Pearl Harbor Attack
On the morning of 7 December 1941, carrier-based aircraft of the Imperial Japanese Navy struck the US Pacific Fleet at its base at Pearl Harbor, on the Hawaiian island of Oahu. The raid killed more than 2,400 Americans and crippled much of the fleet's battleship force. It ended the debate in the United States over whether to join the war, and it turned a conflict in Europe and China into a truly global one.
The roots of the attack lay in Japan's war in China, which had expanded sharply in 1937, and in its ambitions to dominate Southeast Asia. As Japan advanced, the United States responded with economic pressure. After Japanese forces occupied southern French Indochina in 1941, Washington, joined by Britain and the Dutch government in exile, froze Japanese assets and cut off oil exports. Since Japan relied heavily on imported oil, its leaders saw a choice between retreating from their conquests and seizing the resources of Southeast Asia by force. Negotiations in the autumn of 1941 failed to resolve the deadlock. Japanese planners concluded that the US Pacific Fleet could threaten their southern advance and decided to neutralize it with a surprise blow.
A task force of six aircraft carriers crossed the North Pacific under radio silence and launched two waves of aircraft from north of Oahu. The attackers hit battleships moored along Ford Island, as well as airfields and other installations. The USS Arizona exploded after a bomb struck its magazine, and the Oklahoma capsized. In all, eight battleships were damaged or sunk, though most were eventually raised and returned to service, with the exceptions of the Arizona and Oklahoma, which were not restored to service. The American aircraft carriers were away at sea and escaped, as did the base's fuel tanks and repair facilities, which the Japanese left largely untouched. These omissions proved significant.
The day after the attack, President Franklin Roosevelt addressed Congress, calling 7 December "a date which will live in infamy," and Congress declared war on Japan with almost no opposition. Germany and Italy then declared war on the United States a few days later, bringing America fully into the European conflict. Japan simultaneously attacked British, Dutch, and American possessions across Southeast Asia and the Pacific.
Pearl Harbor became a lasting national symbol, and the sunken Arizona is now a memorial. The attack also prompted long arguments about whether American leaders had missed warning signs. Investigations and historians have generally found intelligence failures and poor communication rather than deliberate foreknowledge, though conspiracy theories persist. Strategically, the raid brought Japan a short-term advantage but awakened the industrial power of a country that would ultimately help defeat it.