Naval strategy and tactics have been shaped by the forms and capabilities of naval warships (see navy). Geography is also an important factor in shaping naval thinking. In the Mediterranean, and for islands such as Britain, strong navies were crucial. For the many empires of the Middle East, the Central Asian steppes, or India, naval power was less important or superfluous. Not until Alfred T. Mahan wrote The Influence of Sea Power upon History in the last decade of the 19th cent. was the central theme of naval strategy formulated in universal terms, although the British had been practicing it for hundreds of years. The main strategy of sea power was defined as "command of the sea," i.e., the ability to deny use of the sea as a means of transportation to an enemy while simultaneously protecting one's own merchant shipping, and the ability to use the sea to project power ashore while denying that capability to the enemy. Despite the introduction of new weapons such as steam warships, armored ships, heavy ordnance, submarines, and aircraft, "command of the sea" remained a fundamental objective of naval strategy. Another important naval strategy is "overseas presence," i.e., the visible display of seapower as a deterrent to intervention by opposing powers in key areas of international tension.
The development of airpower has led to a host of changes, including the emergence of aircraft carriers and naval air fleets and the development of submarine-based retaliatory missile forces. The employment of land-based and carrier-based aircraft during World War II showed that command of the seas rested in great part on control of the air above it. The submarine, introduced in World War I, greatly changed naval strategy and led to the development of many new weapons and tactics. In both world wars the submarine was employed mainly as a commerce destroyer and, as such, could not by itself gain command of the sea. However, the use of long-range guided missiles on nuclear-powered submarines in the 1960s transformed the submarine into a major weapon of strategic bombardment. Nuclear-powered submarines carrying guided missiles are almost invulnerable to attack.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.