Military History/Japan enter WWII


Why did Japan enter WWII?


In a word a quest for Power.  To understand Japan you have to understand its history dating back to the Mongol invasions in 1274 and 1281.  The Mongols then controlling China attempted to invade Japan twice and both times vast storms wrecked the invasion fleets that had been built in Korea and in China. For centuries Korea and Japan fought vast naval battles in the waters around both countries.  Japan in 1543 came in contact with the west in the form of Portuguese traders who visited the Island nation.  For a time trade was welcome but eventually the Japanese believed that the west was a a threat and threw out the westerners.  Japan was an isolated country until the US came calling.  In 1853 Commodore Perry of the US navy visited Japan and in some ways demanded Japan open up to trade.  Japan quickly westernized much of it country with the Japanese Army following the example of the German Army and the British Navy became the teacher of the Japanese Navy.  Japan quickly built up a modern navy and in 1894 went to war with China over control of Korea.  The Japan won but Russia stepped in and took over Korea.  The Japaneses spent years building up their new navy and in 1904 Japanese army and naval forces engaged the Russians.  With the defeat of the Russian Baltic fleet at Battle of Tsushima in 1905 Japan and Russia negotiated a settlement and Japan took over Korea.  Japanese alliance with Great Britain in World War 1 allowed japan to take several islands that Germany had in the the Pacific.  The Japanese gained a taste of conquest and saw a Japanese run Asia.  The Japanese Army began destabilize the civilian government in the 1920s and by the early 1930s the Japanese Army ran Japan similar to a Fascist state.  In 1931 the Japanese Army on its own invaded Manchuria and took the region from China.  In 1937  China and Japan went to war with Japan invading and taking several coastal cities.  In 1939 the Japanese ran into a a problem with the USSR.  The Japaneses in 1939 fought and lost a series of battles with the Soviet Union for control of eastern Siberia.  The Japanese army feared the Soviets after their defeat and vowed to never fight the Soviets again.  The China war raged on and so in the US there was frustration with Japan and its treatment of the Chinese.  First scrap metal was denied to the Japanese and then in summer 1941 the US stopped oil sales to Japan.  The US told the Japanese to give up in China or no oil.  This was the final straw and the Army run Japanese government ordered the navy to attack the US.  

Japanese quest for control of China and dominance of the Pacific forced the the US to turn off the oil thus Japan felt they had to take on the US Navy in order to take the oil supplies in the Dutch East Indies.

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Paul Sutton


I can answer questions on World War Two weapons, tactics, and strategy. I can answer questions on Weapons systems and their development. I can answer guestions on Space exploration history. I am a World War 2 expert. I study Military Weapons Systems and the usage of those systems.


I work for Saint Petersburg College as a TRS or Technology resources specialist. I read 10 to 15 books a year on World War 2 and weapon systems. I also have a BA in History from USF.

I have a BA in history from USF.

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