German naval policy, no less wise for its own ends than for the British, has depended upon the submarine, whose importance may be easily exaggerated and easily underestimated. No submarine can approach the major fighting ships of a great fleet when that fleet is properly protected by torpedo-defense guns and fast destroyers and light cruisers. The deciding test of a submarine's power in this respect was the fruitless attempts of the best German submarines to reach the _Lion_ with a deathblow, when crippled, after the battle off Dogger Bank, she was being towed home at 5 knots an hour, under the protection of the destroyers. However, any isolated vessel, whether a merchantman or a man-of-war, is at the mercy of a submarine, which hunts the seas for this kind of target. It has only to lie in wait on the trade routes until its prey appears, submerging in case of danger. Then a torpedo sent home and a valuable piece of property goes to the bottom of the sea. What resourceful brigandage is to traffic on the highways, the German submarine became to British traffic on the seas. It is the sniper of naval warfare, but cannot give battle. It must find its protection under the sea, while all freight and all passengers, all the world's business is done on the surface of the sea; and the great guns of the dreadnoughts command the surface. [Illustration: George V, King of Great Britain and Emperor of India.] When brigandage becomes highly organized, it means enormous expense in increased police work, particularly if you cannot trail the brigands to their hiding places and force them to capitulate. In this case the brigands' hiding places are under the protection of powerful fortress guns and mine fields in secure harbors. The British navy, with over three thousand ships, including mine sweepers and auxiliaries of all sorts under Sir John Jellicoe's command, was forced to go to immense expense and pains in combating the submarine campaign. Many submarines were taken; but the Germans kept on building them. It was a war against an unseen and cunning foe, which required ceaseless vigilance and painstaking effort. The amount of material, as well as the amount of ships required in order to combat the submarines and also to keep the patrol intact from the British channel to Iceland, could it be enumerated, would stagger the imagination. Meanwhile, England had to go on building new dreadnoughts and cruisers and destroyers at top speed, with a view to increasing her rate of naval superiority over the Germans. Once the German fleet had come out and been beaten, then the British would be secure in victory, and they could spare many guns for the army and devote all their energy to the land campaign.