Sea-power had in past wars proved the decisive factor. Napoleon was defeated by the British navy; sea-power decided the American Civil War; and it was clear that the influence of sea-power in this war might also be decisive. As a matter of fact, it was. The British navy silently, quickly, without fighting a major battle, in a sense won the war.

The war was really won by a good many factors, not one of which could have been omitted. Thus, the Belgians in their first resistance saved France and therefore won the war; the French in the battle of the Marne threw back the Germans and decided the issue of the war; at the same time the Russians, by sacrificing their army in Poland, compelled the Germans to send troops east, and this allowed the French to win the battle of the Marne. The coming of the British army and of the American army were both events without which the war could not have been won; but, in a real sense, all of these must have failed but for the blockade established by the British fleet.

The great weakness in the German position, the very thing the Germans were fighting the war to correct, was their lack of raw materials necessary for German industry in peace or war. Nor could they collect in time of peace a sufficient store of cotton, wool, rubber, and copper without advertising their intention to fight a war. Some months' supply they might have on hand when the war broke out, but not more. A time would come, therefore, when it would be extremely difficult for them to get along without new supplies or without changing entirely their whole basis of living. They knew that if the British joined the war they would at once blockade Germany and stop the stream of supplies from outside.

It meant a complete transformation of German industry. Everything in Germany would have to support the war, because Germany would have to make everything she needed. Nothing should be made that the Germans could not themselves use, for otherwise it could not be sold and would therefore become waste. Substitutes they thought they could find for some things; enough supplies of others they thought they could smuggle through the British blockade with the help of the Dutch, the Danes, and the Swedes, who could claim rights, as neutral countries, to import such things for their own use, and who would then of course ship them to Germany. At any rate, the Germans thought their army would win the war before this economic pressure created by the sea-power could cripple them enough to bring the war to an end, They might have to get along without some things, eat food they did not particularly like, but there would be enough to eat and to wear and to fight with, and the end would be glorious. The British should be made to pay when the war was over.

The Germans thought it possible, however, that they might forestall the blockade. Their own fleet should slip out before the British fleet sailed, and once on the open ocean it could give the British a chase—perhaps meet and defeat them. It would get its food and coal from the United States and other neutral countries; and by dividing the British fleet prevent the blockade of Germany. Fast German ships should be also equipped to capture British merchant vessels, and they would thus reduce the stream of supplies going to England, which was no less dependent than Germany upon raw material from outside if she was to continue the war. It might be that they could in this way, by these commerce raiders, sink enough ships to make a difference.

Then there were the submarines. They should attempt to sink battleships and thus break the blockade; sink transports carrying troops across to France, steal into British harbors and sink the ships at anchor. If German ships could not sail the seas, it would then become a simple thing to loose thousands of floating mines. They would float along below the surface and, if a ship should touch one of them, it would explode and sink her. They would be carried by the tides and currents down upon the British fleet and sink it.

Everything depended for the British upon the successful work of the fleet. It must keep open the ocean so that the supplies could reach England on which the continuation of the war depended. The food of the British people, clothes for the soldiers, everything necessary for the war, depended upon the British merchant marine and the ability of the fleet to protect it against German cruisers, submarines, and mines. The whole issue of victory depended upon the adequacy of the work of the fleet.

At the outset the British were too quick for the Germans. The famous order described at the beginning of this chapter sent the British into action just in time to prevent the German escape. The German fleet was bottled up in its own ports before the war really began. There were a few German warships in Pacific and South American waters. Several German merchant ships were transformed into commerce raiders and for some months these were able to elude the vigilance of British and Japanese ships sent in pursuit. The Emden had a particularly thrilling and adventurous career.

But by Christmas of 1914 the German warships had been captured and sunk, and all commerce raiders had been rounded up. Meanwhile, the great harbors had been protected and a steel net had been erected across the mouth of the Thames River strong enough to resist submarines. This was a great engineering undertaking and its success meant much. Similar nets were created at once for the other British harbors, and one was even built practically across the Channel so as to stop mines floating down into the passage between England and France. These nets were composed of movable sections which could be opened at will. It became necessary—such was the cleverness of the Germans—to change the passage through the nets very often, because submarines would be waiting to sneak through the moment the net was opened at the former spot.

Thousands of British ships were transformed into mine-sweepers to clear the sea around the British Islands, a very dangerous and difficult work. Patrol boats to watch for submarines were sent out by dozens and then by hundreds. A screen of destroyers steamed up and down in front of the Grand Fleet practically throughout the duration of the war to ward off submarines and raiders. Week after week, month after month, the steady patrolling went on. The work of the submarine in sinking ships on the open ocean we shall have to tell about as the story goes on, but the success of the British fleet was complete. The entire British army, millions of men, was transported back and forth to France, practically without the loss of a man. Never for a moment was the army in France, or the French army (also dependent upon the British navy), without food, clothes, or ammunition, because of lack of transport. Despite the enormous number of ships sunk during the course of the war by the submarines, the British factories never stopped work, night or day, because of a failure of raw materials with which to continue.

In Germany, on the other hand, the blockade was so successful that things went from bad to worse. As the war grew longer, the measures which the Germans had originally invented to create substitutes or to reorganize industries became less and less adequate. While probably few actually died of starvation, civilians, and even soldiers, were wearing clothes and shoes made of paper, and were not getting enough fats and sweets to keep up health. The war came to an end with the German army beaten and practically in flight. It could hardly have been brought to that situation without the pressure of the blockade. The work of the British fleet was one of the most important single factors in winning the war.