"... For the next five months, until the
Battle of the Coral Sea in early May, Japan's far-reaching offensives proceeded untroubled by fruitful opposition. American and Allied morale suffered accordingly. Under normal political circumstances, an accomodation might have been considered. However, the memory of the "sneak attack" on Pearl Harbor fueled a determination to fight on. Once the
Battle of Midway in early June 1942 had eliminated much of Japan's striking power, that same memory stoked a relentless war to reverse her conquests and remove her, and her German and Italian allies, as future threats to World peace."
http://www.history.navy.mil/photos/events/wwii-pac/pearlhbr/pearlhbr.htm
It's what inspired my father to enlist. When returning home from work one afternoon before he was to report to Great Lakes he was greeted with a draft notice. If he had not chosen to enlist when he did he would have been drafted into the Army as opposed to being in the Navy for the duration plus six months of the war.