II
Admiral Sir Cyprian Bridge regards the functions of defense by a navy as divisible into three main classifications. He says, "The above-mentioned three divisions are called in common speech, coast defense, colonial defense, and defense of commerce." From this classification we are given a hint as to what a sailor means by "naval supremacy," "freedom of the seas," and other terms so misused that to-day they mean nothing. "Coast defense" means defense against invasion; "colonial defense" means the safeguarding of distant possessions against enemy forces; the "defense of commerce" means such supremacy on the seas as will insure absolute safety of the mercantile marine from enemy commerce-destroyers.
To-day every great nation is waging a trade war. The industrial competition of peace is as keen as the competition of war. All the great Powers realized years ago that, to gain and keep their "place in the sun," it was necessary for them to construct navies that would insure to them a certain control of the seas for the protection of their commerce. In this way began the abnormal naval construction in which the Powers have vied with one another for supremacy.
A simple way of looking at the question, what constitutes the power of a fleet, is to consider the warship as merely a floating gun-platform. Even though this floating platform is the most complex piece of mechanism that was ever contrived by man, nevertheless its general function is simple. The war has given us enough experience to convince us that the backbone of a navy is, after all, the heavily armored ship of moderately high speed, carrying a very heavy armament. This floating gun-platform is the structure best fitted to carry large guns into battle, and to withstand the terrific punishment of the enemy's fire.
The battleship is to-day, notwithstanding the development of other types, queen of the seas. It is therefore not difficult to estimate the relative power of the fleets of different nations. In fact, a purely engineering estimate of this kind can be made, and the respective ranks of the world's naval powers ascertained. Germany has shown all through the war that she thoroughly appreciated the British naval supremacy. Her fleet has ventured little more than sporadic operations from the well-fortified bases behind Heligoland. It was probably the pressure of public opinion, and not the expectation that she would achieve anything of military advantage, that forced her to send her high-sea fleet into conflict with the British squadrons off Jutland.
If one should examine the course of this battle, which has been represented by lines graphically showing the paths of the British and German fleets, one could easily see how the British imposed their will upon the Germans in every turn that these lines make. It reminds one very much of the herding of sheep, for the German fleet was literally herded on May 31, 1916, from 5:36 in the afternoon until 9 o'clock that night. Admiral von Scheer, however, fought the only action which it was possible for him to fight. It was a losing action, and one which he knew, from a purely mathematical consideration, could not be successful.
Through the very definiteness of this understanding of what constitutes naval strength, Great Britain's navy until recently has remained a great potential force, becoming dynamic for only a few hours at Jutland, after which it returned to that mysterious northern base whence it seems to dominate the seas. Because of the potentiality of these hidden warships, thousands of vessels have traversed the ocean, freighted with countless tons of cargoes and millions of men for the Allies. Even at that psychological moment when the first hundred thousand were being transported to France, Germany refrained from a naval attack which might have turned the whole land campaign in her favor.
To-day, however, the world is awakening to a new idea of sea-power, to a new conception that will have a far-reaching influence on the future development of naval machinery.
Sir Cyprian Bridge has stated that one of the functions of a fleet is the defense of commerce. There is no more important function for a fleet than this. A nation may be subjugated by direct invasion, or it may be isolated from the world by blockade. If the blockade be sufficiently long, and effectively maintained, it will ruin the nation as effectually as direct invasion.
Thus, in the maintenance of a nation's merchant marine on the high seas, its navy exercises one of its most vital functions. There can, therefore, be no naval supremacy for a nation unless its commerce is assured of immunity from considerable losses through the attack of its enemy. It is idle for us to speak of our naval supremacy over Germany, when our navies are failing in one of their most important functions, and when our commerce is suffering such serious losses. The persons best qualified to judge are those who are most anxious regarding the present losses in mercantile tonnage.
While it has been shown that the submersible of to-day, as a fighting machine, is considerably limited, and in no sense endangers the existence of the capital ship, nevertheless in the new huge submersible it seems that the ideal commerce-destroyer has been found. This vessel possesses the necessary cruising radius to operate over sufficient distances to control important routes; it makes a surface speed great enough to run down cargo steamers, and has a superstructure to mount guns of considerable power (up to six-inch). It embodies almost all the qualifications of the light surface cruiser, with the additional tremendous advantage of being able to hide by submergence. To be completely successful, it must operate in flotillas of hundreds in waters that are opaque to aërial observation. Germany has but a limited number of these submersibles, otherwise she would be able to crush the Allied commerce.
The ideal submersible commerce-raider should be a vessel of such displacement that she could carry a sufficient number of large guns in her superstructure to enable her to fight off the attack of surface destroyers and the smaller patrol craft.[2] She should be capable of cruising over a large radius at high speed, both on the surface and submerged. The supersubmersible flotillas should comprise fifty or sixty of these units. The attack on the trade routes should be made by a number of flotillas operating at different points at unexpected times. To-day Germany has concentrated her submarine war particularly in the constricted waters about England. It is here that the shipping is most congested, and therefore the harvest is richest, but it is also easier to protect the trade routes over these limited areas of water by patrols, nets, etc., than it would be to protect the entire trans-oceanic length of the steamship lanes. If the submersible were capable of dealing directly with the destroyer in gun-fighting, a tremendous revolution would take place in the tactics of "submarine swatting." Then it would be difficult to see how the submersible could be dealt with.
Improvement in motive machinery is the vital necessity in the development of the submersible. The next few years may see unexpected strides taken in this direction. A great deal will also be accomplished in perfecting methods of receiving sounds under water, particularly in relation to ascertaining the direction of these sounds. When this is done, it will be possible for the submersible commander to tell a great deal about the positions of the vessels above him, and thus his artificial ears will compensate to a great extent for his blindness. By the addition of a greater number of torpedo-tubes, and the improvement of their centralized control in the hand of the commander at the periscope, along lines which we are now developing, it will be possible for the submersible to achieve a greater effectiveness in its torpedo fire. Probably torpedoes will then be used only against the more important enemy units, such as battleships, cruisers, and the like. To be certain of striking these valuable targets would be worth expending a number of torpedoes in salvo fire.
Whether the German U-boat campaign succeeds or not will be largely a question of the number of submersibles that the Central Powers can put into service, and to what extent the submersible will be developed during the present war.