Japan was a smart, expanding and a large country. These points though helped in the loss of the war. Japan lost World War 2 through different aspects from before the war and during the war. The errors made played vital rolls in the war and as the errors tallied up the war headed USA's way.
Before the war, Japan had already made wrong assumptions. The first wrong assumption made by the Japanese was that Germany would win the war in Europe so that the US and Britain could not turn their entire strength against Japan which would mean Japan had a stronger force and could chose whether to invade or not invade US and Britain. Secondly, US lacked fighting spirit and they thought that the bombing of Pearl Harbor would leave US demoralized and ask for compromised peace. This did not lose their fighting spirit but made them even more encouraged to win, "Yesterday, December 7, 1941- date which will live in infamy" said by President Roosevelt. Lastly Japan thought that the bombing of Pearl Harbor would cause the US to have barely any ships and therefore would take a long time to rebuild. Japan failed to sink 3 aircraft carriers at sea and these carriers was used to good effect at the battle of Midway. Much of the shipping destroyed in Pearl Harbor was inferior and obsolete. They had underestimated US's industrial power which led therefore to war.
During the war Japan had many wrong doings. Firstly the Army and navy caused Japan's war effort to weaken. Little Coordination was given in military strength and operations and the navy and army wanted to do different things such as attack and defend. In battles either one of the forces did not support each other.
Japan's military leaders were reluctant to revise their war strategy to deal with new allied tactical methods. They relied too much on the fighting spirit of the Japanese forces and didn't look great enough into tactics. The effects of relying on the fi...