Things I know about WWII

America, the Soviet Union, France, and Britain were good

Japan, Italy, and Germany were bad (why is Germany always bad?)

America got involved after Pearl Harbor was bombed by the Japanese

America dropped atomic bombs on Hiroshima and Nagasaki

The war went from the late 30s to the early 40s

Millions of people were killed in German concentration camps during WWII

Why did the Germans get themselves into ANOTHER war?

What was this war about?