Naval technology and tactics during World War II evolved around two areas that none of the navies thought to be critical before the War--carriers and submarines. Naval commanders in a tradition firmly implanted by Nelson at Trafalgur were wed to the idea of a major decisive fleet action. The Germans in World War I called it Der Tag--the Day. The German Navy was no longer capable of a major fleet action when World War II broke out. They had plans to build a massive fleet, but Hitler launched the War before that fleet was built. They had no choice but turn to a commerce war and use U-boats again. The British before the War did not think the German U-boats were a threat. The ASDIC (Sonar) developed in World War I had helped defeat the U-boat threat and British Admiralty was convinced that it made the submarine obsolete. This proved not to be the case. And once the War began, Hitler gave a priority to U-boat construction and the Germans made substantial technical advances. The Allies managed, however, to make even greater advances in anti-submarine warfare (ASW). The Americans and Japanese in the Pacific had both planned war winning fleet action, all based primarily on their big-gun battleships. Both countries developed fleet air arms, but it was widely believed that the expected fleet action would be decided by battleships. The Japanese termed the expected acton Kantai Kessen--Decsive Battle. The American plan to respond to a Japanese attack on the Philippine Islands was War Plan Orange. The Japanese plan Yogeki Sakusen was to use cruiser and submarine screns to weaken the American fleet and then finish it off with their battleships. The core of the Japanese battleship force was the massive Musashi and Yamato. Each had 18 inch guns which could outrange the 16 inch guns of the American battleships. The importannce of carriers was not understood before the outbreak of the Pacific War. One innovation that reached the Pacific Fleet just as the War began was Radar. The Japanese failure to develop effective radar technology serious impaired their naval operations. Unlike the Americans, they did not use their sizeable sumarine force in a commerce war.
World War II naval campaigns Figure 1.--The Japanese carrier attack on Pearl Harbor brought America into World War II. America was, however, unprepared for the War. Neither the Army or the Air Force had the capability of engaging the Axis with substantial force. America's first year of war was largely carried by the Navy, despite the battering at Pearl Harbor. The Navy with still limited resources engaged the German U-boats in the North Atlantic and the Imperial Navy in the South Pacific. And this is what the American public read about during the first year of the War. The U.S. Navy was the only Allied military force to achieve victory over superior Axis forces. The U.S. Pacific Fleet was unable to relieve the Americans on Batan and Corregidor. The Japanese swept through the South Pacific was only relieved by U.S. Navy carriers which carried Jimmy Dolittle's bombers to within range of Tokyo (April 1942). American carriers turned a Japanese invasion fleet back in the Coral Sea (May 1942). The first major American success was the decisive naval victory at Midway (June 1942). The first American offensive was the Navy's Marine Corps seizure of Guadacanal (August 1942). All this was accomplished in the face of superior Japanese forces. The outgunned, overstreached U.S. Navy managed to buy America a year to mobilize its considerable resources for global war. The Navy successfully carried out the Torch landings (November 1942). Only then did the Army and Air Force begin to engage Axis forces. Here these Boys Scouts in Baltimore are showing their support for the Navy.
World War II began in Europe with the NAZI and Soviuet invasion of Poland (September 1939). German U-boats immediatedly opened the Battle of the Atlantic, arguably the most important campaign of the War. Neither the British Royal Navy or the German Kreigsmarine were prepared for the War. Neither had expected the U-boat to bevso effective, but the Germans quickly realized they possessed a formidable weapon and expanded production of improied types. The fall of France provided Atlantic bases that made the U-boats even more deadly. For Britain, defeating the the U-boats was more than a matter if winning the War, it was a matter of national survival. And the U.S. Navy would join the Royal Navy in the North Atlantic even before America entered the War. Failure here woukld have cut iff Britain from America and the Dominions. The Japanese carrier attack opened the Pacific War. It would be the most titanic naval war in history fought out in the virtually limitless expanse of ocean. And the carrier would revolutionize naval warfare. The magnificent Japanse First Air Fleet was decimasted at Midway obly 6 months after Pealr Harbor. The Americans and British decided at the onset to give primority to the fight asgainst Germany. Even so, shipos and supplies from America arrived at a level that the Japanese could not match. The Allies launched two Paciic campasi\ns. One by the Army in the South Pcific and the other by the Navy in the Central Pacific. The conquest of the Matinas (June 1944) brought the Japanese Home Islands in the range of American bombers. A few months late the U.S. Navy in the Battle of Leyte Gulf (October 1944) fought the largest battle in the history of naval warfare, virtully destroying what was left of the Imperial Navy.
The two largest navies at the time of World War II were the Britis Royal Navy and the United States Navy. Both were much reduced from the much larger fleets deployed during World War I as a result of naval limitation agreements. These limitations were hated by the Japanese, but in fact allowed the Japanese to build a navy that could compete with the Americans and British. Only these countries deployed carrier forces of any importance which to the surprise of most naval commanders proved to be most powerful ship type. The Japanese built many excellent ships and manned them with well trainrd crews. They did not, however, have radar which proved to be a substantial weakness. And while their carriers had marvelously trained air crews, relatively little attention was given to fire suppression equipment and training. . With the onset of the War, the British withdrew most of their fleet to European waters. The American fleet was, however, divided between the Atlantic and Pacific. The Americans and British agreed on a Europe first strategy because Hitler and NAZI Germany were accurately assessed as the greatest threat. The U.S. Navy was committed to the North Atantic several months before America officially entered the War. The greatest sea battles were fought in the Pacific between the American Pacific Fleet and the Imperial Japanese Navy. The climax was the Battlevof Leyte Gulf when thevJapanese finally committed their two monsterous battleships. The most important naval campaign of the War was that fought in the North Atlantic. The Germans built excellent surface ships, but did not have a large enough fleet to take on the Royal Navy. As a result, the most important German naval effort was the U-boat campaign in the North Atlantic. The Germans did not, however, have gime beforecthe War go build a large U-bost fleet. Despite the focus given to German U-boats by World War II historians, the only successful submarine campaign in history was conducted by the U.S. Navy in the Pacific. France also had a substantial fleet, but played only a minor role in the War as a result of the German invasion. The Italians had an impressive fleet of fast, but lightly armored cruisers, but the lack of both radar and carriers meant that much of tt was destroyed by the Royal Navy in hard fought Mediterranean battles. Canada entered the War with Britain, but virtually without a navy, but during the War built a sizeable fleet, primarily to escort convoys.
At the onset of World War II, navies were ranked in terms of capital ships, meaning battleships. Naval technology and tactics during World War II, however, evolved around two areas that none of the navies thought to be critical before the War--carriers and submarines. Battleships became a ship type of only secondary importance, essebntially floating gun platforms to protect the carriers. And an entirely new class of ship rapidly developed--the landing ship. The Americans and Japanese in the Pacific had both planned war winning fleet action, all based primarily on their big-gun battleships. Both countries developed fleet air arms, but it was widely believed that the expected fleet action would be decided by battleships. The core of the Japanese battleship force was the massive Musashi and Yamato. Each had 18 inch guns which could outrange the 16 inch guns of the American battleships. The importannce of carriers was not understood before the outbreak of the Pacific War. While the carriers made the headlines, each of the different vessel types played important roles. Destroyers were multi-purpose vessels, including pritection for the fast carriers. Cruisers provided big-gun support in situations when battleships were not available. The battleships were the floating gun platforms to pulverize beach defenses and for anti-airctaft fire to break up Kamakazee attacks. Submarines played an important role in the war. Most accounts focus on the U-boats who ultimtely failed. Unlike the Americans, the Japanese did not use their sizeable sumarine force in a commerce war.
World War II has been called a 'war of logistics'. In this sence the German's failed even though they had the easiest logistical challenge. They were located in the heart if Europe snd gfoighting a continental war. The country's which faced the bigest challenge were Japan and America and to a lesser extent Britain. For the Soviet and Germans the lgistical system was diominated by the railrod. For the Americans and Japanese logistics primarily involved shipping. This meant shipping in the Pacific for the Japanese. For the Americans it meant a world-wide shipping challenge, but primrily the Pacific and North Atlantic. The British faced the same challenge, but as their war was primarily fought in Europe and the North Atlantic, it was not the same global challenge America faced. Shipping thus was a major
aspect of the War. In no other War in history has the shipping challenge been so immense. The enormity of the challenge was part of the German strategic calculation. They didn't believe that it was a challenge even America's vaunted industrial genius could master, at least within a time frame that would prevent them from mastering Europe. For the Japanese, preoccupied with naval construction, they simply failed to calculate the shipping requirements for a Pacific war. The role of American industry, the Arsenal of Democracy, is commonly addressed in World War II histories. The War was, however, not fought in America. And all those tanks, trucks, artillery, machine guns, ammunition, electronic equipment, oil, food, and other supplies was of no use unless it could be delived to the front lines. And this primarily meant shipping--shipping on a vast scale. Merchant mariners from German occupied countries joined the British war effort, but the game changer was the Henry Kaiser and his war-winning Liberty Ships. The Germans assumed that the Americans needed 9 months to build a ship. That was how long they took to build a merchant ship and they considered themselves highly efficient. When reports surfaced of the Americans building merchant ships in 10 days, the incedulous Germans dismissed the reports as absurd propaganda. But they were all too true. Even before the Allies defeated Adm. Dönitz's U-boat wolf packs (July 1943), the United States was building merchant ships much faster than the Germans could sink them. And American shipyards also produced needed merchant shipping in large quantiyties for the Pacific. While the U-boats get a huge smount of attention by historians and Hollywood. It is the U.S. Pacific Fleet Submarine Service that waged the only successful commerce campaign of the War--obliterating the Japanese Maru fleet. This cut the Home Islands off from their recently conquered Southern Resource Zone--the reason the Japanese went to war in the first place.
For the first time in naval warfare, aircraft played an important role. A major aspect of the War was that the carrier replaced the battleships as the key capital ship. And the carrier was nothing more than a floating airfield capable of moving aircraft in range of enemy fleet formations and land targets. Only three countries (America, Britain, and Japan) built and deployed carriers. The Germans had plans to do so, but military reverses precented them from doing so. The Japanese began the War with the most effective carrier aircraft, especially the elegant, but lightly armored A6M Mitsubishi Zero (1941). The Japanese did not design aircraft specifically for carrier use, but rather adapted aircraft for multiple uses. The Japanese because of their limited industrial capacity did not introduce new advance aircraft types. Their pilots were still using the Zero when the climatic naval battles were fought (1944). Britain began the War still using the venerable Fairey Swordfish biplane. It was the United States which created a remarkable series of aircraft specifically designed for carriers. These planes combined with new fast carriers suceeded within only 3 years swept the Japanese from the skies over the Pacific. The Pacific Fleet began the War with the rugged, but slow F4F Wildcat fighter. It was vulnerable to the faster Zero, but tactics were developed which reduced the Japanese advantage. It was the F6F Hellcat that transformed the Pacific War. American aviators in Hellcats destoyed over 5,000 Japanese planes. The Douglas SBD Dauntless dive bombers ravaged the Japanese carriers at Midway. The Grumman TBF Avenger torpedo bomber played a major role in the crucial Battle of the Philippine Sea. [Sears] The fork-winged Chance Vought F4U-4 Corsair was another powerful fighter, but took time to develop carrier usage.
The Japanese began the War withe best-trained and most competent pilots of Wirkd War II. Their principal weakness was the small number. Not only did the Japanese lose carriers at the Coral Sea and Miday, but the core of their carrier pilots was desimated and further attrited in South Pacific campaign. The Japanese had a superb pilot training program, but it was highly selective and long. It was designed to produce small numbers of suberb pilots. As the short, quick war turned into an extended war of attrition, the Japanese did not modify their training program. They were thus unable to turn out competent carrier pilot to replace the extensive losses in 1942. The Japanese training program was also hamperd by oil shortages. America in contrast launched an extensive pilot training program which crewed the new cartriers flowing out of shipyards in incredible numbers. The American pilots were not as well trained as the initial Japanese pilots, but they were competntly trained and soon gained battle expoerience. In addition a new generation of Americn planes reached the fleet which were superior to the lightly armoured Zero.
The principal naval platfprm was the same as had always been the case--ships. We deal with ships above. World War II added a second important platform for projecting naval powe--airplane. We also addrrss this topic above. The fighting ships of the various navies are essentially gun plaforms for various types of naval artillery. Both were platforms for weaponry. Before World War I, naval planners had decided that what ws important were the large naval guns, resulting in HMS Dreadnoughts and the battle ships of World War I. After the War, however. naval designers saw the need for large mumbers of small guns as a result of the need for anti-aitcraft armament. This need was amplified by combat experience during the war. Another World War I innovation was the torpedo which became a major weapon system, giving small ships without big guns the ability to sink capital ships. They were carried by both surface ships and submarimnes as well as aircraft. Inadittion ti guns, naval shops also carried anti-sunmarine warfare (ASW) weapons. The most iomportant was the depth charge used in World War I. They were suplemented durung the War by the hedgehog. Another important naval weaoon system is mines. Naval mines played an important role in World War II although not as important as World war I. The German seizure of Norway and subsequentky France meant that the British could not create an effective North Sea mine barrier to restrict U-boat opeations as rhey did in World War I. Both the Germans and British used mines in the Battle of the Atlantic. The Germans devised some novel minds, but they were quickly countered by the British. The Americans used mine to tighten the blockade around the Home Island at the end of the War. Ordinance, the shells fired by naval guns was similar in many way to Workd War I. An important development which greatly assisted the U.S. Navy was improvements in anti-aircraft guns as well as shells with proximity fuses. The rapid firihg Bofar guns significantly improved ship anti-airrcraft capabilities. One major advance by the Allie was the proximity fuse. It was at first only used in the Pacific in naval actions to make sure the shell and secret of the fusing could not fall into German hands. Electronics played a major role in the War. Sonar and Radar were the most important of these devices. Sonar or ASDIC was invented by the British during Wotld War I and became a key element in anti-submarine warfare (ASW) operations The British were surprised to find that their SONAR was not very effective against the new advanced German U-boats. Another electronic device that reached the Pacific Fleet just as the War began was Radar. The British developed RADAR to defeand against air ttack. It was soon realized that it had naval aplications. Radar could be used to defend agaunst air attack as originally intended or in ship to ship applications. Radar could locate enemy ships as well as to direct naval gunfire. The cavitron permitited the minurization of radar sets so they coukd be put on all ships as well as eventually even on aircraft. And American had the manufacturing ability gto produce them in massive numbers. The Japanese failure to develop effective radar technology or to acquire German radar seriously impaired their naval operations.
Naval commanders in a tradition firmly implanted by Nelson at Trafalgur were wed to the idea of a major decisive fleet action. The Germans in World War I called it Der Tag--the Day. The German Navy was no longer capable of a major fleet action when World war II broke out. They had plans to build a massive fleet, but Hitler launched the War before that fleet was built. They had no choice but turn to a commerce war and use U-boats again. The British before the War did not think the German U-boats were a threat. The ASDIC (Sonar) developed in World War I had helped defeat the U-boat threat and British Admiralty was convinced that it made the submarine obsolete. This proved not to be the case. And once the War began, Hitler gave a priority to U-boat construction and the Germans made substantial technical advances. The Allies managed, however, to make even greater advances in anti-submarine warfare (ASW). The Japanese termed the expected acton Kantai Kessen--Decsive Battle. The American plan to respond to a Japanese attack on the Philippine Islands was War Plan Orange. The Japanese plan Yogeki Sakusen was to use cruiser and submarine screns to weaken the American fleet and then finish it off with their battleships.
Inteligence ws especially important in naval warfare and here code breaking was especially important. This was because oceans cover vast areas. Vast amounts of naval power can be expended in just locatig the enenmy. The side that could locate the enenmy and learn of his intentions had an enormous advantage. This was especially true of carrier warfare. The carrier was a very vulnerable target, esentially a floating combination amunituiionn dump and fuel depot. As a result, the country which located the enemy carriers and launched first was likely to deliver a crippling blow.
Sears, David. Pacific Air: How fearless Flyboys, Peeerless Aircraft, and Fast Flattops Conquered the Skies in the War with Japan.
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