World History/Causes and course of the Second World War

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Causes of World War II

France, Great Britain, and the U.S. had attained their wartime objectives in 1919. They had reduced Germany to a military cipher and had reorganized Europe and the world as they saw fit. The French and the British frequently disagreed on policy in the postwar period, however, and were unsure of their ability to defend the peace settlement. Disillusionment with war led to the practice of appeasement, or giving into an aggressor's demands to keep the peace. The U.S., disillusioned by the Europeans' failure to pay their war debts, retreated into isolationism. The Treaty of Versailles left many countries dissatisfied. Adverse conditions, such as reparations and unemployed veterans from World War I led to the circulation of new, radical ideas and solutions, such as fascism in Italy. This Fascist party, as Mussolini called it, later became a model for Hitler in Germany.

The Failure of Peace Efforts

During the 1920s, attempts were made to achieve a stable peace. The first was President Woodrow Wilson's idea to establish the League of Nations (1920) as a forum in which nations could settle their disputes. The League's powers were limited to persuasion and various levels of moral and economic sanctions that the members were free to carry out as they saw fit. The United States never joined the League and Germany and the USSR were also never members. At the Washington Conference of 1921-2, the principal naval powers agreed to limit their navies according to a fixed ratio. The Locarno Conference (1925) produced a treaty guarantee of the German-French boundary and an arbitration agreement between Germany and Poland. In the Kellogg-Briande Pact (1928), 63 countries including all the Great Powers except the USSR, renounced war as an instrument of national policy and pledged to resolve all disputes among them "by pacific means." The signatories had agreed beforehand to exempt wars of "self-defense."

The Rise of Fascism

One of the victors' stated aims in World War I had been "to make the world safe for democracy," and postwar Germany adopted a democratic constitution, as did most of the other states restored or created after the war. In the 1920s, however, the wave of the future appeared to be a form of nationalistic, militaristic totalitarianism known by its Italian name, fascism. It promised to minister to peoples' wants more effectively than democracy and presented itself as the one sure defense against communism. Benito Mussolini established the first Fascist, European dictatorship during the inter war period in Italy in 1922.

Formation of the Axis Coalition

Adolf Hitler, the Leader of the German National Socialist (Nazi) party, preached a racist brand of fascism. Hitler promised to overturn the Versailles Treaty and secure additional Lebensraum ("living space") for the German people, who he contended deserve more as members of a superior race. In the early 1930s, the Great Depression hit Germany. The moderate parties could not agree on what to do about it, and large numbers of voters turned to the Nazis and Communists. In 1933 Hitler became the German Chancellor, and in a series of subsequent moves established himself as dictator. Japan did not formally adopt fascism, but the armed forces' powerful position in government enabled them to impose a similar type of totalitarianism. As dismantlers of the world status quo, the Japanese were well ahead of Hitler. They used a minor clash with Chinese troops near Mukden, also known as the Mukden or Manchurian crisis, in 1931 as a pretext for taking over all of Manchuria, where they proclaimed the puppet state of Manchukuo in 1932. In 1937-8 they occupied the main Chinese ports. Having denounced the disarmament clauses of the Versailles Treaty, created a new air force, and reintroduced conscription, Hitler tried out his new weapons on the side of right-wing military rebels in the Spanish civil war (1936-9). This venture brought him into collaboration with Mussolini who was also supporting the Spanish revolt after having seized (1935-6) Ethiopia in a small war. Treaties between Germany, Italy, and Japan in 1936-7 brought into being the Rome-Berlin-Tokyo Axis. For example, Japan and Germany signed the Anti-Comintern pact in 1936 and then Italy joined in 1937. This pact denounced communism and it showed their unity in the matter. The Axis thereafter became the collective term for those countries and their allies.

German Aggression in Europe

Hitler launched his own expansionist drive with the annexation of Austria in March 1938. The way was clear: Mussolini supported him; and the British and French, overawed by German rearmament, accepted Hitler's claim that the status of Austria was an internal German affair. The U.S. had impaired its ability to act against aggression by passing a neutrality law that prohibited material assistance to all parties in foreign conflicts. In September 1938 Hitler threatened war to annex the western border area of Czechoslovakia, the Sudetenland and its 3.5. million ethnic Germans. The British Prime Minister Neville Chamberlain initiated talks that culminated at the end of the month in the Munich Pact, by which the Czechs, on British and French urging, relinquished the Sudetenland in return for Hitler's promise not to take any more Czech territory. Chamberlain believed he had achieved "peace for our time," but the word Munich soon implied abject and futile appeasement. Less than six months later, in March 1939, Hitler seized the remainder of Czechoslovakia. Alarmed by this new aggression and by Hitler's threats against Poland, the British government pledged to aid that country if Germany threatened its independence. A popular joke ran at the time: "A guarantee a day keeps Hitler away". France already had a mutual defense treaty with Poland. The turn away from appeasement brought the Soviet Union to the fore. Joseph Stalin, the Soviet dictator, had offered military help to Czechoslovakia during the 1938 crisis, but had been ignored by all the parties to the Munich Agreement. Now that war threatened, he was courted by both sides, but Hitler made the more attractive offer. Allied with Britain and France, the Soviet Union might well have had to fight, but all Germany asked for was its neutrality. In Moscow, on the night of August 23, 1939, the Nazi-Soviet Pact was signed. In the part published the next day, Germany and the Soviet Union agreed not to go to war against each other. A secret protocol gave Stalin a free hand in Finland, Estonia, Latvia, eastern Poland, and eastern Romania.

The Worldwide Great Depression

The Great Depression lead to a number of social effects across the world, contributing to WWII.

The costs of carrying out World War I, as well as the costs to rebuild Western Europe after years of fighting, resulted in enormous debts on the part of the Western European powers to the United States. The enormous reparations put on Germany in the Treaty of Versailles also increased the debts. Coupled with ineffective governments in many of these European States (notably the Weinmar Republic, pre-Mussolini Italy and Socialist France) led to slow reconstruction and poor economic growth.

With the crash of the New York Stock Market on 29 October, 1929, the United States recalled all foreign loans in the following days. Unable to repay these loans, the economies of the West collapsed, beginning the Great Depression.

War in Europe

Warsaw following German attack.

The German invasion of Poland on September 1, 1939 is regarded as the start of World War II. Due to official League of Nations law, France and the UK were obligated to intervene, but in reality did very little in a period known as the phony war. In Poland, however, fighting had begun. Germany was extremely successful in this war due to their new strategy known as blitzkrieg (meaning "lightning war"). This strategy involved the use of tanks, a relatively new technology at the time, to quickly overrun a country before they could set up their defenses properly. This strategy worked amazingly for Germany, with the German troops arriving near the Polish capitol of Warsaw in just 7 days. Germany and the USSR had made a nonaggression pact in the days leading up to the invasion, which was essentially an agreement to split eastern Europe between the two countries. The agreement was initially a shock to the world, as the two countries were governed by ideologies that were about as far apart from each other as possible. However, this fragile agreement did not last. Before that, though, the USSR used this opportunity to annex the Baltic states, parts of Romania, and tried to take land Finland in a disastrous campaign for the Russians known as the winter war. Germany then proceeded to take out Denmark and Norway in order to secure positions in the north sea. Then Germany shifted their attention to France. French strategy relied on using the Maginot line, a massive line of forts stretching the entirety of their border with Germany to protect their border with relatively few troops while positioning their best forces along the border with Belgium, as Germany had attacked through Belgium in the first world war. However, they left the Ardennes forest undefended, as they believed that the dense forest would provide enough of a natural barrier. Knowing this, Germany launched a daring attack that sent 50 tank divisions through the Ardennes. The Germans broke through, and managed to cut off the allied forces. The French forces there were wiped out, but they were able to defend long enough to let British forces escape through Dunkirk. But for France, all was lost. The bulk of their army had been wiped out, and within weeks France had to surrender. This was far from the end of French resistance, though, as aside from civilian resistance efforts, and forces fighting under the banner of "Free France" played a major role in the north African front in the coming years. In Europe, however, Germany had set up a puppet state called Vichy France in the south, while the north was fully annexed for defense purposes. Germany tried to make the odds seem as far in their favor as they could in the hopes that Britain would try to make peace, but the new Prime Minister Winston Churchill refused to give up. In order to take over the British Isles, Germany would first have to gain control of the English channel in both the air and sea to be able to land troops on the island. After intense air fighting over England that resulted in the bombing of major English cities, Britain stopped any chance of a naval invasion.

The War in the Pacific

• Note that this is only a rough outline. Change it as needed.

Mukden Incident and the Invasion of Manchuria (1931)

Japanese troops during the invasion

After winning the Russo-Japanese War in 1905, Japan quickly became the dominant power in its region. Russia recognized Korea as a Japanese sphere of influence and removed all of its forces from there and Manchuria, the sparsely populated northeastern region of China. In 1910, Japan annexed Korea as its own with little protest or resistance. Still, Japan was a quickly growing country, both population-wise and economically. It founded the South Manchuria Railway company in Manchuria in 1906, and with that company was able to gain government-like control of the area.

By 1931, the Depression had struck a blow to Japan. The government did little to help Japan's economy, and in the eyes of its citizens, was weak and powerless. Instead, the public favored the Japanese army, and soon the civilian government had lost control of its military. To the army, Manchuria seemed like an obvious solution to many of Japan's problems. Manchuria was vast and thinly populated, and would serve as excellent elbow room for an already overcrowded Japan. It was also thought that Manchuria was rich in forests, natural resources, and fertile land. The fact that the Japanese believed themselves to be far superior to the Chinese only moved Japan towards conflict faster. Additionally, the warlord of Manchuria went against Japanese expectations and declared his allegiance to a growing Chinese military movement. So, in 1931, the army staged an explosion at a section of railway near Mukden, a city in Manchuria, as a pretext to invade and annex China. Japan met little resistance, although it did not have support of its own government, and Manchuria was completely occupied by the end of the year. Japan subsequently set up the puppet state of Manchukuo to oversee the newly acquired region. The League of Nations vehemently protested Japan's aggression, but Japan then withdrew from it.

Japan invades China (1937)

Scene from the battle of Wuhan

The 1920s saw a weak and politically chaotic China. Warlords of the many provinces of China constantly feuded, and the central government was weak and decentralized, unable to do anything to stop conflict. In 1927 Chiang Kai-Shek gained control of the Kuomintang (the Chinese government) and its National Revolution Army. Chiang led an expedition to defeat southern and central Chinese warlords and gain the allegiance of northern warlords. He was successful, and he soon focused on what he perceived to be a greater threat than Japan, which was communism. But in 1937, the deposed warlord general of Manchuria kidnapped Chiang and refused to release him until he at least temporarily united with the communists against the Japanese threat. The Japanese army responded by staging the Battle of Lugou Bridge, which was supposed to provoke open war between China and Japan. It worked and the Sino-Japanese War began. The beginning of the conflict was marked by the Chinese strategy of giving up land in order to stall the Japanese. It is important to note that the Japanese was not to completely take over China; rather, the Japanese wanted to set up puppet governments in key regions that would protect and advance Japanese interests. The fall of Nanjing in the early stages of this conflict saw the beginning of Japanese war atrocities. 100,000-300,000 were killed in the six weeks after Nanjing was captured. Other war crimes committed included widespread rape, arson, and looting.

Anti-Comintern Pact and Tripartite Pact

These were pacts between Germany, Italy, and Japan. The Anti-Comintern pact had been a pact that denounced communism and it was initially signed by Japan and Germany. However, later, as German and Italian relations improved, Italy also signed and this was made stronger later by the Rome-Berlin-Tokyo Axis in 1938. The Tripartite Pact also strengthened the alliance and it was basically a confirmation of the Rome-Berlin-Toyko Axis.

Pearl Harbor and Simultaneous Invasions (early December 1941)

Pearl Harbor during the attack

On December 7, 1941, Japanese warplanes commanded by Vice Admiral Chuichi Nagumo carried out a surprise air raid on Pearl Harbor, Hawaii, the largest U.S. naval base in the Pacific. The Japanese forces met little resistance and devastated the harbor. This attack resulted in 8 battleships either sunk or damaged, 3 light cruisers and 3 destroyers sunk as well as damage to some auxiliaries and 343 aircraft either damaged or destroyed. 2408 Americans were killed including 68 civilians; 1178 were wounded. Japan lost only 29 aircraft and their crews and five midget submarines. However, the attack failed to strike targets that could have been crippling losses to the US Pacific Fleet such as the aircraft carriers which were out at sea at the time of the attack or the base's ship fuel storage and repair facilities. The survival of these assets have led many to consider this attack a catastrophic long term strategic blunder for Japan.

The following day, the United States declared war on Japan. Simultaneously to the attack on Pearl Harbor, Japan also attacked U.S. air bases in the Philippines. Immediately following these attacks, Japan invaded the Philippines and also the British Colonies of Hong Kong, Malaya, Borneo and Burma with the intention of seizing the oilfields of the Dutch East Indies.

Following the Japanese attack on Pearl Harbor, Germany declared war on the United States on December 11, 1941, even though it was not obliged to do so under the Tripartite Pact of 1940. Hitler made the declaration in the hopes that Japan would support him by attacking the Soviet Union. Japan did not oblige him, and this diplomatic move proved a catastrophic blunder which gave President Franklin D. Roosevelt the pretext needed for the United States joining the fight in Europe with full commitment and with no meaningful opposition from Congress. Some historians mark this moment as another major turning point of the war with Hitler provoking a grand alliance of powerful nations, most prominently the UK, the USA and the USSR, who could wage powerful offensives on both East and West simultaneously.

Allied Defeats in the Pacific and Asia (late December 1941-1942)

Simultaneous with the dawn raid on Pearl Harbor, the Japanese carried out an invasion of Malaya, landing troops at Kota Bharu on the east coast, supported by land based aircraft from bases in Vietnam and Taiwan. The British attempted to oppose the landings by dispatching Force Z, comprising the battleship HMS Prince of Wales and the battlecruiser HMS Repulse, with their escorting destroyers, from the naval base in Singapore, but this force was intercepted and destroyed by bombers before even reaching their objective.

In a series of swift maneuvers down the Malay peninsula, thought by the British to be "impassable" to an invading force landing so far north, the Japanese advanced down to the Johor Straits at the southernmost tip of the peninsula by January 1942. The Japanese were even using tanks, which the British had incorrectly thought would not be able to penetrate the jungles.

During a short two week campaign the Japanese crossed the Straits of Johor by amphibious assault and conducted a series of sharp battles, notably the battle of Kent Ridge when the Royal Malay Regiment put up a brave but futile effort to stem the tide. Singapore fell on February 15, 1942 and with its fall, Japan was now able to control the sea approaches from the Indian Ocean through the Malacca Straits. The natural resources of the Malay peninsula, in particular rubber plantations and tin mines, were now in the hands of the Japanese.

Other Allied possessions, especially in the oil rich East Indies (Indonesia) were also swiftly captured, and all organised resistance effectively ceased, with attention now shifting to events closer to Midway, the Solomon Islands, the Bismark Sea and New Guinea.

Allies Regroup and the Battle of Midway (1942)

Following the attack on Pearl Harbour, the US military sought to strike back at Japan, and a plan was formulated to bomb Tokyo. As Tokyo could not be reached by land based bombers, it was decided to use an aircraft carrier to launch the attack close to Japanese waters. The Doolittle Raid was carried out by James H. (Jimmy) Doolittle and his squadron of B-25 medium bombers, launched from the USS Hornet. The raid achieved little strategically, but was a tremendous morale booster in the dark days of 1942. It also led to the decision by the Japanese military to attack the only logical base of the attackers, the tiny atoll of Midway.

A powerful force of warships, with four large fleet carriers at its core (Akagi, Kaga, Hiryu and Soryu) attacked Midway. The US navy, with the aid of intercepted and decoded Japanese signals, were ready and launched a counter attack with the carriers USS Enterprise and USS Yorktown, destroying all four of the Japanese fleet carriers. This was a devastating blow to the Japanese and is considered the turning point of the Pacific War. The Japanese had largely roamed the Pacific Ocean, the South China Sea, the Malacca Straits and the Indian Ocean with impunity, launching raids from these same four carriers on Allied bases in these areas including Darwin, Colombo and along the Indian east coast. With the loss of these carriers and more importantly their cadre of irreplaceable hard core highly trained naval aviators, the Japanese could no longer maintain an effective offensive and became largely defensive from then on.

Island Hopping (1943- Late 1944)

Island hopping was a campaign of capturing key islands in the Pacific that were used as prerequisites, or stepping stones, to the next island with the eventual destination being Japan, rather than trying to capture every island under Japanese control. Allied forces often assaulted weaker islands first, while starving out the Japanese strongholds before attacking them.

The Atomic Bomb (August 1945)

Detonation of the first atomic bomb test - Trinity.

On August 6, 1945, a lone B-29 bomber, named the Enola Gay, appeared over the skies of Hiroshima. Air raid sirens went off around the city and people ran for their shelters. However, minutes later, the all-clear symbol was given. Although it had been a seemingly harmless run, the B-29 had, in fact, dropped a single bomb (this bomb was called "Little Boy"). This bomb detonated about 1,900 feet over Hiroshima and leveled much of the city within a few thousandths of a second. Tens of thousands were killed immediately and many more would eventually die from the radiation poisoning.

However, Japan did not surrender to the United States, so three days later, on August 9, 1945, a B-29 named Boxcar dropped an atom bomb on the city of Nagasaki (this bomb was called "Fat Man"). Although the bomb was actually more powerful than the Hiroshima bomb, the foggy weather conditions and the hilly terrain of Nagasaki somewhat shielded a portion of the city from the worst effects.

This, in conjunction with other factors affecting the state of the war, led to a ceasefire with Japan, and surrender a month later.

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