It is said that a single voyage in a German submarine is enough so seriously to try the nerves of officers and men that they need a prolonged rest before they are ready to resume their duties. Imagine the conditions under which they live! Hunted day and night by the relentless British destroyers, faced ever by strange and unfamiliar perils and by traps of which they know nothing, it is hardly a matter of surprise if their nerves give way.

The War has given us the most wonderful example the world has ever seen of what sea power means. Thanks to their undisputed command of the ocean, the Allies have been able to carry on operations in widely separated theatres practically free from any of the difficulties which would certainly have proved insurmountable in the presence of strong hostile forces afloat. We and our Allies have been able to transport men and munitions wherever we wished without serious hindrance, and even in the presence of hostile submarines we have only lost two or three transports in eighteen months of war. That, it must be admitted, is a very wonderful record.

Even the tragic blunder of the Dardanelles gave us a striking instance of what sea power can effect. We were able, thanks to the Navy, not merely to land huge forces in the face of the enemy, but we were able also to re-embark them without loss under circumstances which, by all the laws of war, should have meant an appalling list of casualties. There can be no doubt whatever that had the re-embarking troops on the Gallipoli Pensinsula tried to reach their ships without having firm command of the sea, not more than a very small percentage of them would have survived.

In considering the bearings of naval power to the great struggle as a whole, we must always keep in mind what the Germans expected and hoped when they declared war. We know, of course, that they did not expect Britain to enter the War. But at the same time they must have realised that there was a possibility of our doing so, and they had formulated a plan of campaign to meet such a contingency. We know pretty well what that campaign was. The German theory has been put into practice since; unfortunately for the Germans, it has not worked out quite in accordance with the text-books. They declared for the “war of attrition”; their idea was that, by submarine attacks, the British Fleet could be so whittled down that at length the German main Fleet would be able to meet it with reasonable prospects of success. Their Fleet, while the process of attrition was going on, was to remain sheltered in the unreachable fastnesses of the Kiel Canal. The latter, however, is the only part of the German programme which has gone according to the book.

The “High Canal Fleet” remains in the “last ditch,” and apparently, at the time of writing, seems likely to remain there. But the process of attrition has not made the progress the Germans hoped for. It is true we have lost a number of ships through submarine attacks. But it will not be overlooked by the Germans any more than by ourselves that the greater part of our losses was sustained in the early days of the submarine campaign. As soon as the Navy “got busy” with the submarine pest our losses practically ceased, and it is now a long time since we have lost a fighting unit through torpedo attack. As is usual with the Navy, our men set themselves to grapple with unfamiliar conditions, and their success has been very striking. Not only have they been able to protect themselves against submarine attack, but they have made the home seas, at any rate, too hot to hold the pirates, dozens of which have been destroyed or captured. And when the submarine war was transferred to the Mediterranean it was not very long before the Navy again had the menace well in hand. In the meantime our building programme was pushed forward at such a rate that a very large number of ships of the most powerful class have been added to the fighting units of the Fleet, with the result that not merely relatively to the Fleet of Germany, but actually in point of ships, men, and guns, our Fleet to-day is stronger than it was when war broke out. That, again, is an achievement wholly without parallel. And it is one of the chief factors in considering the future of the campaign. The Germans have never been able to rival us in speed of construction even in times of peace; it is in the last degree unlikely that they have been able to do so under the conditions that have prevailed during the past eighteen months. I have not the least doubt that we are fully justified in assuming that our final victory at sea is assured – if, indeed, it is not practically won already. The conditions are plain for everyone, both at home and abroad, to see for himself, and we have plenty of evidence to suggest that they are fully appreciated in Germany; the idle quays of Hamburg, the idle fleets of German merchant ships rotting in the shelter of neutral ports, the peaceful progress of the ships of the Allies over the seas of the world, and the growing stringency of conditions in Germany brought about by the British blockade are quite sufficient evidence for those Germans – and their number is growing – who are no longer blinded by the national megalomania.

Our Navy is a silent service; it would perhaps be better for us if at times it were a little more vocal. For there is no disguising the fact that there is a body of impatient grumblers at home who, because we do not read of a great sea victory every morning with our breakfasts, are apt to ask what the Navy is doing. We can be quite sure that that question is not asked in Germany. There, at any rate, the answer is plain.

We can discount, I am sure, the tales we hear of Germany starving, and that the horrors of Paris in 1870 are being repeated. That story is no doubt diligently spread abroad by the Germans themselves in the hope of appealing to the sentiment, or rather the sentimentality, of certain classes in the neutral nations. At the same time, we cannot shut our eyes to the growing mass of evidence which goes to show that the stringency of the British blockade is producing a great and increasing effect throughout Germany. To begin with, her export trade, despite the leaks in the blockade, has practically vanished, and it must be remembered that modern Germany is the creation of trade with overseas countries. She grew rich on commerce; she might have grown richer if she had been content with the opportunities which were as fully open to her as to the rest of the world. It is due to the steady strangling process carried out by the British Navy that her long accumulation of wealth has been decisively checked, and that she is dissipating that accumulation in what is inevitably bound to be a sure, if slow, bleeding to death. And, whatever may be the course of the War, Germany’s overseas trade can be resumed only by the permission or through the destruction of the British Navy. That is a factor of supreme and tremendous importance.

In the British blockade – in other words, in the British Fleet – we have the factor which in the long run must make possible the final overthrow of Germany. I am not suggesting that we can win this war by sea power alone; the final crash must come through the defeat of Germany’s land forces, since she is a land and not a sea Power. But it is the operation of sea power which must make the final blow possible. Sea power, and sea power alone, will make possible the final blockade of Germany by land as well as by sea. The ring of the blockade already is nearly complete; and when the British and French, advancing from the base at Salonica, link up, as they must sooner or later, with the Russian forces coming south across the Balkans, Germany will be held in a ring of iron from which she will have no means of escape.

She realises fully that she has not the remotest chance of breaking through the lines of the Allies in the West; she has failed utterly to break the Russian line in the East. It is vital for her to break the ring by which she is nearly surrounded, and in this fact we have the explanation of her dash across the Balkans. So far that dash has been attended with a great measure of success owing to the failure of the Allies to win the active support of Greece, Rumania, and Bulgaria. She has succeeded in crushing Serbia and Montenegro, and in linking up with her Turkish Allies through the medium of the Constantinople railway. But Salonica, firmly held by the Allies, must ever be a thorn in the side of her progress to the East, and until she succeeds in reducing it her flank is open to a blow which would shatter her prospects in the East as decisively as they have already been shattered in the West. We cannot imagine that the Allies have gone to Salonica solely for reasons of their health, and it needs no great acquaintance with military history to realise that the possession by the Allies of the Salonica lines may be as fatal to Germany as the holding of the lines of Torres Vedras by Wellington was fatal to the plans of Napoleon.

The analogy is not exact – analogies seldom are – but “the Spanish ulcer” is sufficiently reproduced for practical purposes. German commanders in the East can never feel safe so long as Salonica remains in our possession. And I have no doubt that when the time is ripe we shall see the Allies advancing through the Balkans to join hands with the Russians and, it may be, with the Rumanians. Then Germany will be definitely isolated, and the process of exhaustion, already considerably advanced, will proceed with ever-growing momentum, until it reaches the point when a combined attack on land by the whole of the Allies simultaneously will prove irresistible. I am not one of those who believe that Germany can be defeated by economic pressure alone. But it cannot be denied that economic pressure offers the greatest means of so weakening her power of resistance that her final military defeat will be rendered immeasurably easier.

And we must always remember – there is too strong a tendency in certain quarters to forget it – that it is the principal duty of the British Navy, so long as the German Fleet prefers idleness to fighting, to bring about the reduction of the German power of resistance by a remorseless strangulation of her trade. Our policy in this respect is perfectly definite. It is that, paying due regard to the undoubted rights of neutral nations, we will allow nothing to reach Germany which will assist to prolong her powers of resistance.

There has been a strong disposition in some quarters to represent the British Navy as fighting with one hand tied behind its back owing to the supposed apathy or worse of the Foreign Office. Sir Edward Grey, in perhaps the greatest speech of his long career, has sufficiently disposed of that charge. It is not denied that from a variety of causes, some of them at least beyond our control, Germany has obtained supplies which we would very gladly have denied to her. But, unfortunately for us and fortunately for her, neutral nations have their rights, which we are bound to respect unless we wish to make fresh enemies. It is beyond doubt that supplies are leaking into Germany through Holland and Scandinavia which we should be glad to keep out. It is absolutely impossible to prove enemy destination in all these cases, and it must be remembered that unless we can prove this we have no right to interfere with the commerce of neutral nations, who are quite entitled, if they can do so, to supply Germany with precisely the class of goods which the United States is supplying to us.

We are too apt to overlook the fact that there is nothing criminal in supplying guns and ammunition to Germany. Neutral nations are free to do so – if they can. We are entitled to stop them – also if we can. But we are not entitled to interfere with the legitimate commerce of a neutral nation; in other words, we must prove that contraband is intended for the use of the enemy before we can lay hands upon it.

It is this feature of international law which makes it so difficult for us to declare an absolute blockade of Germany. And it is just this aspect of the case which is the justification of the trade agreements of the kind which has been concluded with Denmark. Under that agreement, and under similar ones, we allow certain goods to be imported in normal volume to neutral countries under the assurance that they will not be re-exported to Germany. The agreement with Denmark has been violently attacked, and attacked, as everyone admits who has seen it, without the slightest justification. It is admitted that it does not give us all we would like to have; but, on the other hand, it is also admitted by those who have seen it that it gives us a good deal more than we could hope to obtain by other means short of what would be practically a declaration of war.

And even the hotheads among us would shrink from telling either Holland or the Scandinavian countries that unless they surrender their rights and do as we wish, we should at once declare war upon them or practically force them to declare war upon us. We need have no shadow of doubt what Germany would do if she wielded the power we do. She would show, as she has shown, scant consideration for the rights of neutrals. But, thank heaven! we are not Germany, and we fight with clean hands.

We have to solve the problem of making our blockade as effectual as possible while paying scrupulous regard to the rights of others. That problem is in process of solution; the importation of commodities into Germany is decreasing day by day; and if we are not at the end of our difficulties in this respect, we are at least drawing into sight of the achievement of our purpose. And the more fully that purpose can be attained, the nearer draws the end of the great struggle and the emancipation of the civilised world from the dominion of brute force.