Prior to the tests of the atomic bomb on naval and merchant shipping at Bikini Atoll, there was widespread speculation on the ability of vessels to withstand the cataclysmic explosion of the splitting atom, and on the effect that the bomb would have on navies and on sea power. While complete results of the two tests so far held—a third was scheduled for early 1947—have not yet been determined, and probably will not be for months because of the difficulty of correlating all the data, certain effects seem established. Among these are: one atomic bomb detonated in the air or in the water will do infinitely greater damage than any other known explosive; the radioactivity continues dangerous longer when the atom is split under water than when it is split in the air; the radius of damage is rather less than was at first thought, as vessels moored more than a mile from the center of both explosions suffered relatively light injury; the armor of warships stood up well under the blast effect, but delicate and all-important equipment such as radar and fire control instruments suffered severely. Until scientists and naval designers have had time to coordinate, study, and evaluate their findings, it will be impossible to assess accurately the total effect that atomic weapons will have on war at sea. Even so, at least three conclusions appear inescapable from the information now available. These are: scientists are faced with the problem of protecting crews against the lethal effect of radioactivity; naval designers must give increased protection to radar and fire control equipment; and aircraft are vulnerable to the blast even when it occurs under water and when the planes are high above it. One plane was damaged when flying six thousand feet above the second bomb burst and another suffered damage at sixteen thousand feet.
Two great perils have arisen as a result of the tests. These dangers curiously enough are directly contradictory. The first is that the power and the lethal effect of atomic bombs will be underrated; the second is that in drawing certain conclusions from the tests, the effect of the bomb will be overrated. Because of the high death toll and widespread destruction caused by the two missiles dropped on Hiroshima and Nagasaki, a large proportion of the people of the United States confidently expected that the entire target fleet at Bikini would be sent to the bottom at the first blast. That so few of the ships were sunk, even by two blasts, has led many people to believe that atomic fission is not so powerful as they had at first feared and that they need worry no more about it. (Among other things, they fail to take into account the fact that warships are built to withstand shocks and explosions, and that cities are not.) This is a most dangerous fallacy, but one with which this article is not concerned. There is another large group of people—and these the most vociferous—who will continue to point out that even if the two bombs failed to destroy all the ships in Bikini lagoon they did infinitely more damage than any two other bombs ever did to vessels, and that had a half a dozen or a dozen bombs been used the entire fleet would have been destroyed. This is no doubt true, but the conclusion drawn from this argument is false. They reason—as they were doing before the tests were made—that navies are superfluous because atomic bombs will sink ships with ease, and that therefore sea power can be eliminated as a factor in future wars. The atomic bomb, they contend, marks the complete triumph of air power as the sole manifestation of the military might of a nation. Fortunately this opinion is not universally held, because however great the final effect of the atomic bomb will prove to be on the theory and practice of naval construction, its effect on sea power will be so slight as to be negligible, whereas its effect on military aviation may well prove disastrous.
Every time a new naval weapon, or one with naval capabilities, makes its appearance, it is hailed as heralding the end of sea power. “This new device rings the death knell of navies,” “Sea power is rendered obsolete by this terrible new invention,” “this new engine of destruction marks the end of naval power,” “from now on sea power will no longer count,” “why waste millions on warships when thousands spent on this new invention will do the same job and do it better?” are some of the opinions invariably following the announcement of each lethal discovery or new machine of war which can be employed below, on, or above the sea. When cannon were first placed on galleys and put an end to the oar-propelled ram, a large and voluble group of “experts,” no doubt, announced the end of war at sea. Sea power became a thing of the past when Mr. Whitehead" produced the automotive torpedo. Sea power was doomed when Mr. Holland perfected the submarine. Sea power ceased to exist with the advent of the airplane. And now, it appears, sea power, which somehow not only managed to survive these other horrendous and indefensible weapons but also managed to increase its influence, is doomed once more. This time it is the atomic bomb that will doom it.
No one conversant with naval history will contend even briefly that these and other inventions, developments, and discoveries have not had an effect, a very marked effect some of them, on war at sea. Cannon, which compelled the change from oar to sail greatly expanded the influence of sea power, as later did the gradual substitution of steam for sail. The application of the explosive shell to naval ordnance, instead of putting an end to warships, made such craft more powerful and stronger defensively by causing the development of armor. The effects of the torpedo were even more marked, but not in the way its advocates predicted. It is not too much to say that Mr. Whitehead indirectly won World War II for the United Nations, although he furnished the Central Powers with their most dangerous single weapon in World War I.
The torpedo has probably had a more profound and far-reaching effect on naval warfare than any other one weapon since the discovery of gunpowder. Hailed as a device that would make small navies the equal of large ones and the machine that would alter the entire complexion of sea power, the automotive torpedo produced two new types of warships and made successful a third type which up to that time had not proved effective. It gave birth to the torpedo boat and the torpedo boat destroyer, and it made the submarine efficient and deadly. Yet it was the destroyer—developed as the “answer” to the torpedo boat—which chiefly defeated the submarine when that new weapon was used so proficiently by Germany from 1914 to 1918. Designed primarily to hunt down and sink torpedo boats and to protect the large vessels of the fleet from torpedo attack, the destroyer became such a versatile weapon that it was adapted not only to defend against the submarine and to sink the latter, but has become a most capable antiaircraft escort vessel. The torpedo, moreover, brought about the fitting of bulges to capital ships to protect them against underwater explosions, thus providing no inconsiderable protection from bombs exploded alongside.
The airplane, heralded in many quarters since the end of World War las the final blow to sea power, the one weapon which surely and finally would write finis to navies, has become one of the most potent weapons in the arsenal of sea power. Perhaps even more than the destroyer, the airplane helped keep the sea lanes open to United Nations’ commerce, troopships, and supply vessels against the constant and skillful attack of Nazi undersea fleets. Instead of eliminating warships, as many of its proponents claimed it would do, or even ending the reign of the capital ship as the backbone of naval power, the plane introduced into war at sea an entirely new capital ship, the aircraft carrier, which with, and not in lieu of, the battleship makes up the chief striking force of modern navies. It is a matter of record that during the first year of the war in the Pacific, the Japanese controlled the ocean from their own shores almost to Midway. And this control was exercised not alone by aircraft and by carriers but by all the ships which made up their fleets. At Midway the Japanese were turned back by aircraft, but by aircraft largely from carriers. In spite of Japanese losses there, however, the United States Navy was still too weak in battleships to take immediate advantage of the enemy’s defeat. The United States was unable to make headway in the eastern reaches of the Pacific until the damage and loss suffered at Pearl Harbor had been repaired and replaced, and American cruisers, destroyers, and carriers could be supported by the heavy guns of battleships.
Navies and sea power survived the air plane, they survived the parachute bomb, they survived the aerial torpedo, the glide bomb, and the robot bomb just as they survived cannon, shells, torpedoes, and submarines. All and each of these weapons sank ships, wrought great destruction, and at times made life aboard vessels of war highly unpleasant. But from each test, navies and sea power have emerged stronger and more important than they were before, as the history of the conflict just ended helps demonstrate. Navies have altered in organization, in types of vessels and in tactics, but they have remained one of the basic forces for carrying out the will and policies of nations. Since the beginning of war at sea, sea power, except in the engines of its application, has not altered from the doctrine expounded by Admiral Alfred Thayer Mahan. Regardless of the final results of the Bikini tests, or of the destruction at Hiroshima, and at Nagasaki, the effect of the atomic bomb on sea power will be little greater than was the effect of the explosive shell. Here, however, one must make a very important distinction. While the bomb itself will bring little change in the conception of sea power, the ability to control and use atomic energy will probably have a most profound effect on that conception. Before amplifying these statements, it is essential to do two things: examine more closely the potentialities of the atomic bomb, and define sea power. It is in misconceptions of this term that much of the opinion on naval matters has gone astray.
Basically the atomic bomb is a combined high explosive and incendiary. Scientists appear divided about the radio-active effects of its explosion. There are other points on which the scientists are divided, but for the purposes of this article the essential facts are that the bomb combines the qualities of a demolition and an incendiary, and is approximately twenty thousand times more powerful than any other missile hitherto constructed. Not only does it explode with immeasurable concussion and blast effect, thereby creating a fiercely destructive vacuum, but also its flash is so terrifically hot that it fuses metal into dust and acts as an incinerator of seemingly unlimited temperature. These powers make the atomic, bomb a frightful and in sober truth a world shattering weapon of destruction. They also make it a bombardier’s dream. He no longer has to hit his target, he does not have to come within a thousand yards of hitting it. The famous Norden bombsight is thus rendered as obsolete as the crossbow. The Liberator, the Flying Fortress, the Superfort, designed to fight their way in daylight to the target, and then to destroy with great precision the military objective and leave unharmed the cultural monument or the hospital a hundred yards away, may now take their places with Old Ironsides and Nelson’s Victory as relics of a glorious past. The atomic bomb needs no mass air fleets to flatten a city, it needs no swift, heavily armed and armored bomber to carry it. As a matter of fact it needs no plane at all. It can be propelled by rocket, and directed by radio. True, it may miss the exact target, but that is of scant consequence for it will destroy everything within a mile radius. The bomb is not selective; it will blast the military objectives and everything else.
These qualities of widespread destructiveness represent weakness as well as strength. They put definite limits on the utility of the bomb. The United States could not, for example, have employed the bomb against the Japanese forces in China, Malaya, or Burma, or against the Germans in any of the occupied countries of Europe. Like rain, the effects of atomic fission fall equally on the just and on the unjust. The bomb kills Americans, Chinese, Danes, Dutchmen, Englishmen, Esquimaux, Frenchmen, Norwegians, and Poles with the same fine impartiality as it kills Germans and Japanese. It cannot distinguish between an ammunition dump and a cathedral, between a gun emplacement and a library, between an airfield and a hospital; and more important, the man who drops it is similarly unable to make such discriminations. If an orphanage is within a mile of a ball bearing plant, they both vanish in the same cloud of smoke and dust. The user of the atomic bomb must cease talking about military objectives. No room exists for such fine distinctions. The enemy, all the enemy, is the enemy. There is no degree of enmity. The atomic bomb is total war in the fullest sense of the word. Hence its use on land is limited. At sea, such limitations apparently are not in force, because in the normal course of modern naval warfare, friendly and hostile vessels seldom are close enough to be affected by the same bomb except in small craft encounters, when the atomic bomb would hardly be used in any case.
From the foregoing it would seem at first glance that the atomic bomb would indeed put an end to navies and to sea power. That would be a superficial view. If the two Bikini bombs had destroyed every battleship, aircraft carrier, cruiser, destroyer, landing craft, and merchantman in the lagoon so that no vestige remained, the only result would be to prove again what everyone knows: if enough explosive force is applied, it is possible to sink or otherwise destroy vessels. As a matter of fact, the tests are useful only because destruction was not complete, but permits examination of the hulls, superstructure, armor, and other parts of most of the target ships. Here, in the field of naval architecture, would appear to lie the chief value of conducting the experiment. For in this field the explosive effects of atom splitting were not certain before the tests were conducted; what was and is certain is that navies will continue in being, although altered in appearance, and that the doctrine of sea power will remain essentially unchanged.
Sea power is a theory. It is a principle of war. Theories can no more be destroyed by bombs than ghosts can be destroyed by bullets, or than a proposition of Euclid can be destroyed by a battery of field artillery. Theories can be destroyed only by the discovery of flaws in the reasoning behind them, or by the establishment of pertinent facts not previously known. There can be no contention that the atomic bomb is a flaw in the reasoning of Mahan. The atomic bomb is certainly a fact, and one not known when the doctrine of sea power was propounded, but its pertinency as an invalidator of the principles advanced by Mahan is by no means clear. If the destruction of a battleship or a whole fleet of battleships could have disproved the theory of sea power, the theory would long since have ceased to exist. It would, indeed, have died at Pearl Harbor. Sea power is not battleships, and cruisers, and destroyers, and aircraft carriers, and submarines. Sea power is not the sum of these things. They represent only part of the method by which the doctrine of sea power is carried into effect; they represent the force necessary to apply sea power. Warships, by defeating the enemy’s naval forces, or blockading them in their own ports, achieve command of the sea, they open the sea lanes to friendly merchant shipping so that troops, ammunition, food, weapons, and all the other impedimenta of war may be moved from one place to another. Without merchant shipping there is no sea power. Without bases from which the fleet can operate to open the sea lanes and keep them open, there is no sea power. Without ports and harbors from which merchant shipping can load or to which they can carry their cargoes, there is no sea power. Without men trained in all the arts that go to make up the shipping industry in all its branches, there is no sea power. All these things must exist at the same time, or there is no sea power. It is unnecessary to trace in detail the ebb and flow of the fortunes of war in the Pacific to demonstrate this thesis. With the United States battle fleet immobilized by the Pearl Harbor attack, Japan had complete control of the Pacific theatre of war. Using her carriers, she had destroyed the effectiveness of her enemy’s navy and had achieved that command of the sea which is the first requisite of the application of sea power. Then using her battleships, carriers, and other war vessels to sweep aside hostile light forces still in the area, she kept the sea lanes open, and with her cargo vessels and transports moved her expeditions to the Philippines, Wake Island, Guam, Malaya, Borneo, New Guinea, and the Aleutians. Until the United States could recover from the damage initially inflicted, make good her losses, and provide sufficient heavy ships to challenge Japanese supremacy in battleships and carriers, Japanese success was almost universal. Once American naval strength had been built up, bases had been established, and the merchant shipping constructed to transport supplies and troops, Japanese advances were checked. Gradually control of the sea was wrested from the Japanese, and as American sea power—represented by warships, bases, and cargo carriers—replaced Japanese sea power, the latter’s military forces suffered reverse after reverse. Cut off from supplies and reinforcements, called upon to meet attacks from an enemy who by reason of his sea power could strike when and where he chose, the Japanese army was almost powerless to affect the progress of the war. The end could be delayed, but the end was inevitable once Japanese sea power was broken. When her transports and supply vessels were sunk or driven from the sea, Japan was defeated. When Japan lost command of the sea and that command passed into the hands of the United States, the issue was no longer in doubt.
Command of the sea was not taken from the Japanese by battleships, carriers, cruisers, destroyers, and other surface forces alone. To an extent not yet generally known, but to a very large extent, this command was achieved by submarines. To an extent widely publicized, and also to a considerable extent, this command was achieved by military and naval aviation. But any weapon whether it is a battleship, a submarine, a mine, an airplane, a depth charge, or a duck, which effects control of the sea lanes, which prevents hostile forces from using them, or protects friendly vessels, is part of sea power. Sea power may be said to have two sides, a positive and a negative. The latter is composed of warships, planes, any weapon which destroys enemy forces and shipping and thus denies him the sea. These same weapons also are part of the positive side, for they protect friendly shipping which uses the ocean highways. But the positive side also includes that friendly shipping, for without it there would be no sea power. One aspect of sea power is destructive, one is constructive. One tears down the enemy’s strength, the other builds up friendly forces. How the enemy strength is tom down, what the weapons used to sink his ships, to blockade his harbors, to prevent his using the sea lanes, to render him powerless to interfere with friendly use of the sea, is a matter of little consequence. Whatever the weapon may be, it is part of sea power if it acts to guard the transports and supply ships of one antagonist and attack those of the other.
The atomic bomb, therefore, cannot operate to destroy sea power; it can, by destroying enemy shipping, both naval and merchant, aid in the negative phase of applying sea power. But the atomic bomb cannot take part in the positive phase. It cannot transport cargo, or troops. It cannot use the sea lanes to move men and munitions. Atomic energy, once it has been controlled constructively, may and probably will be applied to this end. Atomic energy used in ships, or in aircraft as motive power, or in some way not yet even conceived may well permit the transportation of cargo in completely new ways. Once that is done, sea power ceases to exist. It becomes obsolete, just as obsolete as it would become if all commerce were carried by aircraft and none by water. New methods of transportation, new lines of communication, will result in new theories of protection and new methods of interfering with hostile use of that transportation and those lines of communication. The theory of sea power will then be invalid, or rather will be supplanted by new theories based on the establishment of new facts. Those methods are not yet at hand. Until they are, sea power will remain a factor in any future conflict. The atomic bomb, while it will aid in the application of sea power just as any other weapon aids, cannot destroy sea power or even alter its conception because the atomic bomb cannot replace commerce at sea.
It is not at all certain that the atomic bomb will destroy the usefulness of naval vessels or have a marked effect on the organization of navies. It may well develop, indeed, that the atomic bomb is more likely to put an end to military and naval aircraft than it is to put an end to navies. The warship-warplane controversy, which began shortly after the close of World War I and is still, like the heathen, “so furiously raging” and to as little purpose, had little or nothing to do with sea power, although the term was loosely used on both sides as a synonym— which it is not—for naval force. Actually one side was contending that ships alone could protect commerce, or that ships were essential even though planes might assist. The other side argued that commerce could be better protected by planes, that warships could be destroyed easily by planes with little loss to the latter, and that ships were therefore, both expensive and unnecessary. The real fight was not over the effect of aircraft on sea power, it was a row over whether planes could sink warships. The sea people argued that ships presented highly mobile, relatively small targets, and could be hit with bombs only when the bombers attacked at low altitudes, and that ships’ antiaircraft fire would knock the planes out of the sky before they could drop their bombs. Modern warship construction, the sea people said, rendered the heavy ships of a fleet nearly unsinkable by bombs even if hit. The air people denied that low altitude attacks were necessary to record hits, contended that planes traveled too fast to be bothered by anti-aircraft fire, and clinched their side of the case by stating that it was impossible to build a ship that bombs could not sink. Events proved both sides right and both wrong. Aircraft sank many naval vessels, but usually suffered appreciable losses themselves in the process. The Pacific war showed that warships of all sizes, shapes, and defensive strength were vulnerable to bombing, if the planes were present in sufficient numbers and if the flyers were willing to drive home their attacks regardless of cost. The same war showed that sea power—that is, the combination of naval force, applied by surface, sub-surface, and aircraft, and by merchant shipping—was a deciding factor in any struggle not conducted solely on land between nations whose territory is contiguous.
There were instances in which heavy bombing attacks on warships were beaten off without damage to the ships but with heavy casualties to the planes. There were instances in which the reverse was true. With atomic bombs, the accuracy previously demanded of the bombardier is no longer essential. He can drop his bombs from high altitudes, beyond the range of anti-aircraft fire; and no matter how fast is the target ship, or how quick its maneuvering, the bombardier knows it will not be able to escape the blast of his missile. There is, however, another side to this picture. Atomic explosives do not necessarily have to be dropped. They can be propelled. And they can be propelled by rockets far beyond the ability of antiaircraft guns to shoot or planes to fly. When they explode at such altitudes the effect on the rocket launcher which fires them will be nil, but the effect on any bomber within a mile of the blast will be annihilating. Mass aircraft raids are as doomed by atomic explosive as cities are by atomic bombs.
Rocket launchers can be built into ships. It has already been done. While the vessels presently so armed are mostly landing craft equipped with many small rocket launchers for close support of amphibious operations, there is no reason why large vessels, even cruisers or battleships, cannot be armed with bigger rocket launchers capable of using the famous German V-1 and V-2 or even heavier missiles. Armed with such weapons fitted with atomic warheads, and with antiaircraft rockets guided by radar or radio and themselves carrying a charge of atomic explosive, the warship of the future will be much more formidable than that of the past. It will be better able to defend itself and its merchantmen against attack from the sea or from the air. It is not too much to say, indeed, that the discovery of atomic fission and its control has given navies a weapon even more potent than it has given aircraft. One wonders whether it is not perhaps the air forces who should take thought for the future rather than the sea forces.
The sea-air controversy is not in reality a matter of great consequence. It was settled quite effectively by World War II. In a well- balanced military establishment both are essential. The discovery of atomic fission poses new problems which will have to be met satisfactorily by any nation which hopes to survive another war. The problem is one which concerns all the nation’s forces of defense, and it is a problem which this discussion makes no attempt to solve. It is essential, however, that in attempting to find a solution, sight is not lost of the effect of sea power on the war just ended, or of the continuing effect of sea power on any future struggle until such time as the control of atomic energy does away with shipping and permits the transportation over water of divisions of troops, heavy munitions of war, large quantities of materials by some means other than ships which sail the surface of the sea. Once the oceans have been eliminated as the world’s highways, sea power will cease to exist. Until that time, neither torpedoes, nor mines, nor submarines, nor aircraft, nor glide bombs, nor atomic bombs will affect the theory of sea power in the least except insofar as they act as weapons to make sea power even more effective than it was in the days of Admiral Lord Nelson.
A student at the University of Virginia and Johns Hopkins University before beginning a newspaper career, Mister Cranwell was on duty with the Military Intelligence Unit of the War Department during the war. He is a member of the U. S. Naval Institute, the U. S. Military Institute, the Maryland Historical Society, and the Peabody Museum Marine Associates. Besides contributions to the Proceedings and to other magazines and newspapers, he has published several books on naval and maritime subjects.