Other things being equal, the most favorable condition is that where great natural resources, joined to a good position for trade, have drawn men to settle and develop the neighboring country. Where the existing resources are purely artificial and for war, the value of the port, in so far, is inferior to that of one where the ordinary occupations of the people supply the necessary resources. To use the phraseology of our subject, a seaport that has good strategic situation and great military strength, but to which all resources must be brought from a distance, is much inferior to a similar port having a rich and developed friendly region behind it. Gibraltar and ports on small islands, like Santa Lucia and Martinique, labor under this disadvantage, as compared with ports of England, France, the United States; or even of a big island like Cuba, if the latter be developed by an industrial and commercial people. 7. STRATEGIC LINES[25] _Communications_ The most important of strategic lines are those which concern the communications. Communications dominate war. This has peculiar force on shore, because an army is immediately dependent upon supplies frequently renewed. It can endure a brief interruption much less readily than a fleet can, because ships carry the substance of communications largely in their own bottoms. So long as the fleet is able to face the enemy at sea, communications mean essentially, not geographical lines, like the roads an army has to follow, but those necessaries, supplies of which the ships cannot carry in their own hulls beyond a limited amount. These are, first, fuel; second, ammunition; last of all, food. These necessaries, owing to the facility of water transportation as compared with land, can accompany the movements of a fleet in a way impossible to the train of an army. An army train follows rather than accompanies, by roads which may be difficult and must be narrow; whereas maritime roads are easy, and inimitably wide.