The role of destroyers changed because of their increasing design capabilities in the years before World War I and from wartime experience. Destroyers became superior in all respects to the torpedo boats they were designed to destroy. As a result, naval powers in the prewar years largely discontinued the production of torpedo boats in favor of destroyers. The destroyer assumed the offensive role of torpedo boat while retaining the role of defending against torpedo attacks launched by enemy destroyers. World War I added extensively to the duties of these vessels. By the end of that conflict, destroyers had acted not only in the roles envisioned for their type, but also as surface combatants and bombardment ships in amphibious operations. More important than these uses, however, was their use by Great Britain, France, and later the United States as escorts for merchant convoys to defend against submarine attack. Destroyers were particularly effective in this capacity after the wartime introduction of depth charges and underwater listening devices such as hydrophones and sonar.
World War I demonstrated the importance of destroyers, and the same basic types continued during the interwar years. Great Britain had such large numbers of the craft that fresh designs were not initiated immediately after the close of the war in 1918. However, destroyer construction in Italy led France to respond, as French politicians and naval officials viewed Italy as France's principal naval competitor in the Mediterranean. In 1923, France built large vessels that began a trend toward "superdestroyers" in the world's navies. Great Britain and Japan returned to destroyer production in the late 1920s; the United States did not initiate new construction until the early part of the next decade. Germany, although restricted by the Treaty of Versailles after World War I, began building new vessels at the same time as the United States.
This destroyer construction took place in an era of naval disarmament as the world's great powers sought to limit production as a means to prevent future wars. Unlike most other warships, few restrictions were put on the design and number of destroyers during the naval disarmament talks of the period. The 1930 London Conference limited destroyers to a maximum displacement of 1,850 tons and their guns to 5 inches or smaller, but these stipulations meant little. Until the late 1930s, the largest and most heavily armed designs met these requirements, and the limit was increasingly ignored after 1934 when the Japanese withdrew from the Washington Treaty and declared that they would not support future arms limitations discussions.
The American Somers-class is an example of destroyer design in the years immediately before the outbreak of World War II. Completed in 1937, the Somers measured 381' x 36' 11" and displaced 2,047 tons. She had exceptionally heavy armament: 8 x 5-inch guns, 8 x 1.1-inch guns, 2 x .5-inch weapons, and 12 x 21-inch torpedo tubes. The Somers had no armor protection and could steam at a maximum speed of 37 knots. Destroyers belonging to other naval powers loosely approximated the size, displacement, and armament of this vessel. France remained the exception as it continued to design destroyers that sometimes dwarfed those of other nations. The Mogador, launched in 1937, measured 451' 1" x 41' 7", displaced 2,884 tons, and carried no armor protection. It was armed primarily with 8 x 5.5-inch guns and 10 x 21.7-inch torpedo tubes and was capable of 39 knots. Despite the increase in the size and armament of destroyers, they were in most respects technologically the same as their World War I predecessors, although in some destroyer classes the largest guns were mounted in gun houses rather than open mounts to provide protection for crews. A further difference from the past was the incorporation of antiaircraft guns to fend off air attack.
By 1940, as during World War I, destroyers were the most numerous warships in the world's navies. Great Britain operated 247 destroyers of varying types and ages. The United States counted 149, and Japan had 116. Italy operated 90 destroyers. The other naval powers of the world also possessed large fleets: France maintained 66; the Soviet Union had 62; and Germany, through a naval policy that had violated the Treaty of Versailles, possessed 37.
World War II proved the continued importance of the roles destroyers had performed in the previous world conflict and introduced a new vital duty. In the Atlantic Theater, the primary task of British and Canadian destroyers was as convoy escort to guard against attack of merchant vessels by German submarines. This effort proved so important that the destroyer formed the basis for one of the first diplomatic agreements between Great Britain and the United States during the war. The 1940 Destroyers-Bases Deal transferred 50 aging World War I–era American destroyers to Great Britain in return for basing rights in the Western Hemisphere. Throughout the war, destroyers fought and helped to win the Battle of the Atlantic. Despite heavy losses in merchant vessels, ultimate Allied success in this effort allowed Great Britain to continue in the war. In addition, it enabled the transport of American troops to the European and Mediterranean Theaters after 1941.
Destroyers were also used as surface combatants, support for amphibious operations, troop transports, and resupply ships. An example in the Atlantic Theater of the first three of these roles is Germany's April 1940 invasion of Norway. Destroyers not only bombarded areas earmarked for the landing of troops, but they also attempted to fend off attacks from opposing British warships, and they transported a portion of the German ground force. The same roles existed for destroyers in the Mediterranean, where Allied vessels bombarded enemy positions during Operation torch, the November 1942 Allied invasion of North Africa. British vessels also acted as resupply ships for both the Allied troops in North Africa and the garrison on Malta, the principal British outpost in the Mediterranean.
These same roles were prevalent in the Pacific Theater, involving largely the forces of the United States and Japan. The Japanese used the destroyers both as surface combatants and as resupply vessels. Destroyers armed with the Long Lance torpedo were a key element of Japanese tactical operations and proved their effectiveness, especially in early night actions. The best example of a resupply effort was the famous Tokyo Express, which resupplied Japanese troops during the 1942–1943 contest for Guadalcanal. Destroyers were well suited for this resupply role as they were fast enough to make the voyage to Guadalcanal and depart still under cover of darkness. Early U.S. deficiencies in night-fighting were overcome, and American destroyers soon matched their Japanese counterparts in surface combat. In the August 1943 Battle of Vella Gulf, American destroyers sank three Japanese destroyers with no losses. The Japanese also used destroyers to protect convoys that supplied the home islands with war materiél.
In addition, use of destroyers in an antiaircraft role was widespread in the Pacific Theater. Both the Japanese and the United States sought ways to effectively defend their most important capital ships, the aircraft carriers. Destroyers partly filled the need for antiaircraft defense. This critical duty was reflected in the significant increase in the antiaircraft gun batteries of both Japanese and American destroyers during the war. The 12 Japanese Akitsuki-class vessels, launched between 1941 and 1944, mounted only 4 x 25-mm guns in addition to their primary armament of 8 x 3.9-inch guns, which could be used against surface targets or elevated and used against aircraft. By the end of the war, the complement of 25 mm guns had risen to 40–51 each for the surviving ships of the class. American destroyers showed the same shift to greater antiaircraft armament over the course of the war based on combat experience. By 1944, the 58 vessels of the Allen M. Sumner–class mounted a primary armament of 6 x 5-inch guns that could be used for surface combat or against aircraft and a smaller battery of 12 x 40-mm guns specifically devoted to antiaircraft defense.
The large number of critical roles performed by the destroyers and their consequent frequent use led to wartime construction that yielded an additional 633 destroyers among the principal naval combatants. The vast majority of these vessels were produced in the United States and Great Britain, which completed 392 and 165 ships, respectively. An example of wartime construction is the 150-ship U.S. Navy Fletcher-class. Launched between 1942 and 1944, these vessels measured 376' 5" x 39' 7", displaced 2,325 tons, and were protected by light side and deck armor. They were armed with 5 x 5-inch guns, 4 x 1.1-inch weapons, 4 x 20-mm guns for antiaircraft defense, and 10 x 21-inch torpedo tubes. They could make 38 knots.
The necessity for vessels to fulfill convoy escort roles also led to the production of a new type of destroyer that was cheaper and faster to build. Known as the destroyer escort, this ship was an essentially smaller, less capable destroyer with greater antisubmarine warfare capability. An example is the American TE-class escort, which measured 306' x 37' and displaced 1,432 tons. These were armed with 3 x 3-inch guns and an assortment of antisubmarine weaponry.
During the war, the belligerent powers constructed 915 destroyer escorts. The United States and Great Britain accounted for the majority of this production with 499 and 349 ships, respectively. The design of both the destroyers and destroyer escorts of the Allies and Germany and Italy benefited from the incorporation of radar, which was retrofitted to vessels produced before the war.
World War II exacted a heavy toll in terms of destroyers lost. By the end of the conflict, the belligerents had suffered a combined loss of 490 destroyers of varying types: among these, Japan lost 147; Great Britain suffered 133 sunk, largely in the Battle of the Atlantic; Italy lost 69 vessels; the United States counted 68 destroyers sunk; the Soviet Union lost 26; and France lost 14. Eric W. Osborne
Chesneau, Roger, ed. Conway's All the World's Fighting Ships, 1922–1946. London: Conway Maritime Press, 1980.; George, James L. History of Warships: From Ancient Times to the Twenty-First Century. Annapolis, MD: Naval Institute Press, 1998.; Preston, Anthony. Destroyers. Englewood Cliffs, NJ: Prentice-Hall, 1977.
Eric W. Osborne