadron."
Such at least is a combined expedition in logical analysis. But so essentially is it a single organism, that in practice these various elements can seldom be kept sharply distinct. They may be interwoven in the most intricate manner. Indeed to a greater or less extent each will always have to discharge some of the functions of the others. Thus the covering squadron may not only be indistinguishable from the escort and support, but it will often provide the greater part of the landing flotilla and even a portion of the landing force. Similarly, the escort may also serve as transport, and provide in part not only the supporting force, but also the landing flotilla. The fourfold constitution is therefore in a great measure theoretical. Still its use is not merely that it serves to define the varied functions which the fleet will have to discharge. As we proceed it will be seen to have a practical strategical value.
From a naval point of view it is the covering squadron which calls first for consideration, because of the emphasis with which its necessity marks not only the distinction between the conduct of combined expeditions and the conduct of commercial convoys, but also the fact that such expeditions are actually a combined force, and not merely an army escorted by a fleet.
In our system of commerce protection the covering squadron had no place. The battle-fleet, as we have seen, was employed in holding definite terminal areas, and had no organic connection with the convoys. The convoys had no further protection than their own escort and the reinforcements that met them as they approached the terminal areas. But where a convoy of transports forming part of a combined expedition was destined for an enemy's country and would have to overcome resistance by true combined operations, a covering battle-squadron was always provided. In the case of distant objectives it might be that the covering squadron was not attached till the whole expedition assembled in the theatre of operations; during transit to that theatre the transports might have commerce protection escort only. But once the operations began from the point of concentration, a covering squadron was always in touch.
It was only where the destination of the troops was a friendly country, and the line of passage was well protected by our permanent blockades, that a covering squadron could be dispensed with altogether. Thus our various expeditions for the assistance of Portugal were treated exactly like commercial convoys, but in such cases as Wolfe's expedition to Quebec or Amherst's to Louisburg, or indeed any of those which were continually launched against the West Indies, a battle-squadron was always provided as an integral part in the theatre of operations. Our arrangements in the Crimean War illustrate the point exactly. Our troops were sent out at first to land at Gallipoli in a friendly territory, and to act within that territory as an army of observation. It was not a true combined expedition, and the transports were given no covering squadron. Their passage was sufficiently covered by our Channel and Mediterranean fleets occupying the exits of the Baltic and the Black Sea. But so soon as the original war plan proved ineffective and combined offensive operations against Sebastopol were decided on, the Mediterranean fleet lost its independent character, and thenceforth its paramount function was to furnish a covering squadron in touch with the troops.
Seeing how important are the support duties of such a force, the term "Covering squadron" may seem ill-chosen to describe it. But it is adopted for two reasons. In the first place, it was the one employed officially in our service on the last mentioned occasion which was our last great combined expedition. In preparing the descent on the Crimea, Sir Edmund Lyons, who was acting as Chief of the Staff to Sir James Dundas, and had charge of the combined operations, organised the fleet into a "Covering squadron" and a "Squadron in charge of transports." In the second place, the designation serves to emphasise what is its main and primary function. For important as it is to keep in mind its support duties, they must not be permitted to overshadow the fact that its paramount function is to prevent interference with the actual combined operations—that is, the landing, support, and supply of the army. Thus in 1705, when Shovel and Peterborough were operating against Barcelona, Shovel was covering the amphibious siege from the French squadron in Toulon. Peterborough required the assistance of the marines ashore to execute a coup de main, and Shovel only consented to land them on the express understanding that the moment his cruisers passed the signal that the Toulon squadron was putting to sea, they would have to be recalled to the fleet no matter what the state of the land operations. And to this Peterborough agreed. The principle involved, it will be seen, is precisely that which Lyons's term "Covering squadron" embodies.
To quote anything that happened in the Crimean War as a precedent without such traditional support will scarcely appear convincing. In our British way we have fostered a legend that so far as organisation and staff work were concerned that war was nothing but a collection of deterrent examples. But in truth as a combined operation its opening movement both in conception and organisation was perhaps the most daring, brilliant, and successful thing of the kind we ever did. Designed as the expedition was to assist an ally in his own country, it was suddenly called upon without any previous preparation to undertake a combined operation of the most difficult kind against the territory of a well-warned enemy. It involved a landing late in the year on an open and stormy coast within striking distance of a naval fortress which contained an army of unknown strength, and a fleet not much inferior in battle power and undefeated. It was an operation comparable to the capture of Louisburg and the landing of the Japanese in the Liaotung Peninsula, but the conditions were far more difficult. Both those operations had been rehearsed a few years previously, and they had been long prepared on the fullest knowledge. In the Crimea everything was in the dark; even steam was an unproved element, and everything had to be improvised. The French had practically to demobilise their fleet to supply transport, and so hazardous did the enterprise appear, that they resisted its being undertaken with every military argument. We had in fact, besides all the other difficulties, to carry an unwilling ally upon our backs. Yet it was accomplished, and so far at least as the naval part was concerned, the methods which achieved success mark the culmination of all we had learnt in three centuries of rich experience.
The first of the lessons was that for operations in uncommanded or imperfectly commanded seas there was need of a covering squadron differentiated from the squadron in charge of transports. Its main function was to secure the necessary local command, whether for transit or for the actual operations. But as a rule transit was secured by our regular blockading squadrons, and generally the covering squadron only assembled in the theatre of operations. When therefore the theatre was within a defended terminal area, as in our descents upon the northern and Atlantic coasts of France, then the terminal defence squadron was usually also sufficient to protect the actual operations. It thus formed automatically the covering squadron, and either continued its blockade, or, as in the case of our attack on St. Malo in 1758, took up a position between the enemy's squadron and the expedition's line of operation. If, however, the theatre of operation was not within a terminal area, or lay within a distant one that was weakly held, the expedition was given its own covering squadron, in which the local squadron was more or less completely merged. Whatever, in fact, was necessary to secure the local control was done, though, as we have seen, and must presently consider more fully, this necessity was not always the standard by which the strength of the covering squadron was measured.
The strength of the covering squadron being determined, the next question is the position or "tract" which it should occupy. Like most other strategical problems, it is "an option of difficulties." In so far as the squadron is designed for support—that is, support from its men, boats, and guns—it will be desirable to station it as near as possible to the objective; but as a covering squadron, with the duty of preventing the intrusion of an enemy's force, it should be as far away as possible, so as to engage such a force at the earliest possible moment of its attempt to interfere. There is also the paramount necessity that its position must be such that favourable contact with the enemy is certain if he tries to interrupt. Usually such certainty is only to be found either in touch with the enemy's naval base or in touch with your own landing force. Where the objective is the local naval base of the enemy these two points, of course, tend to be identical strategically, and the position of the covering squadron becomes a tactical rather than a strategical question. But the vital principle of an independent existence holds good, and no matter how great the necessity of support, the covering squadron should never be so deeply engaged with the landing force as to be unable to disentangle itself for action as a purely naval unit in time to discharge its naval function. In other words, it must always be able to act in the same way as a free field army covering a siege.
Where the objective of the expedition is not the local naval base, the choice of a position for the covering squadron will turn mainly on the amount of support which the army is likely to require. If it cannot act by surprise, and serious military resistance is consequently to be expected, or where the coast defences are too strong for the transport squadron to overpower, then the scale will incline to a position close to the army, though the extent to which, under modern conditions, ships at sea can usefully perform the delicate operation of supporting an infantry attack with gun fire, except by enfilading the enemy's position, remains to be proved. A similar choice will be indicated where strong support of men and boats is required, as when a sufficiency of flat-boats and steam towage cannot be provided by the transports and their attendant squadron; or again where the locality is such that amphibious operations beyond the actual landing are likely to be called for, and the assistance of a large number of boats and seamen acting with the army is necessary to give it the amphibious tactical mobility which it would otherwise lack. Such cases occurred at Quebec in 1759, where Saunders took his covering battle-squadron right up the St. Lawrence, although its covering functions could have been discharged even better by a position several hundreds of miles away from the objective; and again in 1800 at Alexandria, where Lord Keith ran the extremest hazard to his covering functions in order to undertake the supply of General Abercromby's army by inland waters and give him the mobility he required.