Japan took control over Manchuria in China which had natural resources that Japan needed. They used the Mukden incident as an excuse for taking the region. Once Japan took the region they renamed it to Manchukuo.
The Battle of Niihau
Since Japan dropped out of the League of Nations and were invading China, countries stopped trading with Japan. This caused Japan to be in an even worse situation.
"A Date in Which We Live in Infamy"
Japan needed to attack Southwest Asia for resources. But doing so would start war with America. Japan planed an attack on Pearl Harbor in Hawaii. Japan Believed that this would be the only threat in the pacific. The Japanese planed for the attack to be a complete surprise. Overall the attack was unsuccessful, because they failed to destroy oil storages and aircraft carriers.
U.S. Joins the War
A Japanese plane crash landed on one of the islands during the attack on Pearl Harbor. The pilot convinced natives he was friendly and then began to go on a rampage. The pilot was then killed ending the battle.
In a speech given by Franklin D. Roosevelt, he staits that December 7th 1941, was a date that the U.S. lives in infamy. This was because of the attack on Pearl Harbor. The attack along with the speech inspired many Americans to enlist in the U.S. Military.
Because of the Attack on Pearl Harbor, The U.S. declared war on Japan and Germany declared war an the U.S. The U.S. sent troops to Europe to push Germany back into the Rhineland