Take, first, the methods of securing command, by which we mean putting it out of the enemy's power to use effectually the common communications or materially to interfere with our use of them. We find the means employed were two: decision by battle, and blockade. Of the two, the first was the less frequently attainable, but it was the one the British service always preferred. It was only natural that it should be so, seeing that our normal position was one of preponderance over our enemy, and so long as the policy of preponderance is maintained, the chances are the preference will also be maintained.

But further than this, the idea seems to be rooted in the oldest traditions of the Royal Navy. As we have seen, the conviction of the sea service that war is primarily a question of battles, and that battles once joined on anything like equal terms must be pressed to the last gasp, is one that has had nothing to learn from more recent continental discoveries. The Cromwellian admirals handed down to us the memory of battles lasting three, and even four, days. Their creed is enshrined in the robust article of war under which Byng and Calder were condemned; and in the apotheosis of Nelson the service has deified the battle idea.

It is true there were periods when the idea seemed to have lost its colour, but nevertheless it is so firmly embedded in the British conception of naval warfare, that there would be nothing left to say but for the unavoidable modification with which we have to temper the doctrine of overthrow. "Use that means," said its best-known advocate, "when you can and when you must." Devoutly as we may hold the battle faith, it is not always possible or wise to act upon it. If we are strong, we press to the issue of battle when we can. If we are weak, we do not accept the issue unless we must. If circumstances are advantageous to us, we are not always able to effect a decision; and if they are disadvantageous, we are not always obliged to fight. Hence we find the apparently simple doctrine of the battle was almost always entangled in two of the most difficult problems that beset our old admirals. The most thorny questions they had to decide were these. In the normal case of strength, it was not how to defeat the enemy, but how to bring him to action; and in casual cases of temporary weakness, it was not how to sell your life dearly, but how to maintain the fleet actively on the defensive so as at once to deny the enemy the decision he sought and to prevent his attaining his ulterior object.

From these considerations it follows that we are able to group all naval operations in some such way as this. Firstly, on the only assumption we can permit ourselves, namely, that we start with a preponderance of force or advantage, we adopt methods for securing command. These methods, again, fall under two heads. Firstly, there are operations for securing a decision by battle, under which head, as has been explained, we shall be chiefly concerned with methods of bringing an unwilling enemy to action, and with the value to that end of the maxim of "Seeking out the enemy's fleet."

Secondly, there are the operations which become necessary when no decision is obtainable and our war plan demands the immediate control of communications. Under this head it will be convenient to treat all forms of blockade, whether military or commercial, although, as we shall see, certain forms of military, and even commercial, blockade are primarily concerned with forcing the enemy to a decision.

Our second main group covers operations to which we have to resort when our relative strength is not adequate for either class of operations to secure command. In these conditions we have to content ourselves with endeavouring to hold the command in dispute; that is, we endeavour by active defensive operations to prevent the enemy either securing or exercising control for the objects he has in view. Such are the operations which are connoted by the true conception of "A fleet in being." Under this head also should fall those new forms of minor counter-attack which have entered the field of strategy since the introduction of the mobile torpedo and offensive mining.

In the third main group we have to deal with the methods of exercising control of passage and communication. These operations vary in character according to the several purposes for which the control is desired, and they will be found to take one of three general forms. Firstly, the control of the lines of passage of an invading army; secondly, the control of trade routes and trade terminals for the attack and defence of commerce; and thirdly, the control of passage and communication for our own oversea expeditions, and the control of their objective area for the active support of their operations.

For clearness we may summarise the whole in tabulated analysis, thus:—

1. Methods of securing command: