It was the Japanese carrier attack on Pearl Harbor that brought America into World War II. Had the Japanese not attacked, it is unclear just when America would have entered the War. The Japanese Imperial Fleet was a superbly trained force with modern, well designed vessels. Many naval experts at the time did not fully appreciate the effectivness of the Imperial Navy. The lack of radar, however, proved a huge disadvantage. Allied radar and many other technical advances were the result of close cooperation between American and British scientists anf joint development projects that began even before America entered the War. There was no comparable Axis technical cooperation or even coordination of military campaigns. The Kriegsmarine had very effective radar on its surface ships like Bismarck yet advanced German technology like radar, jet engines, and other equipment was not provided to the Japanese until very late in the War, too late to be of any effective use to the Japanese war effort. While Pearl Harbor was a stunning tactical victory, it was a strategic blunder by the Japanese of incaluable proportions. The Japanese were able to seize much of Southeast Asia, but the stunning American carrier victory at Midway, significantly reduced the strike capability of the Imperial Navy. This provided the time for American industrial capacity to reated a naval force with which Japan's limited industrial capacity could not cope. While the German submarine campaign in the North Atlantic failed, the American submarine campaign in thePacific proved spectacularly successful. The Japanese merchant marine was almost completely destroying, cutting the country's war industries off from supplies and bringing the country close to starvation. Amercan industrial strength enabled America to build a naval force capable of leap froging from island to island. The Navy by 1944 had seized islands from which the Japanese Home Island could be bombed. The Navy also enabled the Army to retake tNe Guinea and the Phillipines and by 1945 Okinawa. Naval and Army forced were preparing for a full-scale amphibious invasion of the Home Islands when two atomic bombs were dropped (August 1945) and Japan finally surrendered (September 1945).
China for several centurues after the first European ships arrived restricted foreign trders desiring to do business in China. One major concern was that the Europeans had little the Chinese wanted. This ended with the British Opium Wars (mid-19th century), forcing the Chinese to permit imports of opium. The British and other Europeans forced the Chinese to open their ports. The Europeans also forced territorial concessions and extra territoriality. The Chinese who had for centuries been the dominant power in Asia, suddenly found that their armies and navy were impotent against European forces with modern weapons. The Chinese lost the Sino-Japanese War (1894-95) with the rapidly modernizing Japanese. The Boxer Rebellion was a reflection of Chinese frustration (1900), but only depened the decline of Chinese power. The Europeans controlled Hong Kong, Wei Hai Wei, and Tsingtau, or had concessions in ports like Canton and Shanghai. The United States promoted the Open Door Policy, but was concerned with its interests. The European powers to protect their commercial interests and citizens in China maintained naval forces in various places in the Far East, including China. This became known as China Station. The United States had an interest in trade as well as after the Spanish American War (1898-9) possession of the Philippines also maintained a squadron in China. Of particular concern was Shanghai, China's principal port, located at the mouth of the Yangtze River which led into the inteior. To ensure that the river was kept open, a new clas of vessel with shallow drafts were developed--China gunboats. The purpose was to 'show the flag', fight pirates, and protect foreign-owned vessels plying the river. Small ships like destroyers and mindsweepers could also enter the lower Yangtze up to Nanking. The China Station proved to be colorful duty, but there were dangers. The Yangtze is one of the world's geat rivers. It is also wild and unpredictable in many areas. Small craft like gunboats could be driven ashore or smashed on the rocks in the towering gorges. Pirates were a continuing problem in the unsettled conditions of the early-20th century. And this increased as the Imperial regime came apart. Then there was for several years the problem of war lords. There were several incidents during the 190s when foreign ships were attacked. There were several such attacks during 1927. Japan invaded China (1937). Foreigners were caught between Chinese and Japanese forces, especially in the first year of the War which involved conventional operations and centered on Shanghai and the Yagstze river ports leading to Nanking.
The Americans and Europeans continued to maintain a presence in China as best they could. The Panay incident was a clear indication of Japanese intentions (1937). European warships called at Shanghai and were fired on or threatened by the Japanese. With the outbreak of World War Ii in Europe, the British and French graduallywithdrew removed their forces from China. Only leaving only a few small vessels to show the flag. As the European and American presence waned and the Japanese occupied most of coastal China, they became increasingly assertive, imposing control over movement of foreign warships in Chinese waters. The United States by late-1941 also largely withdrew.
The major powers after World War I chastened by the incredible loss of life and destruction persued a policy of naval disarmament. The Treaties flowing from the Washington Naval Conference (1921-22) limited national fleets. Interestingly, Admiral Yamamoto suggested that battleships be scsrapped. I am not sure what the Japanese onjective was with this proposal. It was not taken seriously by the other naval powers. One result was that the Japanese began to take an interest in carrier which were not covered by the treaties. A naval building program was persued in viloation of the treaties, although I am not sure when this begun. Certianly the construction of Mustashi? and Yamato far exceeded the limitations (1937). The Japanese Navy was disturbed that the Japanese did not receive parity with the American and British fleet. Many advocated an aggressive preparation foe war. Others such as Admiral Isoroku Yamamoto insisted that war with America and Britian would be suicidal because of their superioir industrial and technical capaboility. Yamaoto was for a time targeted for assasination. He was, however, appointed commander of the Imperial Navy. He was an inovative strategist and in particular propmoted the naval air wing.
The League of Nations assigned the South Pacific Island Mandate (Nan-Yo) to Japan. Japan fought with the Allies in World War I. The Mandate covered a large part of Micronesia and were former German colonies. The Mandate included the Carolines, Marianas, Marshall Islands and Palau archepeligoes. An exception was made for Guam which continued under U. S. administration. The South Pacific Mandate was put under the control of the Japanese Navy. The Governors appointed were mostly admirals or vice-admirals. The Mandate capital was Koror, in the Palau islands. The most important island was Saipan in the Marianasa for both military and economic reasons. Sapan also became a major center for Japanese settlement. Another important island militarily was Truk (now Chuuk), in the Carolines. The Imperial Navy referred to it as the Southern Gibraltar. Japan withdrew from the League (1935). This invalidated the Mandate, but Japanese had by this time integrated the islands into the Japanese Empire. Large numbers of Japanese immigrants had settled on the islands, especially Saipan. The Japanese Navy built airfields, fortifications, ports, and other military instaltions. Construction of military instalations was escalated after Japan withdrew from the League. These islands were to be major battlefields in the Pacific War.
The major naval powers (America, Britain, France, Italy, and Japan) agreed to substantial limitations on their naval strength which at the time was measured in battleships. American Secretary of State, Charles Evans Hughes organized a conference to address the problem of spiraling naval expendidutres as a result of the naval arms race. Senator William E. Borah, Republican of Idaho, who had led the fight against American ratification of the Treaty of Versailles and participation in the League of Nations, strongly advocated efforts to limit the arms race. His efforts were not at first favored by the new Harding administration, but was eventually adopted as the Republican alternative to the Democrat's (Wilson's) policy of collective security through the League of Nations. The Confrence opened on Armistice Day 1921--a very meaningful date so close to World War I. The American delegation was led by Secretary of State Charles Evans Hughes. Hughes shocked the other delegates by proposing a major reduction in naval fleets and not just limitations on new construction. This was far beyond what the other countries had anticipated. Some have called this one of the most dramatic moments in American diplomatic history. The American proposals entailed scrapping almost 2 million tons of warships as well as alengthy “holiday” on new building. The consequences of the Washington Treaties went far beyond this.
The world naval powers convened in London to discuss continued naval arms limitations. The London Conference was strongly promoted by British Prime Minister Ramsey MacDonald who desired to continue if not increase the limitations established by the Washington Naval Treaties (1921). The Conference was held as the Wall Street Crash (1929)was spiraling into a serious world-wide economic criis and the major powers desired to cut back on gobernment sopending, especially military power. A Treaty was signed (April 1930). The signatories agreed to build no replacements of capial ships before 1937. American, Britain, and Japan agreed to avoid a arms race in destoyers and submarines. They also for the first time placed limits ob cruisers. America and Britain were allocated a cruisr tonnage about one and half that of Japan. The partipants agreed to another naval arms conferemnce in 1935. The inferior status of Japan has caused considerable resentment after the Washington Naval Conference (1921-22). After the London Conference it set in motion political changes of serious consequences.
The Americans and the British attempted to convene another naval arms conference (1935). The major naval powers met in London for another round of naval talks to renew the existing limitations decided on at the Washington Naval Conference (1921-22) and London Naval Conference (1930). These limits were due to expire (1935-37). The militarsts in Japan were now in virtual control of the Government. The Japanese demanded parity with America and Britain. When this was not granted, the Japanese withdrew from the planned conference. This meant the exisiting limitations would expire. All three nations initiated battleship rebuilding programs with expiration of the treaty in 1936. Japan initiated the largest building program, a massive program to build 150 ships. The Japanese laid down two super battleships, Yamoto and Musashi, but the actual dimensions of these massive ships were kept secret. They were 69,100 tons, twice the size of treaty limitations. Germany built Bismarck and Tirpitz at 52,600 tons. The falure of the Conference created enough concen in Congress to approve an American naval building program, although a smaller program than initiated by the Japanese, only 100 vessels. Even so the new ships would only bring the Navy up Treaty limits. Two aircraft carriers were laid down in 1936 and 1937, each within Treaty limits. (These were USS Wasp (CV-7) and the larger USS Hornet (CV-8). No one knew at the time just how importnt these carriers would be. Both would reach the fleet in 1941 in time to participate in the critical Pavific battles of 1942. The Rooevelt Administration justified the appropriations in part as they would create jobs. The Isolationists and peace lobby opposed the appropriations with the slogan "Schools, not battleships". New battleships were authorized, but actual keels were not laid until after the war began in Europe. Only the USS North Carolina (BB-55) reached the fleet before Pearl Harbor.
Yamamoto and other naval officers appreciated the industrial potential of America. Japanese Army commanders had no such apprecition. In addition, the Japanese Army in 1939 fought an undeclared war with bthe Soviets along the Manchurian border. The Japanese Army had suffered substantial losses and were not anxious to persure another campaign against the Soviets. American support for China caused Army officers to advocate a war with America. Many in the Army had convinced themselves that fighting spirit could over come American industrial superiority. As the British were engafed in Europe and France and the Netherlands occupied, their colonies with key natural resources needed by resource-poor Japan seem easy prey. The only other creditable force in the Pacific was the American Pacific Fleet at Pearl Harbor. The Army in 1941 dominated the Japanese Government.
The U-boat successes in 1940-41 had a significant impact on the Pacific naval campaign. The Battle of the Atlantic was perhaps the most important single struggle in World War II. Defeat here would have forced Britain to capitulate and Aamerica could have not poarticipated in the European conflict. The power ballance in the Pacific was made even more lopsided by the fact that most of the Royal Navy had to be deployed in the Atlantic to keep the sealanes open. Until Bismarck was destroyed, the British battleships and carriers had to be concentrated in the North atlabtic. Even though America was legally neutral, by 1941 the Roosevlt Administration was not only supporting Britain, but engaging in an undeclared naval war in the North Atlantic.
The Japanese Imperial Navy (Nihon Kaigun) by 1941 was the dominant naval force in the Pacific. The Japanese had a large well-trained naby with excellent ships. There was no peace-time neglect as the British and U.S. navies experienced. The American Navy was aware that the Japanese had a modern effective navy, but did not fully understand the campabilities of the Imperal Navy or the danger posed by the sizeable carrier fleet. The Japanese Imperial fleet was superbly trained with outstanding night fighting capabilities. Not only was the fleet well trained and included modern vessels, many of the Japanese vessels and naval aircraft were supperior to American and British vessels in many aspects. Japan led the world in operational aircraft carriers and carrier aircraft. (The British in 1941 were still using Swordfish biplanes on their carriers and American planes, especially the fighters were slower and less manuerable. The Japanese Mitsubishi Type 00 fighter, the Zero, was both faster and more maneuverable than either the U.S. Navy carrier fighter, the Grumman F4F Wildcat. The full extent of the threat was in part obscured by American rascial sterotypes and wide-spread belief that the Imperial Navy was not an effective force. In reterospect, the only suprising question about the attack on Pear Harbor and Japanese offensive in the South Pscifiuc, is not how they succedded, but how America managed to stop the Japanese after only 6 months of victories. The two glaring weakeneses were the lack of radar and the ineffective fore supression systems. Not well understood is that Japan had a very substantial submarine fleet.
Looking back as a historian, it is almost incomprehensible that Japan decided to wage war against the United States. War with Britain and the Netherlands is more understandable. Britain in 1941 looked like if not a defeated nation, at least a severely weakened one. The Netherlands was occupied by Axis ally NAZI Germany. America is a very different matter. The United States was not at war. It had not been weakened by the War. And Japan had no commitment that the Germany would join them if they attacked America. War with America seems like an extrodinarily wreckless decession for a country already mired down in a war with China and that had experienced a sharp defeat in a short war with the Soviets. Why would Japan have decided on war with America, a country with a larger population and a much larger industrial and scientific base. The road to war began early in the history of modern Japan. Wars with China (1895), Russia (1904-05), and Germany (1914-18) proved both short and profitable, enabling Japan to build a small empire. The risring influence of the military brought to power men of limited outlook who saw military action as a legitimate use of sate power. They were backward looking men who saw the European empires of the 19th century as to what Japan should seek to establish. And they were men who were strongly influenced by the historic image of the Samurai and Bushido which convinced them that Japanese racial superiority and martial spirit could prevail over the material supperority of America. Despite the power of American induistry, tgey saw Americans as a weak, decadent people who would not fight. Most of the Japanese militarists who made this judgement on which the very life of Japan would hang, knew no Americans and had little or no experience with Ameica.
It was the Japanese carrier attack on Pearl Harbor that brought America into the War. While Pearl Harbor was a stunning tactical victory, it was a strategic blunder by the Japanese of incaluable proportions. It was a stunningly successful military success, brilliantly executed by the Japanese. Eight battle ships, the heart of the American Pacific fleet were sunk. But the three carriers were not at Pearl. Despite the success of the attack, it was perhaps the greatest strtegic blunder in the history of warfare. The Japanese attack on the Pacific fleet at Pearl Harbor changed everything. A diverse and quareling nation, strongly pacifistic was instantly changed into a single united people with a burning desire to wage war. The issolationism that President Roosevelt had struggled against for over 7 years instantly disappeared. Even Lindburg asked for a commision to fight for the United States.
Both the American and Japanese Navies had concluded before the War that if war was to come, it would be decided by a major fleet action at sea in which the deciding factor would be the big-gun battleships. The destruction of the American battleships at Pearl Harbor forced Admiral Nimitz when he took command of the Pacific Fleet to develop a new strategy. The only strategy open to Nimitz was to put the air craft carriers which had survived the Pear Harbor attack. The problem here was that the Japanese had a vastly sup[erior carrier force. Not only did the Japanese have many more carriers, but their pilots were more expeienced and better trained and the planes had superior performance characteristics. And the battle groups formed around the carriers after Pearl Harbor included cruisers to defend the carriers, vessels that were no match to the battleships of the Imperial Navy. The question was not wether the Navy could stop Japanese invasions of the Phillipines, Malaysia, and the Dutch West Indies, but wether the Pacific Fleet could even prevent its own destruction and defend the Hawaian Islands.
With the American fleet impobilized at Pear Harbor, the Japanese were able to sweep through the Pacific and Southeast Asia. Guam was quickly taken. Resistance at Eake sland suprised the Japanese, but after the initial assault was repulsed, a second assault took the island. MacArthur's defense of the Philippines was compromised when most of his planes were destroyed on the fround at Clarke Field. General MacArthur commanded the most important American military force west of Pearl. His handlong of the defense of the Philippines wasdisapponting at best, bordering on incompetence. He failed to strike back at the Japanese in the hours after the attack on Pearl Harbor by bombing Jpanese bases in Formosa. He also allowed much of the available aircraft to be destroyed on the ground. [Schom] The horror of the Batan Death March created an impage of the Japanese military in the American mind that fueled a hatred for the Japanese. [Schom] Hong Kong quickly fell. The Japanese also seized the oil-rich Dutch East Indies (modern Indonesia). Allied naval forces fought a series of engagements to stop the Japanese, but could not match the powerful Japanese naval forces. Animitz and Halsey tried to distract the Japanese with hit an run carrier raids. The Japanese moved south from IndoChina, seizing Malayia and then the bastion at Singapore. The Repulse and Prince of Wales are lost in the defense of Singapore. Then they moved west through Thailand and defeating the British in Burma. Within a few months the Japanese had carved out the huge empire with enormous resources that they had long coveted. The Japnese then targeted New Guinea in preparation for a move south to Australia. All that remained to stop them were four American carriers.
The Japanese strategic concept was to seize a huge empire and then fortify it so that it would be enormously costly for the Americans to retake. The resources from the empire which the Japanese called the Greater East Asia Co-Prosperity Sphere were to be used to support the Japanese military. The Japanese with little knowledge of America were convinved that America would never make the sacrifices needed to retake the Japanese conquests. This strategic concept was fataly flawed. First, the attack on Pearl Harbor turned a biterly divided America into a unified, mortal enemy. Second, the Japanese strategy had no provision for attacking the industrial base of the United States, an industrial base far exceeding the industrial capacity of Japan. Third, the Japanese were unprepared for the American submarine campaign, a campaign which by 1943 was beginning to deny Japanese industry the resources from their newly won empire. THe Japanese found their army bogged down in unwinnable campaigns in China and Burma and morooned on isolated Pacific islands that they could no longer supply.
The radar developed by British and American scientists proved a huge advantage to the american Navy in the Pacific campaign. The Imperial Navy had no radar. This was one of many examples of the Axis failure to share military technoology. The Germans developed higly effective radar systemns, both for air an naval warfare. The Bismarck sunk by the British in 1941 (months before Pearl Harbor) for example had an effective radar system. If the Germans had supplied this technology to the Japanese in 1939-40, the Pacific naval campaign would have beren much more difficult than it was. The Japanese would, for example, fared much better at Midway. After the War had turned agasinst the Germany, a technology excjange was arranged with Japan. I am not sure radar was involved, but by then it was too late for the Imperial Navy which after the Battle of Letye Gulf was no longer an effective force.
Allied radar and many other technical advances were the result of close cooperation between American and British scientists anf joint development projects that began even before America entered the War. There was no comparable Axis technical cooperation or even coordination of military campaigns. The Kriegsmarine had very effective radar on its surface ships like Bismarck yet advanced German technology like radar, jet engines, and other equipment was not provided to the Japanese until very late in the War, too late to be of any effectiveuse to the Japanese war effort.
The Japanese after Pearl Harbor launched a series of invasions designed to seize territory that wouuld supply the natural resources that the miltarists so coveted. Here they were enormously successful. What they failed to do was to launch a knock out blow against the American Pacific fleet. Although the american carriers had not been at Pearl, the Japanese had a 3:1 superority in carriers. The Japanese superority was not just in numbers, but they had better planes and more experienced flight crews. Japan to win the War had to use its naval superority in 1942 to destroy the Pacific Fleet. Given America's industrial might, the naval superority would be rapidly closed by 1943. Thus Japan should have forced the Pacific fleet to battle in which it could deploy its massive carrier force against the Pacific Fleet's much smaller force. Instead of striking at Pearl, the Japanese instead deployed carriers to the Indian Ocean and in operations preparing for an invasion of Australia. Each of these were marginal undertakings in a war against America and the key American force, the Pacific Fleet. Japan failed to do this. In fact, the Pacific Fleet managed to deploy its carriers so effectively that the two major fleet engagements during 1942 (Coral Sea and Midyay) were fought on relaively equal terms. It is a mistake of clossal proprtions when you have a 3:1 superority in carriers to flight fleet engagements on equal terms. The primary maxim of carrier warfare is the force which first spots and launces on enemy carriers is likeky to win the engagement. For this reason you never want to fight an engagement on equal terms. With a larger carier force, you can launch on the enemy carriers even if he finds some of your carriers force. The Japanese ignored these basic maxims and as a result, the Imperial Navy's carrier superority was squandered and America had the time it needed to build a fleet of unimaginable size and power.
The American Pacific fleet carriers by a fortuitous accident of history were not at Pearl wheen the Japanese struck (December 7), And it was the Pacific fleet carriers that were the primary Japanese targets. It is a massive Japanese failure. Admiral Halsey brought Enterprise into Pearl to the scene of a bloodied and still smoldering fleet (December 8). The ship was huredly resupplied and left Pearl to seek out the Japanese fleet (December 9). The Japanese carrier task force had long since departed. This was actually another fortuitous circumstance. If Enterprise or the other American carriers had encountered the six carriers of the Japanese task force, the resulting battle probably would have been disaterous. The Japanese at this point in the War were not only better trained, but flying superior aircraft types. And the Americans still were not able to coordinate multi-carrier attacks. (This defincy was still apparent at Midway.) Enterpise aircraft did find and sink the Japanese subnmarine I-70. After determining that the Japanese had departed, Admiral Nimitz had to devise a war plan for the Pacific's fleet's only remaining substantial force--the carriers (Enterprise, Lexington, and Yorktown). Nimitz had to prepare opperational plans with the understanding that new carriers could not be built and reach the fleet until 1943. Loss of the carriers would nean the Imperial Navy would totally dominate the Pacific and even cut off Pearl. The result was a decession not to risk using the carriers in a massive naval battle with the Imperial Fleet, but rather to carry out a series of swift, small-scale hit-and-run raids in the South Pacific. These raids were designed to disrupt Japanese buildups in islands from which anoher attack on Pearl could be staged. In addition, it would give the carrirs and the air groups aboard them the opportunity to practive their skill and operational effectiveness before taking on the Imperial Fleet. The Japanese occupied with carving out their Southeast Asian empire gave the Americn carriers the time needed to become more effective fighting machines. The Enterprise battle group commanded by Admiral Halsey hit the Marshalls (Wo Chi and Kwajeleen) (February 21). Then Enterprise hits Wake Island and Marcus Island. These raids were not without risk, bringing carriers wthin the range of land-based aircraft. The Pacific fleet's carrirs, however, emerged from these operations much more effective and capable fighting ships.
One of these least noted naval campaign was the Indian Ocean engaements during early 1942. Admiral Nagumo with the First Air Fleet entered the Indian Ocean with a force of five carriers and four fast battleships as well as cruisers and destroyers (March 26, 1942). The purpose appears to have been to support Army operations in Burma and escort a convoy to Rangoon and then strike the Btitish naval base in Ceylon (Sri Lanka) where the Royal Navy had been building a substantial naval force. Incredibly this was a larger carrier force than deployed two months later against Midway. The force succeeded in sinking the British light carrier HNS Hermes, two cruisers, and smaller ships. The Royal Navy was asonished with the power of the Japanese carrier force. At this stage of the War, the Japanese carrier aircraft were far superiir to the British carrier aircraft. After the engagement the Royal Navy retired from the eastern Indian Ocean. It is unclear what the value of this campsign was. At the time the only creditable threat to Japan was the badly mauled American Pacific fleet and its four priceless carriers. Any assessment of the military situation would suggest that Japan should have focused on bringing the Pavific fleet to battle to get at those carriers. It is unclear what the purpose of this powerful firce was. They could have seized Ceylon or even attacked British facilities in India. While Nagumo had considerable success against the Royal Navy force, the Royal Air Force from bases in Ceylon had down or damaged a substantial number of Japanese planes. Nagumo had dispersed the British threat, but the American Pacific fleet carriers were still a threat and the British had impaired the combat effectiveness of the First Air Fleet
The news from the Pacific was an unrelenting series of disasters. America needed a victory. The only intact offensive force in the Pacific was Americais carriers. Army Air Corps pilot with B-25s trained for carrier take offs. The B-25 was a medium bomber never intended for carrier use. Carrier commander Afm. "Bull" Halsey led a taskforce made up of Hornet and Enterprise. It was a risky operation as it committed half of the Pacific fleet's carrier force to a very dangerous operation. The B-25s took off from Hornet. It was the first blow to the Japanese home islands. The raid was led by Lt. Col. Jimmy Doolittle. The physical damage was inconsequential, but the psychological impact was immense. Most of the Amrican aviators crash landed in China and were helped to reach saftey by Chinese Nationalist guerillas. The Japanese reprisals were savage. A estimated 0.5-0.7 million Chinese civilians were murdered. The Japanese Navy was so embarassed that they rushed forward Admiral Yamaoto's plans to complete the job left unfinished at Pearl. Yamamoto conceived a plan that would bring the desimated American Pacific Fleet to battle at Midway Island and use the Imperial Fleet's massive superority to destoy it.
The American code breaking effort was designated "Mafic". Magic included breaking both the Japanese diplomatic code and the naval code. At the time of Peal Harbor the Americans were reading the diplomatic, but not the naval code. Although American code breakers did not prevent the attack on Pearl Harbor, as American code breakers cracked the naval code it played a key role in the 1942 naval engagements in which the Japanese held vastly superior naval forces. Commander Joe Rochefort played the critical role in the code breaking effort. [Schom] The results enable the U.S. Navy to turn the Japanese back in the Coral Sea and defeat the Japanese at Miday--ll accomplished with inferior naval resources. A side benefit of Magic was that knowledge of the diplomatic code enabled American code breakers to read transmissions from the Japanese Embassy in Berlin. This provided detailed reports about fighting on the Eastrern Front, information the Soviets were reluctant to supply.
The first important Allied effort to stop the Japanese sweep through the Pacific occurred in the Coral Sea. The Japanese planned to seize Port Moreseby, completing their conquest of New Guinea and a smaller operation in the Solomons at Tulagi. Port Moresby would have provided a launching pad for an invasion of Australia itself. (At the time, most of the Australian Army was in North Africa fighting Rommel's Afrika Korps.) The Japanese landing force was escorted by the front-line carriers Shokaku and Zuikaku. The Japanese naval task force en route to seize Port Moresby was intercepted by an American carrier force, alerted by American code breakers. It was the first carrirer to carrier engagement in history. The Japanese launched an attack on the Americans, but found only a destroyer and oiler. In the meantime the Americans sank the Japanese light carrier Shoho (May 7). The next day the two carrier forces fought a major engagement. The Japanese succeeded in sinking Lexington and heavily damaging Yorktown (May 8). The Americans heavily damaged Shokaku and devestated the air crew of Zuikaku. The substantial Japanese pilot casualties was very signigicant. Despite the American losses, the Japanese invasion force turned back, the first major Japanese reversal of the War. The Japanese assessment of the battle was that not only was Lexington sunk, but that Yorktown was either sunk or so badly damaged that it could no longer be deployed. This affected planning for the Miday operation. The engagement appears to have convinced Japanese naval planners that the American carriers were no mach for the Japanese carriers. The Japanese failed to preceive that the American carriers effectively fought the battle or that the surprise appearance of the American carrier in the Coral Sea to oppose the invasion of Port Moresby resulted from American code breaking. It also meant that they had lost a carrier, and large numbers of planes and pilots. This effectively removed two front line carriers from the Japanese order of battle. This reduced the available carriers for the Midway operation. Combined with the British damage to the First Air Fleet in the Indian Ocean, Admiral Yamamoto had allowed their carrier forces to be significantlseriously weakened in operations of marginal importance. This was critical because if Japan was to win the War it had to be done in 1942 when they had overwealming superiority in the Pacific. If the War developed into a war of attrition, the far greater indusstrial resources of the United States would prevail.
Admiral Yamamoto planned the Midway Opeation as a war-winning stroke. He asseembled the most powerful force in naval history, up to that time. It outclassed the Pacific Fleet in every ship type. What Yamamoto did not understand was that fighting the battle with only four of its first-line carriers and off Midway, the Americans would actually muster more aircraft than the Japanese. Thus Yamamoto was actually creating the circumstance in which the Americans could establish a locallized superiority in air power. Midway proved to be the turning point of the Pacific War. It is notable because it was the only major Allied victory in which the opposing forces were superior. Admiral Yamamoto was determined to bring the American Pacific fleet to battle before America's industrial might could redress the strategic ballance. Yamamoto reasoned that Midway was an assett of such importance that Nimitz would have to commit his few remaining assetts to defend it. The Japanese had many advantages. Unknon to them, however, surprise was not one of the advantages. The same American code breaking operation that had learned of the Port Moresby operation also warned Admiral Nimitz that the next target was Midway. Admiral Yamamoto was convinced that the remaining American carriers could be brought to battle and destroyed at Midway. The Japanese plans were based on achieving an element of surprise and on the fact that two American carriers had been destoyed in the Coral Sea, in fact the Yorktown, although heavily damaged had not been sunk. American code breakers had alerted the Americans to the Japanese plans. Admiral Nimitz positioned Enterprise and Hornet, along with the hastily patched up Yorktown northwest of Midway to ambush he Japanese. The American carrier victory at Midway dealt a crippling blow to the Imperial Navy. The Americans sank four first-line Japnese carriers, killing most of the well-trained crews. The weakness of the Japanese in fire saftey and fire supression was notable. While the Imperial Navy still held an advantage, it was no longer an overwealming one. Meanwhile American shipyards were turning out the new Essex class carriers that would engage the weakened Imperial Navy in 1943. The stunning American carrier victory at Midway, significantly reduced the strike capability of the Imperial Navy.
The Japanese had in a remarkably short period of time seized most of the territory that they had set out to obtain with the resiurces they coveted. And they had done so with relatively limited losses. Holding that territory and supplying the military units posted to hold and exploit the expansive new empire, however, proved to be a much more difficult undertaking. This required both naval vessels and a large maritime (maru) fleet. The Japanese maru fleet was adequate for peace time, but not for war and servicing their expabded new empire. The disaster at Midway significantly changed the military balance. It meant that further offensives would be contested with comparable forces and that existing positions were now open to attack. The Imperial Navy, however, did not aprise the Army of the dimensions of the Midway disaster. And Navy planners still believed they had the capability of destoying the American Pacific Fleet. Most of the Japanese Army was deployed in China. Units could be redeployed to the Pacific, but transporting and supplying them would further stress the capabiity of the Japanese maru fleet. One author describes the Japanese dilema, "The Imperial Navy had 132 Pacific island bastions assigned to the Yokosuka South Seas District, 27 stations assigned to the Kure District, and 23 to the Sasebo District." And all this did not include the forces bogged down in China and Manchuria as well as recntly committed to Malaya, Burma, and Indo-Chinathe, Philipppines, Borneo, and Dutch East Indies. All these forces had to be supplied by the maritime (maru) fleet. Japan did not have sufficet tonage to do this. [Jersey, p.9.] And this was even before the American submarine campaign had begun to effectvely target Japanese shipping. Major World War II battles in Europe were massive undertakings. The Pacific War was different. Major battle were fought by a handfull of divisions. Given the siuze of the islands and the limitations of supplying these island bastion, the Japanese were limited in the forces they could deploy. Thus major engagements which would determine the fate of the Empire, such as the battle for the Mrinas, were fought out by a relatively small force.
After Midway the focus of the War shifted south. America had reduced the Japanese naval advantage, but did not yet have the naval assetts needed to chalenge the Imperal Fleet in a major fleet action in the Central Pacific. The Japanese with a badly-damaged Fleet Air Arm declined to renew challenge the America Pacific Fleet. Both sides instead began to regroup and rebuild their naval forces for a future show down in the Central Pacific. This was a serious mistake for the Japanese as time was on America's side. The tremendous industrial capacity of the United States could build naval vessels and aircraft at a far more rapid rate than Japan. Japan did renew its offense in the South Pacific which had been put on hold after the Coral Sea Battle. This was a natural development because the Japanese after taking the Dutch East Indies had seized almost all of New Guinea, except for Port Moresby and the island groups to the East, including New Britain, New Ireland, and the Solomons. Unlike the Central Pacific, these were large islands (especially New Guinnea) and lcated close together. Thus the fighting could be suported with air fields rather than carriers. Thus the fighting was largelky land operations intersperced with short range amphibious operations. The inintial phase of the campaign was Japanese assaults on Australia, bombing runs, a land offensive crossing the Owen Stanley Mountains to take Port Moresby, and building an air field on Guadacanal in the southern Solomons. This airfield could be used to support naval opertions to cut off Australia from American reinforcements and supplies. The center of the Japanese operations was the vast complex of military instalations the Japanese built at Rabaul on New Britains. The Japanese based their best pilots and planes there. The first American offensive of the Pacific War occurred when U,S, Marines seized the airfield the Japanese were building on Guadalcanal (August 1942). What followed was one of the most prolonged campaigns foughht by the Marines in the War and a series of pitched battles in in the Slot formed by the Solomon Islands. The subsequent Allied offensive was a two prong movement. The first prong was overseen by the U.S. Navy (Halsey) in the Solomons and other islands east of New Guinea. The Navy decided against a costly assault on Rabaul itself. Rather they established rings around Rabaul, cutting off the powerful base and making it impossible for the Japanese to resupply it. They subjected Rabaul to a whithering air assault. Allied troops on Los Negros in the Admiralty Islands played a major role in cutting off and neutralizing Rabaul (December 1943). The second prong was overseen by the U.S. Army (MacArthur) with Australian support. The Australians stopped the Japanese short of Port Moresby. American infantry began taking bases along the northern coast of New Guinea. MacArthur's goal from the beginning was to obtain bases from which he could return to Philippine Islands. Bases in New Zealand brought the southern Philippine Islands into range.
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. Naval aviation has two components, the planes and the pilot who flew them. Only three countries (America, Britain, and Japan) built and deployed carriers. The Germans had plans to do so, but military reverses prevented them from doing so. The carrier aircraft that fought in the Pacific are some of the most storied aircraft of World war II. The Japanese began the War with the most effective carrier aircraft, especially the elegant, but lightly armored A6M Mitsubishi Zero (1941). 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 trasined with 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 new Navy F4U Corsair and F6F Hellcat, combined with the Army Air Corps USAAF P-51 and P-47 fighters devestated Japanese planes. The Japanese fought the entire war with the same basic planes they began the War with, one of many examples of the limited industrial capability with whjivh the Japanese fought the War.
The smll force of American carriers and epecially the victory at Midway provided the time for American industrial capacity to build a naval force with which Japan's limited industrial capacity could not cope. The Japanese built 10 additional by 1945, but the Americans built over 150 carriuers. American shipyards had a substantial capacity, but the American ability to produce ships of all descriptions not only astonished the Japanese and Germans, but it surprised American naval planners as well. The reason was the innovative ship building methods developed by Henry Kaiser and others to produce the Liberty Ships.
While the German submarine campaign in the North Atlantic failed, the American submarine campaign in the Pacific proved spectacularly successful. Hampered by ineffective torpedoes in 1942, the American submarines by 1943 began to significantly affect the delivery of raw materials to Japan. The American submarines targeted the Japanese merchant marine (maru) fleet. While the big fleet carriers got the headlines. The American submarines sunk over 50 percent of all vessels destroyed during the War. The Japanese merchant marine was almost completely destroying, cutting the country's war industries off from supplies and bringing the country close to starvation by 1945. The American submarines did to Japan what the German u-boats tried to do to Britain. Surprisingly the Japanese submarine fleet had little impact on the Pacific campaign. Unlike the Americans, the Japanese began the War with the effective Type 93 Long-Lance Torpedo. The Japanese Navy never used their submarines to interdict American supply vessels. Rather they were used to target fighting ships with only limited success because of their tactical deployment. The Japanese used their submarines as scouts and to targer warships. As the American offensive moved toward the Home Islands, the Japanese used their submarines to supply bypassed island garisons, some of which were near starvation. They were also used to supply bypassed island bases where many garrisons were close to starvation. They also managed to get some secret German military technology to Japan late in the war (1944-45).
While MacArthur and the Army drove fowad in New Guiena, the Navy achieved most of its objectives in the South Pacific/Solomons. Rabaul was not taken as had been planned with Operatioin Cartwheel, but it was neutralized. And the Imperial Navy's pilot forcehad been drained to support air operationd from Rabaul. The Navy next began a new offensive drive in the Central Pacific. Amercan industrial strength by now was producing ships and planes that enabled America to build a naval force capable of leap froging from island to island. The Japanese had gambled when they struck Pearl Harbor. They believed that Americans were morally weak and would not fight. Guadacanal and Tarawa showed that they were very wrong. And now they faced the most powerful industrial power in the World which they had roused to a nation demanding retribution. Worse still there German allies were falling back on all fronts. Japan would be left to fight both American and Britain alone. Unlike the Solomons campign, the Imperial Navy did not contest the American advance cross the Central Pacific. The Combined Fleet even withdrew from Truk, its primarit Central Pacific bastion. Only when the Americans assalted the Marianas did the Imperial Navy sally forth. The Marianas were the key to the War. The new American B-29 could reach the Japanese Home Islands from the Marianas and the Japanese knew it. The result would be the epic Battle of the Phillipnes Sea. The Imperial Navy had been preparing for the battle for 2 years. The result shocked the Empire to its core.
The two American offensives in the Pacific came to a conclusion at the same time. The U.S. Army under Douglas MacArthur in the South Pacific had neutrilized Rabaul and defeated or bypassed Japanese forces in the Solomons and northeastern New Guinea. At the same time, the U.S. Navy under Admiral Chester Nimitz after driving through the Central Pacific (the Giberts and Marshalls) and finally seieed the Marianas after the great naval victory in the Philippines Sea. But this brought to the fore the still unanwered question of 'where next?' There were two targets on the table. MacArthur was adament about the answer--the Philippines. Since departing Corrigedor he had repeated his goal, 'I shall return.' His argument was largely political and moral--we owed it to the Filipino people as the Philippines at the time was American territory. Admiral Earnest King believed that Formosa (Taiwan) made more strategic sense, largely because it would more more effectively interdict the delivery of raw materials from the Southern Resourse Zone to the Home Islands. A difference of such magnitude between such senior American commanders could only be resolved by President Roosevelt. The President summoned his commanders at Pearl Harbor, Hawaii to settle the issue of the direction of the advance on Japan (July 26-27). MacArthur made his and the Army's case. Nimitz made the case for the Navy. The choice would be the Philippines leading to the greatest naval battle in world history--the Battle of Leyte Gulf.
The Battle of Leyte Gulf was the greatest naval battle in history. It was the last engagement where opposing battleships faced each other. It was a desperate action by Japan which essentially pitted its battleships against American carriers. Japan had begun the war with a stratgy based in carrier warfare, but by 1944 the Imperial Navy was firced to rely on its battleships against an overwealming american carrier force. The Battle for Leyte Gulf occurred October 23-26, 1944. The Japanese drew up a highly complex strategy to throw virtually the entire remaining Imperial fleet in a desperate attempt to oppse the American invasion of the Philippine Islands. The battle evolved in four separate actions thayt both side found difficult to coordinate in the furious battles that ensyed. Once the American landings at Leyte Gulf began the Japanese ordered three separate forces to oppose the Americans. The Japanese Cental Force or main force sailed through the Philippines to reach the American landings at Leyte. It was spotted and intercepted by American carrier from Task Force 38. It was mauled in the Sibuyan Sea. The giant Nustachi was sunk. It turned back, but was not destroyed. The Japanese Southern Force tried tried to reach Leyte through the Surigao Strait. They were intercepted by American battleships, some of which had been raised from Pearl Harbor. This proved to be the greatest surface action since Jutland in World War I and the last important action between battleships in history. American destroyers and battleships using radar in a night action virtually wiped out the Southern Force. Next the Northern Force which was a carrier force meant to decoy Halsey's Third Fleet was spotted. Halsey immediately raced to engage this force. It was descimated in an engagement off Cape Engano. Meanwhile the Japanese Central Force had turned around and was approaching Leyte Gulf. Unprotected by the Third Fleet, the Japanese would have wreaked hhavic on the troop ships and supply vessels. The only force between Leyte Gulf was a small group of American escort carriers and destroyers. The esort carriets were supporting the landings and protecting the invasion fleet from submine attack. They did not have armour piercing bombs needed for attacks on battleships. Somehow this force managed to turn around the Japanse Central Force in a an action off Samar, although at great cost. After the battle the Imperial Fleet no longer existed as a creditable naval force. [Thomas]
From the onset of the Pacific War, the South China Sea becme essentially a Japanese lake. Japanese merchant vessels brought the resources of the Southeast Asia (Southern Resource Area) through the South China Sea without fear of American interdiction. This only bgan to change in late 1943 when the American sunmarine campaign began to resolve the problems encountered early n the War, but Allied surface ships still could not operate in the South China Sea through 1944. This finally changed in 1945, in part because of the deterioration of Japanese naval and air power after the Battle of Leyte Gulf and in invasion of the Philippines (October 1944).
Task Force (38) was one of the most powerfull naval forces ever assembled. It was tasked with supporting the Luzon landings at Lingayen. As part of this operation it was tasked with engaging Japanese air fields and naval targets to the east capable of supporting Japanese forces in the Philippines. TF 38 also swept the South China Sea. The retaking of Clark Field and other air bases on the Philippines meant that American carrier groups were now able to enter the South China Sea. TF 38 began with raids on airfields on Formosa (January 3) and for a week hammered other targets. TF 38 entered the South China Sea through the Bashi Channel between Formosa and Luzon (January 10). TF 38 was composed of both Essex Fleet cariers and lighter carriers and support vessels. TF 38 hit Saigon and Tourane Bay, Indochina (January 12). TF 38 destroyed 44 enemy ships including 15 naval vessels as well as many aircraft and military facilities. TF 38 struck Formosa and Canton in China (January 15). Further strikes hit Canton again and Hong Kong (January 16). TF 38 exited the South China Sea through the Balintang Channel, another channel, between Taiwan and Luzon (January 20). They headed north, striking targets on Formosa (January 21) and Okinawa (January 22). TF 38 finally reached Ulithi Lagoon for resupply and refitting (January 26). The Navy South China Sea operation along with the seizue of the Phillipnes and the American submarine campaign meant that Japan was cut off from their Southern Resource Area. Japan launched the War to obtain the resources of Southeast Asia and now those resources were no longer available to the war industries on the Home Islands.
Okinawa was a major land campaign conducted by the Army and Marines. The ininital landings were unopposed, but the Japanese made their stand in the south and the fighting was brutal. The Japanese exacted a terrible toll from carefully prepared defenses. The American landings were largely unopposed by the Imperial Navy which had been desimated at the Battle of Leyte Gulf. The Imperial Navy was no longer capable of a fleet action to oppose the American Navy. The great naval battles of the War were now over. The primary exception was the suiside mission of the Yamato, the remaining Japanese super-battleship. The Yamato had turned around at Samar. This time there would be no turning back. The Yamato was intercepted by American carrier aircraft and sunk after repated hits in a horific bombardment. The Navy's role. however, was critical. Carrier aircraft was needed to provide air support until the land needed for air bases could be seized from the Japanese and airfilds established. Also the Navy was needed for logistical support, landing the assault troops and then supplying them. This meant the Navy had to bring its ships into range of Japanese lnd-based aircraft. The Japanese mounted a major Kamakazee campaign against the American ships off Okinawa. The Japanese aircraft were for the most part the same aircraft that the Japanese had begun the war with. Most of the well-trained pilots were gone. Japan would conduct its Kamakazee campaign with obsolete air craft and virtually untrained pilots, butlaunched in mass, some could get through. The Kamakazee was the lone effective weapon that could strike at the American invasion fleet. The success on Okinawa was fully understood by the Japanese and was to be the basis for the defense of the Home Islands. They assembled a secret air force of 5,000 planes to be used in a massive Kamikazzee attack on the llied invasion fleet.
American pre-War naval plnning envisioned a climatic naval action with big gun battleships to win a war in the cPacific. Immediately after Pearl Harbor, the United States attempted to launch a commerce war against the Japanese. Japan like Britain was an industrial island natiin which had to import both food and raw materials. Oil was particularlyb important because there is almost no domestic production. One might ask why a nation so vulnerable woukd launch a naval war against an industrial giant, but the Japanese obsession with winning the war in China and seizing the Southern Resource Zone (SRZ) was so intense tht the Japanese military decided to gamble. A commerce war against Japanese merchant shipping (marus) was an obvious naval strategy. And Japan had begun the War with an inadequate merchant fleet. The demand of supplying its nely seized, far-fling empire put a grear srain on the fleet. Admiral Nimitz was an old submariune commander and the submarines were one of few naval ssetts available. Faulty torpedoes, however, rendered early sunmarine actions ineffective. This problem was not completely resolved until 1943 and it is at this time tht the Americans submriners began to seriously impact the maru fleet. They were assisted by Ultra intercepts. The destruction of the Imperial Navy in the Battles of the Philippines Sea and Leyte Gulf left the Japanese powerless to keep sea lane open except for coastal shipping. Japan had the needed resources in the SRZ to continue the War, but no way of getting those resources to the Home Islands. It is at this time that the U.S. Navy surface fllet and aircraft in firt the Philippins and then Okinawa joined the submarines tightened the blockade of the Home Islands. The next step was the Strategic boming campaign which hammered Japanese ports. Carrier aircraft and land based planes from Iwo Jima and Okinawa commenced low-level attacks which hit small craft including fishing boars and barges. The final step was dropping aerial bombs which left all the major ports inperable even if ships slipped through the blockade. This completed the blockade and left the Japanese despertely short of food and facing a poor 1945 harbests. Civilians were put to work collecting acorns. Food rations were cut to subsistence levels. The few war plants that somehow survived the bombing were brought to a hault because of the shortage of raw materials. Some of the last reserves of petroleum were used to create the fuel needed for axlast desperate Kakikazze attack aimed at the Allied invasion fleet. There was not even suffucent fuel to properly train new pilots.
America ended the warby dropping two atomic bombs were dropped (August 1945) and Japan finally surrendered (September 1945).The American Manhattan Program was initiated by President Roosevelt when work done by German physicists led to concern that the NAZIs might build an atomic bomb. Jewish and oher refugees fleeing the NAZIs made a major contribution to the success of the Manhattan Program. The first bomb was successflly tested at Alamagordo, New Mexico on July ??, 1945. The Allies met in a Berlin suburb after the NAZI surrender to make dcisions about the occupation of Germany and defeating Japan. The Allied powers 2 weeks after the bomb was tested demanded on July 27, 1945 that Japan surrender unconditionally, or warned of "prompt or utter destruction". This became known as the
Potsdam Declaration. The Japanese military was prepared to fight on rather than surender. The Japanese Government responded to the Potsdam Declaration with "utter contemp". The Japanese military continued feverish pland to repel the Ameican invasion of the Home Islands. Many Whermacht generals at the end of the War were anxious to surrnder to the Amreicans. One German General commanding forces west of Berlin after the War said, "We wondered why they didn't come." This was not the attitude of the Japanese military. I know of know memoir written by an important Japanese military officer expresing similar sntiments. Truman was not anxious to use the atomic bomb. He was anxious to end the War and limit Ameican casulties. For Truman the Japanese response to the Potsdam Declaration made up his mind. There have been many books and aticles published in both Japan and America about the atomic bomb. Japanese scholars have reserched the decission making process that led to the dropping of the atomic bombs. Almost always the focus is on Truman and
Ameican military leasers. Rarely do Japanese authors address the role of Japanese political and military leaders. The United States dropped two atomic bombs on Hiroshima and Nagasaki on August 6 and 9, and the Soviet Union entered the war against Japan on August 8.
Freidel, Frank. Franklin D. Roosevelt: Rendezuous with Destiny (Little Brown: Boston, 1990), 710p.
Jersey, Stanley Coleman. Hell's Island: The Untold Story of Guadalcanal (Texas A&m: College Station, 2008), 514p.
Schom, Alan. The Eagle and the Rising Sun: The Japanese-American War 1941-1943 (Norton, 2003).
Thomas, Evan. Sea of Thunder: Four Commanders and the Last Great Naval Campaign, 1941-1945 (Simon & Schuster: New York, 2006), 414p.
Navigate the CIH World War II Pages
[Return to Main Pacific War land campaign]
[Return to Main World War II naval campaign page]
[Biographies] [Campaigns] [Children] [Countries] [Deciding factors [Diplomacy] [Geo-political crisis] [Economics] [Home front] [Intelligence]
[Resistance] [Race] [Refugees] [Technology]
[Bibliographies] [Contributions] [FAQs] [Images] [Links] [Registration] [Tools]
[Return to Main World War II page]
[Children in History Home]