As the United States possesses no island on the Atlantic side which is nearer to foreign countries than to our own, and as our interests for the immediate future lie mostly on the Atlantic side, it may be well now to apply the general principles just considered to the question of where is a naval base most urgently needed under actual conditions.
Imagining a war between us and some one European naval Power, and imagining a war also between us and two or three allied European naval Powers, and realizing the length of our Atlantic and Gulf coasts, extending from Maine to Panama, a glance at the map shows us that, apart from the home naval bases on our continental coasts, the position on American soil which is the closest to European bases is on the little island of Culebra, which occupies a salient in the northeastern end of the Caribbean Sea.[*]
[Footnote *: The acquisition by the United States of the island of Saint Thomas, about 20 miles east of Culebra, if accomplished, will extend the salient just so much farther toward Europe.]
The only reason an enemy would have for entering the Caribbean would be an intention to attack the Panama Canal region, or an intention to establish an advanced base, from which he could conduct more or less deliberate siege of our Atlantic coast and cities. In either case, our fleet would be seriously handicapped if it had no adequate base in the Caribbean; because its line of communications north would be exposed to the enemy's operations at all times; and seriously wounded American ships would have little chance of getting repairs; little chance even of making successfully the long trip to Norfolk or New York.
In case the enemy fleet should start from Europe fully prepared in every way, we should be in ignorance of its intended destination; and as the enemy fleet would be stronger than ours (otherwise it would not start) it would doubtless be able to destroy our undefended station at Guantanamo, seize some suitable place in the West Indies, say the Bay of Samana, and then establish a base there, unless we had first seized and fortified all suitable localities; and the United States would then find itself in the anomalous position of being confronted near its own coasts with an enemy fleet well based for war, while her own fleet would not be based at all. Not only would the enemy fleet be superior in power, but it would possess the strategical advantage, though far from its own shores. The situation, therefore, about a month after the foreign fleet left Europe, would be that the Caribbean Sea would contain a hostile fleet which was not only superior to ours in power, but was securely resting on a base; while ours had no base south of Norfolk, the other side of Hatteras. Our fleet would be in a position similar to that of the Russian fleet when it rushed to its destruction in Tsushirna Straits, though not in so great a degree; because it would have had more recent docking and refitting in our home ports, and the personnel would be fresher.
In case, however, we had a naval base strongly fortified and thoroughly equipped, at a salient in the Caribbean region, say at Culebra, and if our fleet were based upon it, a hostile fleet, even if it were considerably superior to our own, would hesitate to pass it and enter the Caribbean, by reason of the continuous threat that the fleet would exert on its communications. Even if the hostile fleet should pass Culebra, and establish a base farther on, an American force based on Culebra would continue to exert this threat on the communications between the hostile base and its mother country.
An American base—say at Guantanamo—would be very effective in embarrassing hostile operations west of Guantanamo, because it would be on the flank of the line of communications extending from Europe; but it would be comparatively ineffective in embarrassing operations east of it, since the hostile line of communications would be protected from it by the interposition of its own main body; this interposition necessitating the despatch of defending forces around that main body. The coming hostile force would push before it all resistance, and leave the sea free for the passage of its auxiliaries and supplies. A defending force, operating from Guantanamo, in endeavoring to prevent a hostile fleet from establishing a base to the eastward of it, would act much less effectively than a force operating from Culebra. Not only would the force from Guantanamo have to pass around the main body to attack the train; it would again have to pass around the main body to get back to Guantanamo; whereas a force operating from Culebra could make a direct attack upon the enemy's train, and then a direct retreat to Culebra.
This comparison assumes, as has been said, that the matter of resources and strength are not in question; that is, that they are equal in our two supposition bases. But, as in practice they would not be equal, the practical point to consider is how much strength and resources can compensate for inferiority of position, and how much position must be insisted on.
Of course, no correct quantitative answer can be given, except by accident. The problem, unfortunately, cannot be solved by mathematics, for the simple reason that no quantitative values can be assigned to the various factors, and because no mathematical formula now exists that expresses their relations to each other. It may be pointed out, however, that if a position be good, strength and resources can be artificially supplied; and that the cost of doing this, even on a tremendous scale, is relatively small compared to the cost of the fleet which the base will support, and in distress protect. In other words, we may be able to form an estimate of the relative values of bases, say at Guantanamo and Culebra, even if we cannot ascribe arithmetical values to each, and compare arithmetically those arithmetical values. If, for instance, we see that a fleet costing $500,000,000, would, if it operated from a base at Culebra, be 10 per cent more effective than if it operated from Guantanamo, and that it would cost $20,000,000 more to make a strong base there than to make an equally strong one at Guantanamo, we should conclude that, since 10 per cent of $500,000,000 is $50,000,000, it would be wise to spend that $20,000,000, even if we had to forego the building of one battlesbip.
We should come to the same conclusion, if we realized that no matter what their comparative values might be, a base at one place would not meet our necessities, and a base at the other place would. If a base at Guantanamo would not meet our necessities in case of an invasion of the Caribbean by a naval fleet superior to ours, then it seems idle to discuss the value of Guantanamo relative to some other place, no matter how good the position of Guantanamo may be, and no matter how nearly it may approximate to adequacy. There is no real usefulness in having a naval base anywhere, unless that naval base can accomplish the purpose for which it is desired. A naval base is desired for purposes of war, and for no other purpose whatever; and to decide on a position for a base without keeping this fact clearly in view, is to act on an underestimate of the situation, the folly of which has been pointed out in previous pages.