On a calm Sunday morning of December 7, 1941, the United States was thrust into the second world war, a conflict that had been raging across Europe and Asia. The peaceful morning was shattered when Japan launched an unexpected attack on the Pearl Harbor naval base in Hawaii. This attack pushed America, which had been staying out of the war, straight into the fray. America's entry into the war dramatically shifted the balance. The country's industrial might was used to produce weapons and vehicles for the war effort. American soldiers fought bravely in battles across the globe, from the sandy beaches of Normandy in Europe to the tropical islands of the Pacific. The war ended in 1945 when the United States dropped atomic bombs on two Japanese cities, Hiroshima and Nagasaki. These events marked the first and only use of nuclear weapons in war. World War II was a time of great change and challenges, leaving a lasting impact on the world and America.