Difficult as it is to arrive at exact statistics of commerce destruction in the old wars, one thing seems certain—that the bulk of captures, which were reckoned in hundreds and sometimes even in thousands, were due to the action of privateers. Further, it seems certain that, reckoning at least by numbers, the greater part of the damage was done by small privateers operating close to their bases, either home or colonial, against coastwise and local traffic. The complaints of merchants, so far as they are known, relate mainly to this kind of work in the West Indies and home waters, while accounts of serious captures by large privateers on the high seas are comparatively rare. The actual damage done by the swarm of small vessels may not have been great, but its moral effects were very serious. It was impossible for the strongest Governments to ignore them, and the consequence was a chronic disturbance of the larger strategical dispositions. While these dispositions were adequate to check the operations of large privateers acting in the same way as regular cruisers, the smaller ones found very free play amidst the ribwork of the protective system, and they could only be dealt with by filling up the spaces with a swarm of small cruisers to the serious detriment of the larger arrangements. Even so, the proximity of the enemy's ports made escape so easy, that the work of repression was very ineffective. The state of the case was indeed almost identical with a people's war. The ordinary devices of strategy failed to deal with it, as completely as Napoleon's broadly planned methods failed to deal with the guerilleros in Spain, or as our own failed for so long in South Africa.
By the abolition of privateering, then, it would seem that the most disturbing part of the problem has been eliminated. It is, of course, uncertain how far the Declaration of Paris will hold good in practice. It is still open even to the parties to it to evade its restrictions to a greater or less extent by taking up and commissioning merchantmen as regular ships of war. But it is unlikely that such methods will extend beyond the larger privately owned vessels. Any attempt to revive in this way the old picaresque methods could only amount to a virtual repudiation of statutory international law, which would bring its own retribution. Moreover, for home waters at least, the conditions which favoured this picaresque warfare no longer exist. In the old wars the bulk of our trade came into the Thames, and thence the greater part of it was distributed in small coasting vessels. It was against this coastwise traffic that the small, short-range privateers found their opportunity and their richest harvest. But, now that so many other great centres of distribution have established themselves, and that the bulk of the distribution is done by internal lines of communication, the Channel is no longer the sole artery, and the old troublesome disturbance can be avoided without a vital dislocation of our commercial system.
The probability, then, is that in the future the whole problem will be found to be simplified, and that the work of commerce protection will lie much more within the scope of large strategical treatment than it ever did before, with the result that the change should be found to tell substantially in favour of defence and against attack.
The reduction of range of action is scarcely less important. In the old days a cruising ship could be stored for six months, and so long as she could occasionally renew her fuel and water, she was free to range the sea outside the defended areas for the whole of the period with unimpaired vitality. For such pelagic operations her movement was practically unrestricted. She could run for two or three days from a superior enemy or chase for as long without loss of energy, and she could wait indefinitely at a likely spot, or change her ground, as danger or hope of plunder dictated. So long as she had men left to man her prizes, her power of mischief was almost unlimited. All this is now changed. The capacity of each cruise of a ship to-day is very small. She is confined to short dashes within a strategically defended area, or if she is bent on pelagic operations, is compelled to proceed so far to find undefended waters that her coal will scarcely permit of more than a few days' actual cruising. A couple of chases at high speed during that period may force her to return at once, subject only to the precarious possibility of renewing her coal from a prize. She has, further, to face the fact that manning prizes must necessarily reduce her capacity for speed, which depends so much on a fully manned engine-room. This will tend to jeopardise her chances of return through or near defended areas. The only escape from this difficulty is to sink the captured ship. But this course has objections scarcely less weighty than the other. No Power will incur the odium of sinking a prize with all hands, and their removal to the captor's ship takes time, especially in bad weather, and the presence of such prisoners in a cruiser in any number soon becomes a serious check on her fighting power. In the case of large ships, moreover, the work of destruction is no easy matter. In the most favourable circumstances it takes a considerable time, and thus not only eats into the cruiser's endurance, but decreases her chances of evasion.
From these and similar considerations it is obvious that the possibilities of operations on the great trade-routes are much less extensive than they were formerly, while to speak of cruisers "infesting" those routes is sheer hyperbole. Under modern conditions it is scarcely more feasible than it would be to keep up a permanent blockade of the British Islands. It would require a flow of ships in such numbers as no country but our own can contemplate possessing, and such as could not be maintained without having first secured a very decided preponderance at sea. The loss of radius of action therefore, though it does not increase the power of defence, sensibly lessens that of attack by pelagic operations.
For the great increase in the powers of defence we must turn to the extraordinary development in the means of distant communication. Under former conditions it was possible for a cruising ship to remain for days upon a fertile spot and make a number of captures before her presence was known. But since most large merchantmen have been fitted with wireless installations, she cannot now attack a single one of them without fear of calling down upon her an adversary. Moreover, when she is once located, every ship within wireless reach can be warned of her presence and avoid her. She must widely and constantly shift her position, thereby still further reducing her staying power. On the whole, then, it would appear that in so far as modern developments affect the problem, they certainly render pelagic operations far more difficult and uncertain than they used to be. Upon the great routes the power of attack has been reduced and the means of evasion has increased to such an extent as to demand entire reconsideration of the defence of trade between terminal areas. The whole basis of the old system would seem to be involved. That basis was the convoy system, and it now becomes doubtful whether the additional security which convoys afforded is sufficient to outweigh their economical drawbacks and their liability to cause strategical disturbance.
Over and above the considerations already noticed, there are three others, all of which favour the security of our trade by permitting a much more extended choice of route. The first is, that steam vessels are not forced by prevailing winds to keep to particular courses. The second is, that the improvements in the art of navigation no longer render it so necessary to make well-known landfalls during transit. The third is, that the multiplication of our great ports of distribution have divided the old main flow of trade to the Channel into a number of minor streams that cover a much wider area and demand a greater distribution of force for effective attack. It will be obvious that the combined effect of these considerations is to increase still further the chances of individual vessels evading the enemy's cruisers and to lessen the risk of dispensing with escort.
Nor are the new practical difficulties of sporadic operations on the great routes the only arguments that minimise the value of convoys. We have also to remember that while the number of vessels trading across the ocean has enormously increased since 1815, it is scarcely possible, even if the abolition of privateering prove abortive, that the number of cruisers available for pelagic attack could exceed, or even equal, the number employed in sailing days. This consideration, then, must also be thrown into the scale against convoys; for it is certain that the amount of serious operative damage which an enemy can do to our trade by pelagic operation is mainly determined by the ratio which his available cruiser strength bears to the volume of that trade. This aspect of the question is, however, part of a much wider one, which concerns the relation which the volume of our trade bears to the difficulty of its defence, and this must be considered later.
It remains, first, to deal with the final link in the old system of defence. The statement that the great routes were left undefended will seem to be in opposition to a prevailing impression derived from the fact that frigates are constantly mentioned as being "on a cruise." The assumption is that they in effect patrolled the great routes. But this was not so, nor did they rove the sea at will. They constituted a definite and necessary part of the system. Though that system was founded on a distinction between defended terminals and undefended routes, which was a real strategical distinction, it was impossible to draw an actual line where the one sphere began and the other ended. Outside the regularly defended areas lay a region which, as the routes began to converge, was comparatively fertile. In this region enemies' cruisers and their larger privateers found the mean between risk and profit. Here too convoys, as they entered the zone, were in their greatest danger for fear of their escorts being overpowered by raiding squadrons. Consequently it was the practice, when the approach of convoys was expected, to throw forward from the defended area groups of powerful cruisers, and even battleship divisions, to meet them and reinforce their escorts. Outward-bound convoys had their escorts similarly strengthened till they were clear of the danger zone. The system was in regular use both for home and colonial areas. In no sense did it constitute a patrol of the routes. It was in practice and conception a system of outposts, which at seasons of special risk amounted to an extension of the defended areas combining with a reinforcement of the convoy escorts. Focal points of lesser importance, such as Capes Finisterre and St. Vincent, were similarly held by one or two powerful cruisers, and if necessary by a squadron.
As has been already explained, owing to the peculiar conditions of the sea and the common nature of maritime communications, these dispositions were adopted as well for attack as defence, and the fertile areas, for the defence of which a frigate captain was sent "on a cruise," were always liable to bring him rich reward. His mission of defence carried with it the best opportunities for attack.
In the full development of the system patrol lines did exist, but not for the great routes. They were established to link up adjacent defended areas and as a more scientific organisation of the cruiser outposts. In 1805 the Gibraltar and the home areas were thus connected by a patrol line which stretched from Cape St. Vincent through the Finisterre focal area to Cape Clear, with a branch extending to the strategical centre off Ushant. The new system was introduced at a time when we had reason to expect that the French and Spanish fleets were to be devoted entirely to operations in small raiding squadrons against our trade and colonies. Special provision was therefore necessary to locate any such squadrons that might elude the regular blockades, and to ensure that they should be adequately pursued. The new lines were in fact intelligence patrols primarily, though they were also regarded as the only means of protecting efficiently the southern trade-route where it was flanked by French and Spanish ports.24
The whole system, it will be observed, though not conflicting with the main object of bringing the enemy's fleets to action, did entail an expenditure of force and deflecting preoccupations such as are unknown in land warfare. Large numbers of cruisers had to be employed otherwise than as the eyes of the battle-squadrons, while the coming and going of convoys produced periodical oscillations in the general distribution.
Embarrassing as was this commercial deflection in the old wars, an impression appears to prevail that in the future it must be much more serious. It is argued plausibly enough not only that our trade is far larger and richer than it was, but also that, owing to certain well-known economic changes, it is far more a matter of life and death to the nation than in the days when food and raw material did not constitute the bulk of our imports. In view of the new conditions it is held that we are more vulnerable through our trade now than formerly, and that, consequently, we must devote relatively more attention and force to its defence.
If this were true, it is obvious that war with a strong naval combination would present difficulties of the most formidable kind, greater indeed than we have ever experienced; for since with modern developments the demand for fleet cruisers is much greater than formerly, the power of devoting cruisers to trade defence is relatively much less.
It cannot be denied that at first sight the conclusion looks irreproachable. But on analysis it will be found to involve two assumptions, both of which are highly questionable. The first is, that the vulnerability of a sea Power through its maritime trade is as the volume of that trade. The second is, that the difficulty of defending sea-borne trade is also as its volume—that is to say, the larger the amount of the trade, the larger must be the force devoted to its protection. This idea indeed is carried so far, that we are frequently invited to fix the standard of our naval strength by comparing it with the proportion which the naval strength of other Powers bears to their sea-borne trade.
It is hoped that the foregoing sketch of our traditional system of trade defence will avail to raise a doubt whether either assumption can be accepted without very careful consideration. In the history of that system there is no indication that it was affected by the volume of the trade it was designed to protect. Nor has any one succeeded in showing that the pressure which an enemy could exert upon us through our commerce increased in effect with the volume of our seaborne trade. The broad indications indeed are the other way—that the greater the volume of our trade, the less was the effective impression which an enemy could make upon it, even when he devoted his whole naval energies to that end. It is not too much to say that in every case where he took this course his own trade dwindled to nothing, while ours continually increased.
It may be objected that this was because the only periods in which he devoted his main efforts to trade destruction were when we had dominated his navy, and being no longer able to dispute the command, he could do no more than interfere with its exercise. But this must always be so whether we have positively dominated his navy or not. If he tries to ignore our battle-fleets, and devotes himself to operations against trade, he cannot dispute the command. Whatever his strength, he must leave the command to us. He cannot do both systematically, and unless he attacks our trade systematically by sustained strategical operation, he cannot hope to make any real impression.
If, now, we take the two assumptions and test them by the application of elementary principles, both will appear theoretically unsound. Let us take first the relation of vulnerability to volume. Since the object of war is to force our will upon the enemy, the only way in which we can expect war on commerce to serve our end is to inflict so much damage upon it as will cause our enemy to prefer peace on our terms to a continuation of the struggle. The pressure on his trade must be insupportable, not merely annoying. It must seriously cripple his finance or seriously threaten to strangle his national life and activities. If his total trade be a hundred millions, and we succeed in destroying five, he will feel it no more than he does the ordinary fluctuations to which he is accustomed in time of peace. If, however, we can destroy fifty millions, his trade equilibrium will be overthrown, and the issue of the war will be powerfully affected. In other words, to affect the issue the impression made on trade must be a percentage or relative impression. The measure of a nation's vulnerability through its trade is the percentage of destruction that an enemy can effect.
Now, it is true that the amount of damage which a belligerent can inflict with a given force on an enemy's commerce will vary to some extent with its volume; for the greater the volume of commerce, the more fertile will be the undefended cruising grounds. But no matter how fertile such areas might be, the destructive power of a cruiser was always limited, and it must be still more limited in the future. It was limited by the fact that it was physically impossible to deal with more than a certain number of prizes in a certain time, and, for the reasons already indicated, this limit has suffered a very marked restriction. When this limit of capacity in a given force is passed, the volume of commerce will not affect the issue; and seeing how low that capacity must be in the future and how enormous is the volume of our trade, the limit of destructive power, at least as against ourselves, provided we have a reasonably well-organised system of defence, must be relatively low. It must, in fact, be passed at a percentage figure well within what we have easily supported in the past. There is reason, therefore, to believe that so far from the assumption in question being true, the effective vulnerability of sea-borne trade is not in direct but in inverse proportion to its volume. In other words, the greater the volume, the more difficult it is to make an effective percentage impression.
Similarly, it will be observed that the strain of trade defence was proportioned not to the volume of that trade, but to the number and exposure of its terminals and focal points. Whatever the volume of the trade these remained the same in number, and the amount of force required for their defence varied only with the strength that could readily be brought to bear against them. It varied, that is, with the distribution of the enemy's bases and the amount of his naval force. Thus in the war of 1812 with the United States, the West Indian and North American areas were much more exposed than they had been when we were at war with France alone and when American ports were not open to her as bases. They became vulnerable not only to the United States fleet, but also in a much higher degree to that of France, and consequently the force we found necessary to devote to trade defence in the North Atlantic was out of all proportion to the naval strength of the new belligerent. Our protective force had to be increased enormously, while the volume of our trade remained precisely the same.
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.