Navy

Germany’s decision to challenge Britain’s control of the sea was one of the major causes of World War I. Several naval battles were fought, and submarines were used extensively by the Germans to attack British trade. In World War II, the aircraft carrier, along with carrier-borne aircraft, and other military aircraft became the dominant weapons of sea warfare. Battles were fought without the opposing fleets coming in sight of each other, as bombers and torpedo planes inflicted heavy losses on surface ships.

As in World War I, German submarines (U-boats) were a threat to the Allied trade lifeline across the Atlantic, but aircraft proved effective in combating them. In the Pacific, the United States Navy’s submarines took a heavy toll on Japanese shipping, cutting Japan off from the source of raw materials. Radar and other advancements in electronic surveillance and communications, also introduced during the war, have since advanced the effectiveness of naval vessels.

During World War II, the US Navy replaced the British Navy as the world’s strongest fleet. Until the 1960s the Soviet Union had relied on its vast army for defence. After the end of World War II, naval warfare underwent a technological revolution as sweeping as that of the 19th century. Nuclear propulsion, introduced in the first nuclear submarine in 1954, greatly enhances the speed and endurance of warships and submarines, which no longer have to surface to recharge their electric batteries. Guided missiles replaced guns as the warship’s primary weapon, and the nuclear-powered strategic submarine (SSBN), fitted with nuclear-tipped intercontinental ballistic missiles that can be fired from beneath the sea, became a major component of the nuclear deterrent of the United States, Britain, and France.

In 1996 the US Navy had 8 SSBNs armed with 24 Trident C-4 missiles of range 7,400 km (4,600 mi), and 10 with 24 Trident D-5s, of range 12,000 km (7,452 mi). Britain’s first Trident SSBN, HMS Vanguard, armed with 16 Trident D-5 missiles, put to sea in December 1994; the second, HMS Victorious, entered Royal Navy service in December 1995. The third, HMS Vigilant, after its launch in October 1995, entered service in 1998; the fourth and final submarine, Vengeance, entered service in 2001. Each submarine carries 16 Trident D-5 missiles. While the submarines and (an estimated 240) warheads for British Trident are designed and made in Britain, the missiles are purchased from the United States.

France had 5 SSBNs with a total missile complement of 80. France, like Britain, has just finished modernizing its sea-based nuclear deterrent, and as of 2001 had 4 SSBNs. Its lead SSBN, Le Triomphant, was launched in 1993.

Accurate cruise missiles and torpedoes of increasingly long range and deadly potential have made large ships highly vulnerable. Modern navies can be increasingly expected to deploy their strike power under water, with the surface fleet concentrated on small but powerful and highly versatile vessels.