ABSTRACT
The basis of all naval strategy is a simple physical fact: it is far easier to move anything by sea than over land. That is why the great bulk of the world’s trade goes by sea, why an air base or a missile field can travel by sea (in the form of an aircraft carrier or a missile submarine), and why so much of the world’s population lives either near the sea or near a major river. This is also why ships can lie off a coast for a protracted period, whereas ground troops have to be ashore, and aircraft offer only intermittent presence. Another fact is the sheer vastness of the sea. It is still difficult to maintain any sort of wide-ocean surveillance. Particularly in wartime, anyone threatened with attack from the sea must deal with a wide variety of possibilities, not knowing where the attack may fall until just before it does. It is impossible to defend against everything. The defender either disperses his forces (offering the sea-based attacker potential local superiority) or leaves major areas undefended. This possibility has been exploited in numerous amphibious operations. In a larger sense, it gives a sea-based force remarkable leverage for its size. However, it takes a considerable investment to exploit sea-based mobility.
Navies therefore always have had limited numbers, and physically they cover only a tiny fraction of the sea at any one time. Alternatively, it might be said that navies have always had to use technology to leverage limited manpower. All military services are now in this position, but for centuries seapower meant the power of technology and industry, whereas land power meant numbers of men, inexpensively equipped. With enough men, it was possible to cover large land areas; but there can never be enough navy to cover even a small sea area. Sea control means something very different from land control. That the sea remains dominant is less obvious in an age of fast mass air travel,
but anything heavy still goes primarily by sea. For example, in both Iraq wars, something like 90%–95% of the mate´riel used by the coalition forces arrived by sea. The great issue is how to use the sea while denying its advantages to an enemy. Because the sea is trackless, denial cannot be absolute, but it can still be well worthwhile. In the SecondWorld War, the Allies largely denied the sea to the Germans. The Germans could still mount a devastating U-boat offensive against the Allies, but they could not cross a narrow sea to invade Britain, and later they found it rather difficult to supply Rommel across the narrow Mediterrranean. Because the sea itself confers mobility, it is trackless. Geography has far less power over what happens off shore, the important exceptions being choke points formed by land. Thus merely finding hostile forces in the open ocean is difficult at best. It has become an important theme in naval warfare. To some extent merchant shipping follows established routes, but only because they offer better
fuel economy. In wartime, evasive routing has been an important means of protecting merchant ships from attackers. A second and increasingly important factor in naval or maritime strategy is that
the sea contains important resources. In the past the main sea resource was fish, but now there are also valuable mineral resources, particularly oil. Unlike resources on land, those in the sea cannot readily be defended by surrounding them and blocking access; access is over so wide an area that it must always be fairly free. With the advent of the United Nations treaties on the Law of the Sea, countries have 200 nautical mile-deep Exclusive Economic Zones (EEZs) off shore, but it is an open question whether they can be controlled or defended. Even a 200-nautical mile swath off a coast is virtually impossible to control by patrols or by continuous surveillance, and that difficulty is small compared to the problems of the open ocean, or of defending against missile attack from the sea.
