In the 1930s, differences over China led to mounting tensions between the United States and Japan. In 1931, Japan conquered Manchuria, and later took over Indochina-- the country's expansionist policies concerned the US, as they had economic interests in East Asia, and in response, the US discontinued exports of oil and raw materials to Japan. On the morning of December 7, 1941, Japan carried out an attack on Pearl Harbor that resulted in the deaths of more than 2,400 Americans. The country used 353 fighter planes, bombers, and torpedoes in the two waves of attacks, which occurred about 45 minutes apart. The assault came as a shock to America, and the country replaced their neutral stance on the war with a fury that triggered the US' official entry into World War II. The picture above shows an aerial view of battleships of the US Pacific Fleet after 360 Japanese warplanes attacked. Click through our gallery to check out some of the most iconic photos of the attack on Pearl Harbor.