It was an event that changed the course of American history and the lives of millions.When the Japanese invaded Pearl Harbor the morning of Dec. 7, 1941, it thrust the United States into the middle of World War II. Congress declared war on Japan the next day.The attack on Pearl Harbor, which took place 71 years ago today, was a surprise strike. The death toll was considerable as 2,402 Americans were killed and 1,282 were wounded. All eight U.S. Navy battleships in the harbor were damaged – with four sunk.The American people were as shocked about the attack as the American military.