How did the attack on Pearl Harbor change the course of World War II?

Before pearl harbor the allies were losing the war to the axis powers. after the pearl harbor the united states got involved and this changed the coarse of the war because the unitecd states had a alot of resources and supplies that the allies needed so badly. s

It was a surprise attack on America that led to the US joining World War II ... The Pearl Harbor attack plan was conceived by Admiral Isoroku Yamamoto, ... The Japanese simply did not practice combined arms doctrine, which utilizes different ... of practice in changing from cruise to attack formation, up to 1,800 meters (30 ... t his bombing forced Americans to go to war when previously they did not want involvement It changed the course of WW2 because it fored the American.