Pearl Harbor Naval Base, Hawaii, is the hub of United States naval power in the Pacific Ocean. It covers 22,000 acres (8,900 hectares) on Oahu Island and lies west of downtown Honolulu. Most of the Navy's major commands in the Pacific have headquarters at the base. These include the Pacific Fleet and its fleet marine, service, and submarine forces; an antisubmarine warfare force; Fleet Air Hawaii; a naval shipyard; supply center; and an ammunition storage depot. It supports the operations of the Seventh Fleet.
Pearl Harbor is one of the world's largest and best-sheltered naval anchorages. It is formed by two mouths of the Pearl Stream. The harbor occupies about 10 square miles (26 square kilometers) of navigable water, and has three lochs (nearly landlocked lakes). Its name came from the pearl oysters that once grew in its waters.
In 1887, King Kalakaua of Hawaii gave the United States the right to develop a coaling station at Pearl Harbor. The United States Navy made its first attempt to deepen the channel through the reef outside the harbor in 1902. But the first dry dock was not completed until 1919.
A surprise attack on Pearl Harbor by Japanese forces on Dec. 7, 1941, forced the United States into World War II. Vice Admiral Chuichi Nagumo led a 33-ship Japanese striking force that steamed under the cover of darkness to within 200 miles (320 kilometers) north of Oahu. His carriers launched about 360 airplanes against the Pacific Fleet, under Admiral Husband E. Kimmel, and the Hawaiian ground troops under Lieutenant General Walter C. Short. The first bombs fell about 7:55 a.m. The chief targets were the eight American battleships among the 92 naval vessels anchored in the harbor. The attack killed 2,388 people at Pearl Harbor and wounded about 2,000. It destroyed or damaged 21 U.S. ships and over 300 planes. Kimmel and Short were criticized for the U.S. losses. Several investigations were held following the attack. "Remember Pearl Harbor!" became the rallying cry for the United States in World War II. See WORLD WAR II (Japan attacks).