Thus, in theory, and to make execution perfect,—to capture, so to say, Nelson’s eleventh ship,—the aim must be to drive the enemy out of every foothold in the whole theater of war, and particularly to destroy or shut up his fleet. Having accomplished the great feature of the task by getting hold of the most decisive position, further effort must be directed towards, possibly not upon, those points which may serve him still for bases. In so doing, your fleet must not be divided, unless overwhelmingly strong, and must not extend its lines of communication beyond the power of protecting them, unless it be for a dash of limited duration. If compelled to choose between fortified ports of the enemy and his fleet, the latter will be regarded as the true objective; but a blockade of the ports, or an attack upon them, may be the surest means of bringing the ships within reach. Thus, in the War of American Independence, the siege of Gibraltar compelled the British fleet on more than one occasion to come within fighting reach of the enemy’s blockading fleet, in order to throw in supplies. That the allies did not attack, except on one occasion, does not invalidate the lesson. Corbett in his “Seven Years’ War” points out very justly, in Byng’s celebrated failure, which cost him his life, that if he had moved against the French transports, in a neighboring bay, the French admiral would have had to attack, and the result might have been more favorable to the British. Such movements are essentially blows at the communications of the enemy, and if aimed without unduly risking your own will be in thorough accord with the most assured principles of strategy. A militarily effective blockade of a base essential to the enemy will force his fleet either to fight or to abandon the theater of war. Thus, as has been pointed out elsewhere, in Suffren’s campaign in Indian Seas, so long as Trincomalee was in possession of the British, a threat at it was sure to bring them out to fight, although it was not their principal base. The abandonment of the theater of war by the navy will cause the arsenal to fall in time, through failure of resources, as Gibraltar must have fallen if the British fleet had not returned and supplied it at intervals. Such a result, however, is less complete than a victory over the enemy’s navy, which would lead to the same end, and so be a double success, ships _and_ port. 9. THE VALUE OF THE DEFENSIVE[28]