Top Photo: The USS Arizona burns after the Pearl Harbor attack. Courtesy of the National Archives and Records Administration

The surprise Japanese attack on Pearl Harbor on December 7, 1941, led to the entry of the United States in World War II.

Just before 8:00 a.m. local time that Sunday morning, planes launched from Imperial Japanese Navy aircraft carriers attacked the US Pacific Fleet, killing more than 2,400 Americans and severely damaging naval and air forces in the US territory of Hawaii. The following day, President Franklin D. Roosevelt addressed Congress, describing December 7 as “a date which will live in infamy,” and asked for an official declaration of war against the Japanese Empire. 

The attack followed years of escalating tensions between the United States and Japan over Japanese expansion in East Asia and the Pacific. Japan’s full-scale war against China, which began in 1937, and its subsequent occupation of French Indochina intensified American opposition. In July 1941, the Roosevelt administration froze Japanese assets and imposed restrictions that effectively cut off Japan’s access to American oil and steel. Japanese leaders chose to pursue war rather than abandon their expansionist objectives, planning attacks against Dutch, British, and American possessions across the Pacific and Southeast Asia.

Admiral Isoroku Yamamoto, commander-in-chief of Japan’s Combined Fleet, developed the plan to attack Pearl Harbor. He sought to cripple American naval power early in the conflict, giving Japan time to secure strategic resources and consolidate its territorial gains. The operation centered on the Kidō Butai, Japan’s carrier striking force, commanded by Vice Admiral Chūichi Nagumo. On November 26, 1941, the force departed northern Japan with six aircraft carriers: Akagi, Kaga, Sōryū, Hiryū, Shōkaku, and Zuikaku. Sailing across the North Pacific under strict radio silence, the force approached Hawaii undetected. In Washington, D.C., negotiations between the United States and Imperial Japan had broken down, but Japanese diplomats had not yet formally severed relations with America. 

On the morning of December 7, the six carriers launched two waves of aircraft against US military installations on Oahu. The first wave struck at approximately 7:55 a.m., followed by a second wave beginning around 8:45 a.m. Japanese aircraft attacked battleships anchored in Pearl Harbor and targeted American aircraft on the ground to prevent a counterattack. Eight battleships were damaged, with several sinking or being forced aground, and 188 American aircraft were destroyed. The attack also killed military personnel and civilians across the island.

Despite the destruction, Japan failed to eliminate American naval power in the Pacific. None of the US Navy’s three Pacific Fleet aircraft carriers were at Pearl Harbor during the attack. The Japanese also left the base’s major fuel storage facilities, repair yards, and submarine facilities intact. These resources helped sustain subsequent American naval operations. Most of the damaged American battleships were eventually salvaged, repaired, and returned to service.

On December 8, Congress declared war on Japan. Germany and Italy declared war on the United States on December 11, prompting American declarations of war against both countries. The attack transformed American participation in World War II, bringing the United States into direct conflict with the Axis powers in both the Pacific and Europe.