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World War II

World War II was the largest and most violent armed conflict in human history. The Second World War, a protracted, total war fought for unlimited aims, was a global struggle between two powerful coalitions. For six years, the war unleashed atrocities on a scale never before seen, including the annihilation of six million Jews in Nazi death camps. Before it was over, more than 60,000,000 people lost their lives. And the world entered the nuclear age when the United States dropped two atomic bombs on Japan in August 1945.

Three events helped usher in World War Two: Japan overran Manchuria; Italy, under fascist dictator Benito Mussolini, invaded Ethiopia; and - most important -- Adolf Hitler came to power in Germany. He rearmed the country, in violation of a treaty signed after World War One, and soon began to threaten other European nations. Arrayed against these powers were, principally, Britain, France, the Soviet Union and, later, the United States.

While Hitler's Germany advanced in Europe, Japan brought on the Greater East Asian War in the Pacific by its expansion in East Asia. A clique of aggressively militaristic officers and politicians gained control of the government during the 1930s. The goal of Japan's leaders was to create an empire that dominated the countries of East Asia and the sea lanes of the Western Pacific. The road to war between Japan and the United States began in the 1930s when differences over China drove the two nations apart. In 1931 Japan conquered Manchuria, which until then had been part of China. Japanese forces invaded China in July 1937, leading to a full-scale war which the Japanese military had neither expected nor desired. The Japanese war with China continued longer than the Japanese had expected, as Japan became mired in the vastness of China.

American strategic planning after WWI was largely conditioned by a popular reaction against war. Most military planning was theoretical, and Great Britain had the power to challenge the US. War Plan Orange was a paper plan to contain the Japanese in the Pacific by harassment and isolation. The U.S. Pacific Fleet in theory could win a war. The role of the Army would be to fight a delaying action until the Navy arrived. Later the Red Plan came into being, the possibility of a war with Great Britain and the need to defend the Panama Canal and the Western Hemisphere. The thinking was that the Northeastern United States was the most important section, thus the Atlantic Fleet should be the stronger. A two-ocean navy was needed more than a strong army. The Joint Planners, as a result of aggressive acts on the part of the Axis Powers, developed the Rainbow Plan which assumed Great Britain, France and the United States would act in consort to stop the Axis Powers. With the increasing tensions in Europe and Asia, during the late 1930s the War and Navy Departments in the United States had developed a series of contingency plans for fighting multiple enemies, known as the "RAINBOW" plans. The final revision, RAINBOW 5, emphasized the role of the Air Corps in frontier air defenses and air power projection. The Rainbow Plan was not a plan of operations, it merely outlined the objectives and missions of American forces in case of war.

The war that is now called the Pacific front of World War II was called in Japan the Great East Asia War, for the liberation of Asia from the European and American colonizers was the proclaimed Goal. In July 1940, Japanese Minister of Foreign Affairs Matsuoka Yosuke stated the Japanese foreign affair policy as "to establish the Greater East Asian Co-Prosperity Sphere, with Japan-Manchuria-China line as its core." In September 1940 Japan concluded the Tripartite Pact with Germany and Italy, and the Russo-Japanese Neutiality Pact in 1941.

The slogan The Greater East Asian Co-Prosperity Sphere proclaimed the idealism of pan-Asiatic prosperity, but for the Japanese government it was also part of their strategy, entering into alliance with Germany and Italy to break the deadlock situation in the war with China, and to expand toward South East Asia to acquire its rich natural resources in lands where the control of the European colonizing powers had weakened their influence because of the war in Europe. The majority of the Japanese people embraced the idealism of The Greater East Asian Co-Prosperity Sphere, and justified their government's policy for the expansion southward.

The United States, which had important political and economic interests in East Asia, was alarmed by these Japanese moves. The US increased military and financial aid to China, embarked on a program of strengthening its military power in the Pacific, and cut off the shipment of oil and other raw materials to Japan. Because Japan was poor in natural resources, its government viewed these steps, especially the embargo on oil as a threat to the nation's survival. Japan's leaders responded by resolving to seize the resource-rich territories of Southeast Asia, even though that move would certainly result in war with the United States.

The prospects for an Axis victory led the United States to take its first tentative steps toward direct involvement in the war. In September 1940, President Franklin Roosevelt approved the transfer of 50 destroyers to Britain, in return for a lease on British bases in the Caribbean. That September, the United States initiated a peacetime Selective Service and a partial mobilization of the National Guard. In December 1940, Roosevelt announced the United States would provide military supplies to Britain under a policy termed "lend-lease." The President justified his actions by declaring that the United States must become the "arsenal of democracy." In the summer of 1941, Roosevelt ordered the Navy to escort merchant convoys as far as Iceland. This order resulted in an undeclared war between American destroyers and German submarines, and led to the sinking of the destroyer Reuben James by the Germans on 31 October 1941.

Historians of America's total military and logistic effort in World War II may well agree that the eighteen months of preparations before Pearl Harbor played a crucial, if not decisive, part in the outcome of the war. During this period the Military establishment of the United States was rehabilitated and the foundation laid for America's tremendous war production achievement. The RAINBOW plans were the war plans to defeat Italy, Germany and Japan. RAINBOW V, the plan in effect on 7 December 1941 when Japan attacked Pearl Harbor, was the plan the US used to fight the Axis powers.

World War II affected Americans on the home front in ways that varied from the selection of movies to rationing of consumer goods. A crucial element of the home front effort was the mobilization of resources in support of the fighting forces. The tremendous mobilization of resources made the Allied victory possible. Mobilization included the training of personnel, and the production of weapons, ammunition, and equipment. These activities required an extensive domestic construction program to build the facilities necessary to train and equip the Allied forces. The military of the late 1930s lacked the materiel readiness to fight a sustained war, especially using the blitzkrieg tactics of World War II. The requirements for supplying materiel to Britain and the Soviet Union further amplified the challenges of industrial production.

Type 1940 1941 1942 1943 1944 1945 Total
Very Heavy Bombers 0 0 4 91 1,147 2,657 3,899
Heavy Bombers 19 181 2,241 8,695 13,057 3,681 27,874
Medium Bombers 24 326 2,429 3,989 3,636 1,432 11,836
Light Bombers 16 373 1,153 2,247 2,276 1,720 7,785
Fighters 187 1,727 5,213 11,766 18,291 10,591 47,775
Reconnaissance 10 165 195 320 241 285 1,216
Transports 5 133 1,264 5,072 6,430 3,043 15,947
Trainers 948 5,585 11,004 11,246 4,861 825 34,469
Communication/ Liaison 0 233 2,945 2,463 1,608 2,020 9,269
Total by Year 1,209 8,723 26,448 45,889 51,547 26,254 160,070
In January 1939, President Roosevelt was already aware of the relative weakness of the Army's air arm. He advocated an immediate expansion of the Air Corps to bring it in line with the air forces of rival powers. In April 1939, Congress responded with an authorization to expand the Air Corps to 6,000 aircraft. In mid-1940, as Hitler's blitzkrieg rumbled through France, Roosevelt had called for a 50,000 plane Air Corps supported by production levels of 50,000 planes per year. It was clear to Army Air Forces leadership that a massive expansion would be necessary for US air power to play the decisive role it anticipated for itself in World War II.

Immediately after the fall of France in June 1940, the Navy also initiated an expansion program. On 19 July 1940, less than a month after the French surrender, Congress authorized the acquisition of 13 battleships, 6 aircraft carriers, 32 cruisers, 39 submarines, and 101 destroyers. The carriers were of the Essex variety, which constituted the backbone of the Pacific fleet in the forthcoming war. The increased number of ships was accompanied by a comparable expansion of shore facilities.

Though the conversion to wartime production in 1940 and 1941 provided a transition to declared war, even greater efforts were required after the United States entered the war. The industrial mobilization process begun during the protective mobilization phase intensified until the United States could overwhelm the Axis powers with its material resources.

Despite the shortages of raw materials, American industry soon began the transition to wartime production. Automobile factories converted their production lines to military vehicles, and other factories made similar conversions. Where existing facilities were unsuited for munitions production, new factories or shipyards were constructed to meet the production requirements. As the war progressed, the logistical advantages of the United States provided a crucial edge to the Allies. As the Axis powers gradually lost their war production capabilities to Allied bombing, the Allies increased their capabilities until the final defeat of Germany and Japan.

The ability of the United States to project its power depended on sea control. In the Atlantic, Britain and the United States faced a serious threat from German submarines. This threat called into question the ability of the Grand Alliance to bring about the complete defeat of Nazi Germany. By working closely with the navies of Britain and Canada, by building large numbers of merchant vessels and warships, and by devising innovative methods and new weapons for antisubmarine warfare, the United States contributed to Germany's defeat in the so-called Battle of the Atlantic. Allied victory in the Battle of the Atlantic was a precondition for the defeat of Germany.

The scope of the American contribution to the war against Germany and Italy started modestly and grew to enormous proportions. At the beginning of the North African invasion, the United States could provide only one corps. By the close of the war, six numbered American armies operated in western Europe, although the Fifteenth Army was not organized until the end of the war. Americans provided 61 of 91 Allied divisions in the western Europe theater of operations, plus 7 of 18 divisions in Italy. Four of the six Allied tactical air commands were American. Even these figures do not represent the full American contribution to the Allied victory. The United States provided ammunition, equipment, and other essential military supplies to British and Russian forces.

The Japanese military, deeply engaged in the seemingly endless war against China, badly needed oil and other raw materials. Commercial access to these was gradually curtailed as the conquests continued. The Japanese continued their expansion, and entered French Indochina in 1941. The United States responded with an embargo which made Japanese shortages of oil and raw materials even more acute as the war in China continued without resolution. In July 1941 the Western powers effectively halted trade with Japan. From then on, as the desperate Japanese schemed to seize the oil and mineral-rich East Indies and Southeast Asia, a Pacific war was virtually inevitable.

By late November 1941, with peace negotiations clearly approaching an end, informed U.S. officials (and they were well-informed, they believed, through an ability to read Japan's diplomatic codes) fully expected a Japanese attack into the Indies, Malaya and probably the Philippines. Completely unanticipated was the prospect that Japan would attack east, as well.

The Japanese attack on Pearl Harbor on December 7, 1941, abruptly ushered the United States from defense to war and united Americans in a determination to defeat the Axis powers. The justificatory aim of the attack according to Japanese pronouncements was to liberate Asia from the colonial domination of the great American and European powers. American military planners had to make an important decision when the US entered the war. The country could not fight effectively at the same time in both Asia and Europe. It was decided to use most of American forces to defeat the German troops of Adolf Hitler. A strategic defensive was maintained in the Pacific until success in Europe permitted the transfer of forces to the Pacific for an offensive against Japan. This decision had important results, as Japan was able to win many of the early battles of the war in Asia.

The memory of the "sneak attack" on Pearl Harbor fueled a determination to fight on. Once the Battle of Midway in June 1942 had eliminated much of Japan's striking power, that same memory stoked a relentless war to reverse her conquests and remove her, and her German and Italian allies, as future threats to World peace.

Japan's industrial potential was approximately ten percent of that of the United States, and was always hampered by a lack of oil. Even though her research and technical design work was not purely imitative, Japan's ability to develop reliable operating equipment in the new fields was low. Japanese radar and communications equipment was weak. Japan could not build sufficient ships or escort vessels, and lacked construction equipment to build adequate airfields. Japan could not economically afford to build adequate shelters for her population, and could not both disperse her industry and also repair damaged plants. Japan chose dispersal rather than repair, but had insufficient means even to disperse effectively.

From February 1942 until July 1944, a war of attrition was fought by the air forces of the United States, Australia and Japan in Papua, New Guinea, the Bismarck Archipelago and the Solomon Islands. Although this period comprises more than half the length of the war in the Pacific, somehow more attention seems to be paid in popular histories to other aspects of that war, such as the actions of the carrier fleets of Japan and the United States. The air campaign in the South Pacific, however, was of extreme importance, not just to the persons of all sides who fought there, but to the outcome of the war. This is because it was in, over and around the island of New Guinea that the Japanese Army and Navy, and their air forces, were first stopped, worn down and finally pushed back.

The United States entered the Second World War with a Germany-first strategy. By 1943, however, American forces were on the offensive against both Germany and Japan. American military planners did not agree about the best way to launch such a counterattack. Admiral Nimitz of the navy wanted to capture the small groups of Japanese-held islands in the Pacific, then seize Taiwan, and finally attack Japan itself. But General Douglas MacArthur of the Army thought it best to attack through New Guinea and the Philippines.

The American leadership finally decided to launch both attacks at once. Plans to launch an offensive against the Japanese in the islands of the Pacific were initiated in 1943 at the Quadrant Conference held in Quebec. The American counter-offensive advanced along two axes. American forces under General Douglas MacArthur or Admiral William Halsey advanced along a southern route towards the Philippines. Meanwhile, other forces under Admirals Chester Nimitz and Raymond Spruance moved toward the Gilbert Islands, then the Marshalls, followed by Wake, the Eastern Carolines, and finally the Marianas. Both Nimitz and MacArthur succeeded. Allied military leaders found a way to defeat the Japanese, by avoiding the islands where the Japanese were strong. But sometimes the allies could not avoid battle, as they had to land on some islands to seize airfields for American bombers.

The war termination strategies adopted by the United States remain controversial despite the passage of more than fifty years. Germany and Japan were determined and resourceful adversaries. Bringing about their complete defeat, while holding down American casualties and managing the United States' relationships with allies, posed difficult strategic choices for American decision-makers. Nothing better illustrates these difficulties than the decision to use nuclear weapons to force Japan's surrender.

Suddenly, sooner than expected, the war ended. On 2 September 1945 World War II ended when representatives of Japan signed the instruments of surrender aboard the battleship USS Missouri (BB 63) in Tokyo Bay. More than twenty-five-million soldiers and civilians had died during the six years of fighting. Germany and Japan were defeated. The Soviet Union was strong in much of Eastern Europe. And the United States found it had become the world's strongest military, economic, and political power. World War II was a watershed in the history of the Uinted States. Wartime developments in science and technology provided new tools for the solution of prewar problems that had been put aside and new ones created by the exigencies of the war. The contribution of science to the security and prosperity of the Nation was more widely recognized than ever before.

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