Pearl Harbor attack, (December 7, 1941), surprise aerial attack on the U.S. naval base at Pearl Harbor on Oahu Island, Hawaii, by the Japanese that precipitated the entry of the United States into World War II. The strike climaxed a decade of worsening relations between the United States and Japan.
Pacific War: Japanese-controlled areas of China
The Japanese seized Manchuria in 1931 and occupied much of the coast and North China Plain by 1941.(more)
In the late 1930s, American foreign policy in the Pacific hinged on support for China, and aggression against China by Japan therefore necessarily would bring Japan into conflict with the United States. As early as 1931 the Tokyo government had extended its control over the Chinese province of Manchuria, and the following year the Japanese cemented their hold on the region with the creation of the puppet state of Manchukuo. A clash at the Marco Polo Bridge near Beijing on July 7, 1937, signaled the beginning of open warfare between Japan and the United Front of Chinese Nationalists and the Chinese Communist Party. In response, the United States government extended its first loan to China in 1938.
In July 1939 the U.S. announced the termination of the 1911 Treaty of Commerce and Navigation with Japan. Beginning in the summer of 1940, the U.S. began to restrict the export to Japan of materials useful in war. Between June 1940 and the fateful crisis of December 1941, the tension constantly mounted. In July 1941, by which time the Japanese had occupied all of Indochina and had entered into an alliance with the Axis powers (Germany and Italy), the U.S. government severed all commercial and financial relations with Japan. Japanese assets were frozen, and an embargo was declared on shipments to Japan of petroleum and other vital war materials. Militarists were steadily gaining in influence in the Tokyo government; they bitterly resented U.S. aid to China, which by this time had been stepped up. They saw in the German invasion of the Soviet Union an unrivaled opportunity to pursue a policy of aggression in the Far East without danger of an attack upon their rear by the forces of the Red Army. Nonetheless, negotiations looking to find some kind of understanding between the United States and Japan took place through the autumn of 1941, and not until near the end of November did it become clear that no agreement was possible.
Yamamoto Isoroku, commander in chief of Japan’s Combined Fleet during World War II.(more)
Although Japan continued to negotiate with the United States up to the day of the Pearl Harbor attack, the government of Prime Minister Tōjō Hideki decided on war. Adm. Yamamoto Isoroku, the commander in chief of Japan’s Combined Fleet, had planned the attack against the U.S. Pacific Fleet with great care. Once the U.S. fleet was out of action, the way for the unhindered Japanese conquest of all of Southeast Asia and the Indonesian archipelago would be open. The order for the assault was issued on November 5, 1941, and on November 16 the task force began its rendezvous in the Kuril Islands. Commanders were instructed that the fleet might be recalled, however, in case of a favourable outcome of the negotiations in Washington, D.C. On November 26, Vice Adm. Nagumo Chuichi led a fleet including 6 aircraft carriers, 2 battleships, 3 cruisers, and 11 destroyers to a point some 275 miles (440 km) north of Hawaii. From there about 360 planes in total were launched.
Warnings and responses
Kimmel, Husband; Pearl Harbor attack
Adm. Husband Edward Kimmel.
The U.S. Pacific Fleet had been stationed at Pearl Harbor since April 1940. In addition to nearly 100 naval vessels, including 8 battleships, there were substantial military and air forces. As the tension mounted, Adm. Husband E. Kimmel and Lieut. Gen. Walter C. Short, who shared command at Pearl Harbor, were warned of the possibility of war, specifically on October 16 and again on November 24 and 27. The notice of November 27, to Kimmel, began, “This dispatch is to be considered a war warning,” went on to say that “negotiations have ceased,” and directed the admiral to “execute an appropriate defensive deployment.” Kimmel also was ordered to “undertake such reconnaissance and other measures as you deem necessary.” The communication of the same day to Short declared that “hostile action is possible at any moment” and, like its naval counterpart, urged “measures of reconnaissance.”
Examine the facts and timeline of the attack on Pearl Harbor on December 7, 1941
The U.S. naval base at Pearl Harbor on Oahu Island, Hawaii, was attacked by the Japanese on December 7, 1941.(more)
In response to these warnings, the measures taken by the army and navy commanders were, as the event proved, far from adequate. Short ordered an alert against sabotage and concentrated most of his fighter planes at the base on Wheeler Field in an effort to prevent damage to them. He also gave orders to operate five of the mobile radar sets that had been set up in the island from 4:00 AM to 7:00 AM, considered to be the most dangerous period. (Radar training, however, was in a far-from-advanced stage.)
Kimmel, despite the fact that his intelligence had not been able to locate substantial elements in the Japanese fleet—especially the first-line ships in carrier divisions 1 and 2—did not expand his reconnaissance activities to the northwest, the logical point for an attack. He moored the entire fleet (save that part which was at sea) in the harbour and permitted a part of his personnel to go on shore leave. Neither of these officers suspected that the base at Pearl Harbor would itself be subjected to attack. Nor, for that matter, is there any indication that their superiors in Washington were in any way conscious of the approaching danger. In the 10 days between the war warning of November 27 and the Japanese attack itself, no additional action was taken by Washington.
WWII: JAPANESE AMERICAN INTERNMENT IN PICTURES
Early on Sunday morning, December 7, Washington learned that the Japanese ambassadors had been instructed to ask for an interview with the secretary of state at 1:00 PM (7:30 AM Pearl Harbor time). This was a clear indication that war was at hand. The message took some time to decode, and it was not in the hands of the chief of naval operations until about 10:30. It was delivered to the War Department between 9:00 and 10:00 AM. Gen. George C. Marshall, the U.S. Army chief of staff, was out horseback riding and did not see the dispatch until he arrived at his office about 11:15 AM. The chief of naval operations, Adm. Harold Stark, even then did not think that the communication called for any additional instructions to Kimmel. However, Marshall did decide to send a new warning and gave orders to the military command to communicate with the navy. He did not telephone, fearing that his words might be intercepted, and instead sent his dispatch by telegram. There was a mix-up in communication, however, and the warning did not reach Hawaii until after the attack had begun. It is important to note that it had not been filed until noon, only an hour before the Japanese planes moved in on the base.
At Pearl Harbor itself, there were incidents that, properly interpreted, might have given a brief warning. Four hours before the decisive moment, a Japanese submarine was sighted by the minesweeper USS Condor. About two and a half hours later, the commander of the destroyer USS Ward sent a message saying that he “had attacked, fired upon, and dropped depth charges upon submarine operating in defensive sea area” near Pearl Harbor. While Kimmel waited for confirmation of this report, the Japanese opened hostilities. In these same morning hours, U.S. Army Pvt. George Elliott, practicing on the radar set after its normal closing time, noticed a large flight of planes on the screen. When he telephoned his lieutenant, he was told to disregard the observation, as a flight of B-17 bombers from the United States was expected at that time. Once again an opportunity was missed.
The attack
Learn why Japan attacked Pearl Harbor causing the United States to join Allied forces in World War II
A detailed video timeline of the Pearl Harbor attack, December 7, 1941.(more)
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Ford Island in Pearl Harbor, Hawaii, as seen from a Japanese aircraft during the attack on the U.S. Pacific Fleet, December 7, 1941.(more)
Explosions rocking the U.S. naval base at Pearl Harbor, Hawaii, during the Japanese surprise air attack on December 7, 1941.(more)
The first Japanese dive-bomber appeared over Pearl Harbor at 7:55 AM (local time). It was part of a first wave of nearly 200 aircraft, including torpedo planes, bombers, and fighters. Within a quarter of an hour the various airfields at the base were subjected to savage attack. Due to Short’s anti-sabotage measures, the U.S. military aircraft were packed tightly together at the Naval Air Station on Ford Island and adjoining Wheeler and Hickam fields, and many were destroyed on the ground by Japanese strafing. At Wheeler Field in particular the destruction was fearful. Of the 126 planes on the ground, 42 were totally destroyed, 41 were damaged, and only 43 were left fit for service. Only 6 U.S. planes got into the air to repel the attackers of this first assault. In total, more than 180 aircraft were destroyed.
Watch Japanese dive-bombers attack the U.S. naval base at Pearl Harbor to spark the Pacific War
On December 7, 1941, Japanese airplanes strike the U.S. naval base at Pearl Harbor, bringing the United States into World War II. From “The Second World War: Triumph of the Axis” (1963), a documentary by Encyclopædia Britannica Educational Corporation.(more)
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View footage of the Japanese attack on Pearl Harbor, the strike that provoked the U.S. into entering World War II
Learn about the Japanese attack on the U.S. naval base at Pearl Harbor, Oahu, Hawaii, by watching historical footage and viewing the USS Arizona National Memorial there.(more)
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At the same time a massive action was directed against Kimmel’s fleet. The ships anchored in the harbour made perfect targets for the Japanese bombers, and, because it was Sunday morning (a time chosen by the Japanese for maximum surprise), they were not fully manned. Most of the damage to the battleships was inflicted in the first 30 minutes of the assault. The battleship USS Arizona blew up with a tremendous explosion. Riddled with bombs and torpedoes, the USS West Virginia settled on an even keel on the bottom of the harbour. The USS Oklahoma, hit by four torpedoes within five minutes, rolled completely over, with its bottom and propeller rising above the waters of the harbour. The USS California, the flagship of the Pacific Battle Force, was torpedoed and ordered abandoned as it slowly sank in shallow water. The target ship USS Utah also was sunk. Hardly a vessel escaped damage. The antiaircraft crews on the various vessels were fairly prompt in getting into action, and army personnel fired with what they had, but the force of the attack was in no serious way blunted.
The battleship USS Pennsylvania in dry dock with the heavily damaged destroyers USS Cassin (left) and USS Downes after the Pearl Harbor attack, December 7, 1941.(more)
American sailors at Ford Island Naval Air Station reacting to the explosion of the USS Shaw during the second wave of attacks on the U.S. naval base at Pearl Harbor, December 7, 1941.(more)
At 8:50 AM the second wave of the attack began. Less successful than the first, it nonetheless inflicted heavy damage. The battleship USS Nevada had sustained a torpedo hit during the first wave, but its position at the end of Battleship Row allowed it greater freedom of action than the other moored capital ships. It was attempting to get underway when the second wave hit. It was struck by seven or eight bombs and was grounded at the head of the channel. The battleship USS Pennsylvania was set ablaze by bombs, and the two destroyers moored near it were reduced to wrecks. The destroyer USS Shaw was split in two by a great explosion. Shortly after 9:00 AM the Japanese withdrew.
No one could doubt that the Japanese had gained a great success. The Arizona and the Oklahoma were destroyed with great loss of life, and six other battleships suffered varying degrees of damage. Three cruisers, three destroyers, and other vessels were also damaged. U.S. military casualties totaled more than 3,400, including more than 2,300 killed. Heavy damage was inflicted on both army and navy aircraft on the ground. The Japanese lost from 29 to 60 planes, five midget submarines, perhaps one or two fleet submarines, and fewer than 100 men. The Japanese task force retired from the theatre of battle without being attacked.
Christian Writer 
