The American public reacted with outrage to the Japanese attack on Pearl Harbor. This reaction was exemplified by the actions of the government. Pres. Roosevelt called Dec. 7, 1941 a "date which will live in infamy" and Congress voted to go to war with only one dissenting vote.
The attack on Pearl Harbor settled the question of whether the US should go to war. The public had been divided over the question but the attack unified public opinion. Men flocked to recruting offices to join the military. The nation was completely ready to go to war.
There was a darker side to this as well. The reaction included strong anti-Japanese feeling that ended up being directed against Japanese-Americans. It was this aspect of the reaction that led to the internment of Americans of Japanese descent.
Overall, then, the American public was completely outraged by the attack and was eager to go to war.