From this point of view, naval bases again look much like fortresses on the land; fortresses like Metz and Strasburg, that had to be subdued before an enemy could safely pass them.

Strategic Position of Distant Bases.—­Since the strategic position of an outlying naval base is the principal factor that goes to make its value, it may be well to consider what elements make a strategic position good.

To make the problem clear, let us take a concrete case, that of our own country, and consider what elements would constitute a good strategic position for a naval base of the United States, leaving out of consideration for the moment any questions of resources and military strength.

In the case of a war with a nation that had only one naval home base, it is clear that the best position for our distant base would be one as close to the enemy’s base as possible; because, if placed there, our fleet, if it were the more powerful, could do more to injure the enemy’s fleet, or prevent its going out, than if placed at any point more distant from the enemy’s base; and if it were less powerful, it could do more to cut the enemy’s communications, because it could attack them at or near their source.

A poor position would be one far away from both countries, and far away from the line joining them.  In the case of a war between this country and Norway, for instance, a very poor position for a naval base would be a spot near—­say Juan Fernandez—­in the south Pacific.

In case the enemy country has two home bases of equal importance, the best position for our base clearly would be one equidistant from them, and as near to each as practicable.  If the distance from our base to a point half-way between the two bases is shorter than is the distance to it from either base, then a fleet at our base could probably prevent the junction of two forces issuing from those two bases—­assuming, of course, that we had a proper system of scouting.  Our fleet would be able to operate on what are often called “interior lines”—­a technical expression that has great efficacy in confusing a simple matter.  It is also assumed that our fleet is considerably stronger than either of the two separated enemy forces; otherwise our case would be hopeless.

If the two home bases of the enemy are unequal in importance, it would seem that our base should be nearer to the important base than to the other.  More strictly speaking, it should be nearer to the base from which the larger force may be expected to come out.

If the enemy country have three or more bases, from which parts of a fleet may be expected to come out, the question seems a little more complex; but nevertheless, since the first duty of our fleet would probably be to prevent junctions or a junction, of the separated parts of the enemy’s fleet, the best position for our home base would be at a point about equally distant from them all, and as close to them as possible.  In the wars between Great Britain and France in the early part of the nineteenth century, the base of the British fleet for operations on the western and northern coasts of France was as close to the enemy home bases as practicable—­though the base was England itself.  For operations on France’s southern coast, the base was at Gibraltar, or some Mediterranean island.