In his book, published in 1911, entitled Some Principles of Maritime Strategy, Corbett defines the battle fleet as the agent for securing command of the sea communications, otherwise known as “command of the sea,” and cruisers as the agents for exercising such control or command. He also observes
. . . the more numerous and better adapted they (cruisers) are for preying on commerce and transports, the weaker will be their individual fighting power.
The necessity of following up a victory at sea by exercising the command thus secured and the great economic pressure which the destruction of its commerce puts upon a maritime nation were probably well recognized by the various European delegations to the Washington conference in 1921 and may well have been the underlying cause for the failure to limit cruisers then.
Certainly after the war there was a tremendous amount of shipbuilding to meet expanding world trade. There was also a great deal of cruiser construction. The United States was conspicuous by its abstention from both. It was perhaps just as well that we did not attempt to build ships for the carrying of our rapidly increasing trade until the race to build commerce destroyers by other nations was halted. That having been more or less satisfactorily accomplished at London, we are now launched upon a shipbuilding program that is causing increasing economic pangs in shipping circles abroad.
The two limitation conferences have unquestionably affected the degree to which the maritime powers can exercise command of the sea, in that warship types adapted to commerce destruction have been definitely limited. Among these types the cruiser stands out as the most dangerous to commerce.
In the decade before the World War, the battle cruiser and high-speed battleship had made the armored cruiser obsolete. There was a definite trend toward the small light cruiser of weak individual fighting power but with sufficient speed to overhaul the fastest merchant ships. The prewar German Emdens were typical examples. Against unarmed merchant ships they were the cheapest and most effective type. With the mounting of 5- and 6 inch guns on merchantmen they became outgunned by their normal prey and the 6- inch-gun cruiser was evolved to take their place.
The demand for speed now began to make cruisers too expensive for quantity production, an essential to an effective commerce destruction force. The “sloop” was evolved as a concession to the original cruiser idea. Meanwhile designers began a race for bigger and better 6-inch-gun cruisers.
The results of naval actions of the war seemed to indicate that a heavy and fast light cruiser and a very fast and heavy battle cruiser were the correct types for future cruiser construction. The cruiser submarine made its appearance. The value of volume of gunfire in support of destroyer attacks had its effect on cruiser design. The armored cruiser with its heavy guns was definitely discarded, as being too slow to catch the light cruiser and too weak to stand up to the battle cruiser. The battle at the Falklands demonstrated the power of the battle cruiser, the hopeless plight of the armored cruiser, and the chance the light cruiser had of escaping. The battle of Jutland demonstrated the ability of the German battle cruisers to take heavy punishment, the inability of the armored cruisers to influence the outcome of the battle, and the ubiquitous success of the light cruiser.
Consequently we find Great Britain building a Hood, the United States building six huge Lexingtons, and Japan embarking on the eight-eight program of battleships and battle cruisers. Great Britain began building the County class of light cruisers and the United States the Omaha class. France, Spain, Italy, Holland, and other minor naval powers began building fast light cruisers with 6-inch guns.
Naval attention everywhere was preoccupied with battle cruisers and light cruisers. Then suddenly the British Admiralty discovered that it could not afford to go on with the naval race for supremacy, nor could it afford to stop if others went on. The light cruiser and the battle cruiser were making a joke of national budgets.
The Washington conference upset all previous calculations by practically eliminating the battle cruiser from future consideration and by creating the 10,000-ton cruiser carrying 8-inch guns—a type no navy could subsequently afford to be without and yet one for which war experience provided no justification as far as European navies were concerned. Our own cruiser needs are somewhat different.
If Corbett’s definition of a cruiser is correct these ships are not cruisers, for, with their 8-inch guns, they are distinctly fighting units. As a means of preying on commerce, they are individually no more effective than the true 6-inch-gun light cruiser except for their greater cruising radius. As a means of breaking up torpedo attacks on the battle line they are less effective than 6-inch-gun cruisers. As scouts they possess no more eyes. As a fleet type they are abnormal. They are essentially destroyers of commerce destroyers.
Just as the torpedo-boat menace was met by the torpedo-boat destroyer, the cruiser menace to commerce appears to have been met by the cruiser destoyer appearing, under the arbitrary characteristics of the Washington agreement, as of 10,000 tons and carrying 8-inch guns. The only excuse for unarmored 10,000-ton cruisers carrying 8-inch guns is to destroy cruisers carrying 6-inch guns, which are operating on trade routes. They do relieve the fleet of this duty and, if so employed, increase its mobility and freedom of action. If this be their true function, it should divorce them from fleet operations of a tactical character. The fleet must still be supplied with ships capable of providing it with the service of information and security for we still need scouts and defense against torpedo attack.
The more true light cruisers mounting flinch guns our enemy has operating against commerce, the smaller the number of heavy cruisers we can withdraw from the protection of commerce for duty with our own fleet. When we limit the number of cruisers in our Navy we sacrifice either security for our fleet or security for our commerce. We cannot have both if the enemy has a greater number of cruisers than we have, especially of the light cruiser type. This consideration has affected British naval needs. For every light cruiser operating on trade routes there should be a cruiser destroyer on its trail for effective protection of commerce and communications. Fifteen heavy cruisers will not go far nor would twenty-five be sufficient against a navy with “parity” in fighting strength. The fast armed merchant cruiser makes it impossible to fix any number of cruiser destroyers as adequate.
As though in recognition of the inadequacy of the treaty cruiser, through lack of sufficient number ever to be equal to the full protection of trade routes, the speed of this type has been reduced to a point lower than that of many of the light cruisers presumably their prey. The speed it should have to fulfill its true function has been put into gun power and “life” which will permit it to give a good deal and to take some punishment. We have robbed Peter to pay Paul and have succeeded in creating a hybrid that is neither able to run down the 33-knot light cruiser nor to survive contact with a battle line. They cannot long survive contact with each other.
One class alone in foreign navies seems to be actually at their mercy—aircraft carriers. They can run down and out-gun any such except the Japanese Akagi, though their arbitrary life is less. The power that they have of destroying carriers indicates that they should be so used in fleet operations which, in turn, will force an enemy to give his carriers heavy escort, thus weakening his fleet or limiting the mobility of his air force.
We thus see that the heavy cruiser is not a cruiser in the sense that it is an agent for the exercise of command of the sea, but is a fighting agent for depriving others of such command. We must look to other agents less limited in numbers for the exercise of command. We are permitted to have an inadequate number of light cruisers carrying 6-inch guns for this purpose, inadequate because of the tonnage put into treaty cruisers. We have no network of bases supporting each other along the world’s main trade routes to increase the mobility and efficiency of cruisers, such as England has. Consequently our light cruisers must have long fuel endurance which means that they must have a comparatively large displacement, which in turn means fewer cruisers under a total tonnage limitation. Where England can use 6,500- ton cruisers efficiently, we need 9,000-tonners or larger solely through lack of spaced fueling bases along the main trade routes. Therefore they might just as well carry 8-inch guns but this they may not do.
Command of the sea cannot of course be exercised until it is secured through the defeat or immobilization of the enemy fleet. Should this be accomplished, there would probably be released sufficient cruisers, light and heavy, to exercise command, provided defeat of the enemy fleet did not all but destroy our own. Certainly cruisers will suffer heavily in a fleet action. Should such be the case and the enemy possess a large merchant marine, we might find ourselves with a badly crippled navy unable to exercise the command which would follow a victory.
While the objective of a fleet in war is properly the enemy fleet, the object for which the war is fought will not necessarily be obtained by victory in a fleet action which may or may not secure command of the sea. Command of the sea must be exercised if pressure sufficient to force peace is to be placed on the enemy. Naval forces are but the instruments in naval operations designed to create this pressure. The pressure being economic, involving the isolation of the enemy from supplies of food and raw materials, it is directed primarily against shipping and, therefore, does not require the use of heavily armed ships, but rather of fast ships.
With the defeat of the enemy fleet, the 8-inch-gun cruiser is released for its primary purpose of cruiser destroying and general protection of trade routes from which it can be driven only by the battle cruiser. Its chance of survival in a fleet action, however, is small.
The existence of each type of warship, carrying its own special menace, forces upon navies a countertype. With the possible exception of the new German Deutschland there is no countertype for the treaty cruiser except the battle cruiser, and of these there exist only seven in the world as against ten times as many treaty cruisers. Under the circumstances, since the treaty cruiser has apparently come to stay, the indications are that the battleship, if replaced at all, will be partially replaced by a battle-cruiser type.
As the present enormous battle cruisers are far more powerful than necessary for treaty-cruiser destroyers and as they are definitely conceded to be obsolete as battle line ships, we may expect that proposals to replace one 35,000-ton capital ship by two small battle units will be advanced. This will result in the gradual elimination of the great battleships of present-day navies.
Since, however, the heavily armored ship is, in the last analysis, the backbone of naval power, we may expect that this type will be retained in some form. It is possible that in replacing one large battleship with two smaller ships of the same aggregate tonnage, we may find it appropriate to construct one with speed at the expense of armor protection and the other with armor at the expense of speed, thus maintaining an armored battle line of smaller units and adding a countertype to the treaty cruiser. The general effect would be to reduce the individual tonnage of warships to around 16,000 tons as a maximum and, probably, to reduce the heavy guns to about 13 inches or less. International agreement would, of course, be necessary.
What would be the characteristics of these new types? The fast type would probably carry four to six heavy guns and be capable of 34 knots or more. For destroying treaty cruisers, a gun of 10-inch caliber would be sufficient, but would make them forever fugitives from true battleships. Perhaps a two-gun turret of 10-inch guns forward for chasing treaty cruisers and a twin turret of 12- or 13-inch guns aft for standing off battleships would be feasible.
The 16,000-ton battleship could probably not mount over six 12- or 13-inch guns with full armor protection and still be capable of a 21-knot speed and a 10,000-mile radius.
Should all present battleships be so replaced, we would still have fifteen battleships and in addition have fifteen heavy cruisers to take care of the fifteen treaty cruisers in the British fleet. It is probable that the cruising radius of these new types would not be as great as that of the present large battleships, which would tend to weaken our position somewhat in the Pacific where there seems to be little to fear. Treaties have disposed of immediate danger and economic forces tend to discourage belligerency.
Should such types be accepted, we should then have in our Navy
15 | 16,000-ton, 21-knot battleships, |
15 | 16,000-ton, 33-knot super-cruisers, |
18 | 10,000-ton, 32.5-knot treaty cruisers, |
23 | 7,500-ton, 33-knot light cruisers. |
This is an increase from the present built, building, or authorized of from forty-three to seventy-one units, provided we built up to our parity allowance.
It has been pointed out that plane carriers, except for the American Lexingtons and the Japanese Akagi, are out-gunned by the treaty cruiser. This gun power of the treaty cruiser must necessarily affect the characteristics of carriers laid down in the future. They must carry 8-inch guns and have either great speed or superior life to cope with the treaty cruiser.
Aircraft carriers are limited to 27,000 tons and to 8-inch guns for those laid down or acquired in the future. While there is a demand for more numerous carriers, small carriers must sacrifice speed or life and cruising radius, if they are to be able to defend themselves against treaty cruisers. If they are lightly armed and armored they must be escorted and the more there are, the more ships must be drawn from fleet service to escort them or they must remain with the fleet and thereby hamper it. It would appear that carriers should be strongly armed, well-protected ships, if they are to provide the best opportunities for the planes they carry. This can certainly be done within the tonnage limits, probably about 20,000 tons, which would permit construction of three more. These would, of course, be augmented in time of war by converted liners.
The destroyer type has also been affected by the treaty cruiser which has reached a size and gun power that makes it a legitimate torpedo target. Post-war destroyers are larger and faster than ever, and the tendency is toward larger and longer range torpedoes. There are “leaders” in foreign navies reported to have made over 40 knots on acceptance trials. Unsupported destroyers must have the speed to escape from fast light cruisers. There is little doubt that destroyer types of the immediate future will include one having a speed of 40 knots and a displacement of around 1,800 tons—in effect a torpedo cruiser. This will be necessary if the torpedo is to retain its present menace against fighting ships, among which must be included the treaty cruiser.
The present tendency toward speed in surface ships makes the submarine less and less satisfactory as a tactical weapon. This is reflected in the drastic tonnage cut at the London conference and in allowing Japan parity. The more navies are limited the less they can afford to indulge in submarines. A low global limitation would probably have the ultimate effect of eliminating the coastal submarine from the major navies and reducing the number of fleet submarines to a minimum. Mine-laying submarines will always be found useful.
The treaty cruiser as a cruiser destroyer has greatly limited the effectiveness of the armed merchant cruiser which has generally less speed and gun power than the light cruiser. This may account for the very evident dislike the British have for treaty cruisers in other navies and their great desire to see them strictly limited, especially in the Mediterranean and in the Far East.
The process of adjustment of navies to the treaty cruiser is going to be a long and expensive one, a result altogether out of accord with the spirit in which the Washington conference was conceived. The framers of the limitation treaty had apparently no idea that in placing a limit on certain characteristics they were forcing upon navies a new type, the effect of which would be to increase naval expenditure all along the line. We feel that we must have these cruisers because they are the biggest and most powerful ships allowed in their class and because others have them. There is reason to doubt that the class is so valuable to naval operations as to warrant tying up much tonnage and money in them. There is this to be said for them. They are essentially defensive in character and indicate a non-aggressive policy of the nations to which they belong, in that they tie up cruiser tonnage which otherwise could be put into types especially adapted to commerce destruction. They do limit the power of any one nation to exercise command of the sea and, if kept in reserve during a fleet action might rob this action of its real value, which is, of course, the exposure of an enemy’s commerce and communications to unhindered attack.
Whether a countertype will be evolved or whether the treaty cruiser will become obsolete in its turn twenty years from now remains to be tested. In our own Navy we have under consideration another hybrid type, the cruiser carrier, a light cruiser mounting eight 6-inch guns and equipped with a flying deck from which a flight of planes may be launched and upon which surviving planes may be received. By the London treaty 25 per cent of 6-inch-gun cruiser tonnage may be so constructed. Under certain circumstances in which the planes can be used, such a cruiser is more than a match for an 8-inch-gun cruiser. In good weather it is a superscout with a greatly extended range of vision. These same qualities make it a great menace to commerce. Its weaknesses are light protection, moderate gun power, and vulnerability of its flying deck. On the whole it is theoretically the best cruiser type for all- around service which has been conceived and one which the treaty cruiser must respect whenever flying conditions are favorable. A treaty cruiser which attempted to drive a cruiser carrier off a trade route might find itself engaged with a hornet’s nest from which there was no escape.
Is it also possible to develop the regular 6-inch-gun cruiser into a fast heavily gunned ship which can close a treaty cruiser with its speed, and overcome it through sheer volume of fire. A 6-inch-gun cruiser with the same number of guns can deliver from two to three times the number of shots per minute as can an 8-inch-gun cruiser. At ranges where 6-inch can penetrate, the 6-inch cruiser will inflict the greater damage and should survive a short hot action. No treaty cruiser could long stand up against a 6-inch-gun cruiser with nine to twelve guns under such circumstances.
Treaty cruisers have the “punch” with their 8-inch guns, but they are under the necessity of continually “pulling it” by having to remain outside the penetrative range of their opponents, which means that they have to stay on the fringes of the battle or run the chance of quick and complete destruction. They must watch as anxiously as any battleship for torpedoes. They haven’t the volume of fire to stop a determined torpedo attack. They do not fulfill a battle function of the fleet.
Their role seems to be stiffening an advanced scouting line of weaker ships such as light cruisers, destroyers, or merchant scouts; attacking carriers in unfavorable flying weather; and chasing light cruisers off trade routes provided they do not get chased themselves by light cruisers able and anxious to fight and close the range.
The 35,000-ton battleship is passing. No one thinks of building any more. Everywhere there is the inclination to extend their “life” and in some quarters, to reduce the size of any to be built. Each conference sees the battle line reduced by a few more leviathans. Why? They cost too much for the naval return they give and it takes a swarm of light craft to get them safely into action. They have a habit of limping home from action. If there is anything more like the proverbial white elephant, than a badly damaged battleship at sea, it is two of them. They are indispensable, however, if an enemy has them and, for that reason, we may expect to see them as over-aged veterans in a future war, either sulking at anchor or putting to sea with as many screens as a seven-veiled dancer. Veils do not stand rough treatment. Neither do screens in a fleet action. With limited navies it is scarcely good strategy to risk a fleet action with all available naval forces, for the cost of victory might be so great that we can, after all, exert no great economic pressure on our enemy.
Perhaps it is just as well that we have some cruisers which it would be suicidal to bring into a fleet action and which are thus the nucleus of a naval force after the action. Having had a good, hard, satisfying battle in the traditional Nelsonian manner we could then get down to the important business of starving an enemy people into submission through relentless war on his commerce.
England has six 8-inch-gun cruisers on over-seas commerce protection work at present and intends to add at least two more, leaving but six in the Altantic with the fleet. One seems to have a roving commission. This looks like a proper appreciation of the treaty cruiser’s role.