On 7 December 1941, a Japanese naval attack force launched a surprise air attack on U.S. military installations on the island of Oahu, in the U.S. Territory of Hawaii. Two waves of aircraft, totaling 253 aircraft in all, attacked the naval base at Pearl Harbor, the home of the U.S. Pacific Fleet, Hickam, Wheeler and Bellows Army airfields, Schofield Barracks, Kaneohe Naval Air Station, and Ewa Marine Corps Air Station. The attack was the greatest military defeat in U.S. history, and when it was over, 2,388 U.S. sailors, soldiers, and civilians were dead, while another 1,178 were wounded. The Japanese had sunk or damaged 21 ships of the U.S. Pacific Fleet, including eight front line battleships. The attack thrust the United Stated into World War II against Japan and her Axis allies, Germany and Italy.
While the Japanese achieved a temporary victory against the United States, the attack set in motion the chain of events that would ultimately lead to the defeat of Japan and the Axis nations in 1945. The seeds of the attack were planted in 1931, when Japan invaded the Chinese province of Manchuria. The invasion of Manchuria was the first step in Japanese imperial expansion, and in 1937 Japan launched a full scale war against China.
In response to the Japanese invasion of China, the United States increased military and financial aid to the Chinese and cut off exports of oil and other raw materials to Japan. This embargo was viewed by the Japanese as a direct threat to their national security and decided to seize and conquer other Asian and Pacific area territories that were rich in oil and the natural resources that Japan did not possess.
Japan knew that the United States did not condone its war with China and would not agree to its seizure of additional territory in Asia. Both the American and Japanese governments had taken strong diplomatic positions in regards to each other that would not allow "backing down" without some sort of national humiliation and embarrassment. While the two governments continued negotiations to find a peaceful solution to the diplomatic impasse, the Japanese government believed that war with the United States was inevitable and began to prepare accordingly.
Japan decided that the only way to defeat the United States was to preemptively destroy the U.S. Pacific Fleet at Pearl Harbor with a strong and decisive blow. They believed that American industrial might would tip the scales against Japan in a prolonged war, and felt that its military success was dependent on destroying the U.S. Pacific Fleet early in the war. While the United States was recovering from such an attack, the Japanese felt they would be able to pursue its military campaign throughout Asia and the Pacific, unimpeded by the United States.
The Japanese also believed that a decisive victory would demoralize and eliminate the will of the American people to engage in war with Japan. While history has shown us that the Japanese were greatly mistaken about this, it should be remembered that the American people in 1941 were deeply divided over the issue of war, with a large share of the populace holding isolationist views. While many Americans tended to sympathize with the Allied nations, the memory of World War I still lingered in the national psyche, and the American people as a whole had no desire to fight another war.
It can be argued that the Japanese attack was, in a sense, a desperate act by a desperate nation. Japan's quest for imperial expansion put it on a collision course with the United States. With either side unwilling to retreat from its positions, the Japanese believed there was no other course of action but war with the U.S. Once this was decided on, Japan concluded that the only route to victory was to destroy the U.S. Pacific Fleet in a quick and decisive attack. Through a long, winding and difficult road, Japan finally made the fateful decision that would forever link Japan with Pearl Harbor and 7 December 1941.