The bombing of Pearl Harbor was the immediate cause that made America join WWII.
Some majority battles include Battle of Stalingrad, and the battle that lead to D-Day— I don’t know these off the top of my head, I apologize.
War affected American economy as it boosted it and helped them out of the Great Depression for a spur of a need of war products. Society allowed women to work in jobs due to the lack of men being available. As for culture... I’m not quite sure...
Hope this helps!
