On December 7th, 1941, the United States officially declared war to Japan, after an overwhelming attack by the Japanese Imperial Navy on the US Pacific Fleet deployed in Pearl Harbor, in the island of Oahu, Hawaii. The raid started at 7:53 a.m. on that dire Sunday. Japanese planes attacked in two turns. A total of 353 planes arrived in Oahu. The first group was led by Mitsuo Fuchida.

The military operation devastated 13 US warships and 188 aircrafts, in addition to 2,403 troops and 68 civilians dead. However, three aircraft carriers of the US Pacific Fleet were not moored at harbor and were not attacked. Therefore, the US Pacific Command took less time than Japanese expected to recover -from six months to one year.

Admiral Isoroku Yamamoto planned the operation within the framework of World War II, particularly the beginning of the Pacific Campaign. But the offensive was not limited to the air. Japan also used five Kohyoteki mini-submarines that shelled on the US vessels after the air bombing. All of these submarines were neutralized. However, one of them sank cruiser Ward. Nine out of the 10 crew members of the five submarines died. The only survivor, Kazuo Samaki, was captured and became the first US prisoner in World War II.

Noteworthy, Japan had been under a metal and oil embargo since 1938 and the air-naval offensive was aimed at finishing this move that ran against the Japanese economic interests in that part of the world.

The attack led by Vice-Admiral Chuichi Nagumo, intended to neutralize the enemy fleet for a long time. The fundamental mission was to occupy the West colonies in Southeast Asia, such as the Philippines, Malaysia and Thailand, in order to break with the embargo.

The Japanese empire estimated that a militarily weaken United States would seek peace talks in favorable conditions. The Japanese High Command was not interested in a protracted war. However, while the stunning attack on Pearl Harbor was quite a success, it just woke up the fierce US tiger that eventually liquidated its assailants by using the unprecedented nuclear power against the cities of Hiroshima and Nagasaki.

In the United States, a strong movement took issue with the country's involvement in the war. However, after the attack, President Franklin Delano Roosevelt declared war to Japan. Four days later, Hitler declared war to the United States.