The Japanese attacked Pearl Harbor because the United States was the only country able to stop Japanese expansion in the Pacific. The Japanese also chose Pearl Harbor because it was the home of the American pacific fleet. American intervention was important to the war because the United States had the manpower and the massive industry. When in 1943 American industries kicked into gear and the army ranks climbed to millions, the United States became a massive force to be reckoned with. The United States decided to drop the Atomic Bomb because it was the only option that would not cause thousands of American casualties. I believe President Truman was correct to use the bombs on Japan because there was only one other option, invasion. If the US