Why did the Japanese lose World War 2?
They got nuked. And the Emperor was virtually a hostage in his
own palace. Japan's chances of winning against the U.S. were very
remote indeed. Probably Japan was hoping to shift the balance of
power in the Pacific region away from America and to strenghten its
own position. Alternatively, the whole venture may have been
irrational from the outset.
Allied submarines had cut the mainland of Japan from receiving raw materials (rubber, oil, metals). Pilots of the Japenese air arms (Navy & Army) fought until they were killed, no relief. Fresh pilots joining them had as few as 30 hours flying thus were not fully qualified. The Japenese airplanes had not changed much since the start of the war. Allied aircraft were faster had better armor and better trained pilots. American industries took about a year to retool and start producing war goods. America was a huge industrial nation with plenty of natural raw materials. When ask of his thoughts of the success of the Pearl Harbor Raid, Admiral Isoroku Yamamato said, "I fear we have only awoken a sleeping giant." He was speaking of the American Industry.
They simply picked the wrong fight. Japan did not have the people or resources to wage a long term war against the United States. Japan was planning for a short was with the U.S.
Even some in the Japanese command believed a war with the United States could not be done.
The popular story is that the commander of the attack on Pearl
Harbor, Admiral Yamamoto said "I fear all we have done is to
awaken a sleeping giant and fill him with a terrible resolve."
indicating that he did not believe Japan could .
1) Two American atomic bombs made them decide to surrender unconditionally.
2) They were overconfident by hoping to destroy the American Pacific fleet in a single surprise attack.
3) They had invaded China as far back as 1933, planning on enslaving the Chinese people [ then China was a vast land of one million villages ] for manpower, agricultural products and natural resources for Japan.
4) Their spirit made that their own season army (especially navy pilot) who involve in kamikaze and banzai charge lost and left out the less experience army by the end of the war.
When American military might was finally in full swing, successfully defeating Japanese occupiers of many lands, the Japanese had lost their most experienced sailors and airmen. In desperation, poorly trained replacements added to her manpower losses in battle every day.