Attack on Pearl Harbor

The attack on Pearl Harbor was a surprise military strike by the Empire of Japan on the United States Pacific Fleet at its naval base at Pearl Harbor on Oahu, Hawaii, on December 7, 1941. At the time, the U.S. was a neutral country in World War II. The air raid on Pearl Harbor, which was launched from aircraft carriers, resulted in the U.S. entering the war on the side of the Allies on the day following the attack. The Japanese military leadership referred to the attack as the Hawaii Operation and Operation AI, and as Operation Z during its planning.
The attack on Pearl Harbor was preceded by months of negotiations between the U.S. and Japan over the future of the Pacific. Japanese demands included that the U.S. end its sanctions against Japan, cease aiding China in the Second Sino-Japanese War, and allow Japan to access the resources of the Dutch East Indies. Japan sent out its naval attack group on November 26, 1941, just prior to receiving the Hull note, which stated the U.S. desire that Japan withdraw from China and French Indochina. Isoroku Yamamoto, commander of the Japanese Combined Fleet, planned the attack as a pre-emptive strike on the Pacific Fleet, based at Pearl Harbor since 1940, in order to prevent it from interfering with Japan's planned actions in Southeast Asia. Yamamoto hoped that the strike would enable Japan to make quick territorial gains and negotiate a peace. In addition to Pearl Harbor, over seven hours Japan launched coordinated attacks on the U.S.-held Philippines, Guam, and Wake Island; and on the British Empire in Malaya, Singapore, and Hong Kong.
The attack force, commanded by Chūichi Nagumo, began its attacks at 7:48 a.m. Hawaiian time (6:18 p.m. GMT) on December 7, 1941. The base was attacked by 353 fighters, level and dive bombers, and torpedo bombers in two waves launched from six aircraft carriers. Of the eight U.S. battleships present, all were damaged and four were sunk. All but Arizona were later raised, and six were returned to service during the war. The Japanese also sank or damaged three cruisers, three destroyers, an anti-aircraft training ship, and a minelayer. More than 180 U.S. aircraft were destroyed. A total of 2,403 Americans were killed and 1,178 others were wounded, while the Japanese lost a total of 29 aircraft, five midget submarines, and 130 men. The three U.S. carriers stationed at Pearl Harbor escaped damage because they were at sea at the time, and important base installations, including its oil storage and naval repair facilities, were not attacked.
Japan declared war on the U.S. and the British Empire later that day (December 8 in Tokyo), but the declarations were not delivered until the next day. On December 8, both the United Kingdom and U.S. declared war on Japan. On December 11, though they had no formal obligation to do so under the Tripartite Pact with Japan, Germany and Italy each declared war on the United States, which responded with a declaration of war against Germany and Italy. While there were historical precedents for unannounced military action by Japan, the lack of a formal warning and perception that the attack had been unprovoked led U.S. president Franklin D. Roosevelt to famously label December 7, 1941, "a date which will live in infamy". The attack was the deadliest event ever in Hawaii, and the deadliest foreign attack on the U.S. until the September 11 attacks of 2001.
War between the Empire of Japan and the United States was seen as a possibility since the 1920s. Japan had been wary of American territorial and military expansion in the Pacific and Asia since the late 1890s, followed by the annexation of islands, such as Hawaii and the Philippines, which they felt were close to or within their sphere of influence.
At the same time, Japanese strategic thinkers believed that Japan needed economic self-sufficiency in order to wage modern war. The experiences of World War I had taught the Japanese that modern wars would be protracted, require total mobilization and create vulnerabilities for trade embargoes and encirclement. As a consequence, Japan needed access to strategically important resources (e.g. iron, oil) that could not be extracted at sufficient levels in the home islands.
Although Japan had begun to take a hostile stance against the United States after the rejection of the Racial Equality Proposal, the relationship between the two countries was cordial enough that they remained trading partners. Tensions did not seriously grow until Japan's invasion of Manchuria in 1931. Over the next decade, Japan expanded into China, leading to the Second Sino-Japanese War in 1937. Japan spent considerable effort trying to isolate China and endeavored to secure enough independent resources to attain victory on the mainland. The "Southern Operation" was designed to assist these efforts. Nevertheless, Japan would still rely heavily on U.S. oil imports, including to Japanese forces in Japan-occupied Manchuria. In a memorandum dated October 24, 1934, Chief of the Division of Far Eastern Affairs Stanley K. Hornbeck discussed his meeting with Teagle to U.S. President Franklin D. Roosevelt, and how Standard Oil New Jersey head Walter C. Teagle was also uncooperative with U.S. recommendations and also given special treatment by the Japanese government, who made him and Standard Oil New Jersey less subjected to Japan's national business regulation policies than they did other companies. Hornbeck noted in the memorandum that as a result of Teagle's business dealings with Japan, "petroleum products now imported into Japan is of American origin."
Starting in December 1937, events such as the Japanese attack on USS Panay, the Allison incident, and the Nanking Massacre swung Western public opinion sharply against Japan. The United States unsuccessfully proposed a joint action with the United Kingdom to blockade Japan. In 1938, following an appeal by President Roosevelt, American companies stopped providing Japan with implements of war.
In 1940, Japan invaded French Indochina, attempting to stymie the flow of supplies reaching China. The United States halted shipments of airplanes, parts, machine tools, and aviation gasoline to Japan, which the latter perceived as an unfriendly act. The United States did not stop oil exports, however, partly because of the prevailing sentiment in Washington that given Japanese dependence on American oil, such an action was likely to be considered an extreme provocation.
In mid-1940, President Franklin D. Roosevelt moved the Pacific Fleet from San Diego to Hawaii. He also ordered a military buildup in the Philippines, taking both actions in the hope of discouraging Japanese aggression in the Far East. Because the Japanese high command was mistakenly certain any attack on the United Kingdom's Southeast Asian colonies, including Singapore, would bring the United States into the war, a devastating preventive strike appeared to be the only way to prevent American naval interference. An invasion of the Philippines was also considered necessary by Japanese war planners. The American War Plan Orange had envisioned defending the Philippines with an elite force of 40,000 men; this option was never implemented due to opposition from Douglas MacArthur, who felt he would need a force ten times that size. By 1941, American planners expected to have to abandon the Philippines at the outbreak of war. Late that year, Admiral Thomas C. Hart, commander of the United States Asiatic Fleet, was given orders to that effect.
The United States finally ceased oil exports to Japan in July 1941, following the seizure of French Indochina after the Fall of France, in part because of new American restrictions on domestic oil consumption. Because of this decision, Japan proceeded with plans to take the oil-rich Dutch East Indies. On August 17, Roosevelt warned Japan that America was prepared to take opposing steps if "neighboring countries" were attacked.
Japan and the United States engaged in negotiations during 1941, attempting to improve relations. In the course of these negotiations, Japan offered to withdraw from most of China and Indochina after making peace with the Nationalist government. It also proposed to adopt an independent interpretation of the Tripartite Pact and to refrain from trade discrimination, provided all other nations reciprocated. Washington rejected these proposals. Japanese Prime Minister Konoe then offered to meet with Roosevelt, but Roosevelt insisted on reaching an agreement before any meeting. The American ambassador to Japan repeatedly urged Roosevelt to accept the meeting, warning that it was the only way to preserve the conciliatory Konoe government and peace in the Pacific. However, his recommendation was not acted upon. The Konoe government collapsed the following month when the Japanese military rejected a withdrawal of all troops from China.
Japan's final proposal, delivered on November 20, offered to withdraw from southern Indochina and to refrain from attacks in Southeast Asia, so long as the United States, United Kingdom, and Netherlands supplied one million U.S. gallons (3.8 million liters) of aviation fuel, lifted their sanctions against Japan, and ceased aid to China. The American counter-proposal of November 26 (November 27 in Japan), the Hull note, required Japan to completely evacuate China without conditions and conclude non-aggression pacts with Pacific powers. On November 26 in Japan, the day before the note's delivery, the Japanese task force left port for Pearl Harbor.
The Japanese intended the attack as a preventive action to keep the United States Pacific Fleet from interfering with their planned military actions in Southeast Asia against overseas territories of the United Kingdom, the Netherlands, and the United States. Over the course of seven hours, there were coordinated Japanese attacks on the American-held Philippines, Guam, and Wake Island and on the British Empire in Malaya, Singapore, and Hong Kong. From the Japanese point of view, it was seen as a preemptive strike "before the oil gauge ran empty."
Preliminary planning for an attack on Pearl Harbor to protect the move into the "Southern Resource Area", the Japanese term for the Dutch East Indies and Southeast Asia generally, began early in 1941 under the auspices of Admiral Isoroku Yamamoto, then commanding Japan's Combined Fleet. He won assent to formal planning and training for an attack from the Imperial Japanese Navy General Staff only after much contention with Naval Headquarters, including a threat to resign his command. Full-scale planning was underway by early spring 1941, primarily by Rear Admiral Ryūnosuke Kusaka, with assistance from Commander Minoru Genda and Yamamoto's Deputy Chief of Staff, Captain Kameto Kuroshima. The planners studied the 1940 British air attack on the Italian fleet at Taranto intensively.
Over the next several months, pilots were trained, equipment was adapted, and intelligence was collected. Despite these preparations, Emperor Hirohito did not approve the attack plan until November 5, after the third of four Imperial Conferences called to consider the matter. At first, he hesitated to engage in war but eventually authorized the Pearl Harbor strike despite dissent from certain advisors. Final authorization was not given by the emperor until December 1, after a majority of Japanese leaders advised him the Hull note would "destroy the fruits of the China incident, endanger Manchukuo and undermine Japanese control of Korea". Before the attack, he became more involved in military matters, even joining the Conference of Military Councillors, which was considered unusual for him. Additionally, he actively sought more information about the war plans. According to an aide, he openly displayed happiness upon hearing about the success of the surprise attacks.
By late 1941, many observers believed that hostilities between the United States and Japan were imminent. A Gallup poll just before the attack on Pearl Harbor found that 52% of Americans expected war with Japan, 27% did not, and 21% had no opinion. While American Pacific bases and facilities had been placed on alert on many occasions, officials doubted Pearl Harbor would be the first target; instead, they expected the Philippines to be attacked first. This presumption was due to the threat that the air bases throughout the country and the naval base at Manila posed to sea lanes, as well as to the shipment of supplies to Japan from territory to the south. They also incorrectly believed that Japan was not capable of mounting more than one major naval operation at a time.
The Japanese attack had several major aims. First, it intended to destroy important American fleet units, thereby preventing the Pacific Fleet from interfering with the Japanese conquest of the Dutch East Indies and Malaya and enabling Japan to conquer Southeast Asia without interference. The leaders of the Imperial Japanese Navy (IJN) subscribed to Alfred Thayer Mahan's "decisive battle" doctrine, especially that of destroying the maximum number of battleships. Second, it was hoped to buy time for Japan to consolidate its position and increase its naval strength before shipbuilding authorized by the 1940 Vinson-Walsh Act erased any chance of victory. Third, to deliver a blow to America's ability to mobilize its forces in the Pacific, battleships were chosen as the main targets, since they were the prestige ships of navies at the time. Finally, it was hoped that the attack would undermine American morale to such an extent that the American government would drop its demands contrary to Japanese interests and seek a peace compromise.
Striking the Pacific Fleet at anchor in Pearl Harbor had two distinct disadvantages: the targeted ships would be in very shallow water, so it would be relatively easy to salvage and possibly repair them, and most of the crews would survive the attack since many would be on shore leave or would be rescued from the harbor. A further important disadvantage was the absence of all three of the Pacific Fleet's aircraft carriers (Enterprise, Lexington, and Saratoga). Despite these concerns, Yamamoto decided to press ahead.
Japanese confidence in their ability to win a short war meant that other targets in the harbor, especially the navy yard, oil tank farms and submarine base, were left unscathed, since by their thinking the war would be over before the influence of these facilities would be felt.
On November 26, 1941, a Japanese task force (the Striking Force) of six aircraft carriers – Akagi, Kaga, Sōryū, Hiryū, Shōkaku, and Zuikaku – departed Hittokapu Bay on Etorofu (now Iterup) Island in the Kuril Islands, en route to a position northwest of Hawaii, intending to launch its 408 aircraft to attack Pearl Harbor: 360 for the two attack waves and 48 on defensive combat air patrol (CAP), including nine fighters from the first wave.
The first wave was to be the primary attack, while the second wave was to attack carriers as its first objective and cruisers as its second, with battleships as the third target. The first wave carried most of the weapons designed to attack capital ships, mainly specially adapted Type 91 aerial torpedoes which were designed with an anti-roll mechanism and a rudder extension that let them operate in shallow water. The aircrews were ordered to select the highest-value targets (battleships and aircraft carriers) or, if these were not present, any other high-value ships (cruisers and destroyers). First-wave dive bombers were to attack ground targets. Fighters were ordered to strafe and destroy as many parked aircraft as possible to ensure they did not intercept the bombers, especially in the first wave. When the fighters' fuel got low, they were to refuel aboard the aircraft carriers and return to combat. Fighters were to assume CAP duties where needed, especially over American airfields.
Before the attack commenced, the Imperial Japanese Navy launched reconnaissance floatplanes from heavy cruisers Chikuma and Tone, to scout Oahu and Lahaina Roads, Maui, respectively, with orders to report on American fleet composition and location. Reconnaissance aircraft flights risked alerting the Americans, and were not necessary. Fleet composition and preparedness information in Pearl Harbor were already known from the reports of the Japanese spy Takeo Yoshikawa. A report of the absence of the American fleet at Lahaina anchorage off Maui was received from the Tone's floatplane and the fleet submarine I-72. Another four scout planes patrolled the area between the Japanese carrier force (the Kidō Butai) and Niihau, to detect any counterattack.
Fleet submarines I-16, I-18, I-20, I-22, and I-24 each embarked a Type A midget submarine for transport to the waters off Oahu. The five I-boats left Kure Naval District on November 25, 1941. On December 6, they came to within 10 nmi (19 km; 12 mi) of the mouth of Pearl Harbor and launched their midget subs at about 01:00 local time on December 7. At 03:42 Hawaiian time, the minesweeper Condor spotted a midget submarine periscope southwest of the Pearl Harbor entrance buoy and alerted the destroyer Ward. The midget may have entered Pearl Harbor. However, Ward sank another midget submarine at 06:37 in the first American shots in the Pacific Theater. A midget submarine on the north side of Ford Island missed the seaplane tender Curtiss with her first torpedo and missed the attacking destroyer Monaghan with her other one before being sunk by Monaghan at 08:43.
A third midget submarine, Ha-19, grounded twice, once outside the harbor entrance and again on the east side of Oahu, where it was captured on December 8. Ensign Kazuo Sakamaki swam ashore and was captured by Hawaii National Guard Corporal David Akui, becoming the first Japanese prisoner of war. A fourth had been damaged by a depth charge attack and was abandoned by its crew before it could fire its torpedoes. It was found outside the harbor in 1960. Japanese forces received a radio message from a midget submarine at 00:41 on December 8 claiming to have damaged one or more large warships inside Pearl Harbor.
In 1992, 2000, and 2001 Hawaii Undersea Research Laboratory's submersibles found the wreck of the fifth midget submarine lying in three parts outside Pearl Harbor. The wreck was in the debris field where much surplus American equipment had been dumped after the war, including vehicles and landing craft. Both of its torpedoes were missing. This correlates with reports of two torpedoes fired at the light cruiser St. Louis at 10:04 at the entrance of Pearl Harbor, and a possible torpedo fired at destroyer Helm at 08:21. There is dispute over this official chain of events though. The "torpedo" that St. Louis saw was also reportedly a porpoising minesweeping float being towed by the destroyer Boggs. Some historians and naval architects theorise that a photo taken by a Japanese naval aviator of Battleship Row during the attack on Pearl Harbor that was declassified in the 1990s and publicized in the 2000s to the public, shows the fifth midget submarine firing a torpedo at West Virginia and another at Oklahoma. These torpedoes were twice the size of the aerial torpedoes so it was possible that both torpedoes heavily contributed to the sinkings of both ships and especially helped to capsize Oklahoma as Oklahoma was the only battleship that day to suffer catastrophic damage to her belt armor at the waterline from a torpedo. Admiral Chester Nimitz, in a report to Congress, confirmed that one midget submarine's torpedo (possibly from the other midget submarine that fired torpedoes but failed to hit a target) which was fired but did not explode was recovered in Pearl Harbor and was much larger than the aerial torpedoes. Others dispute this theory.
The attack took place before any formal declaration of war was made by Japan, but this was not Admiral Yamamoto's intention. He originally stipulated that the attack should not commence until thirty minutes after Japan had informed the United States that peace negotiations were at an end. However, the attack began before the notice could be delivered. Tokyo transmitted the 5000-word notification (commonly called the "14-Part Message") in two blocks to the Japanese Embassy in Washington. Transcribing the message took too long for the Japanese ambassador to deliver it at 1:00 p.m. Washington time, as ordered, and consequently the message was not presented until more than one hour after the attack had begun — but American code breakers had already deciphered and translated most of the message hours before it was scheduled to be delivered. The final part of the message is sometimes described as a declaration of war. While it was viewed by a number of senior American government and military officials as a very strong indicator negotiations were likely to be terminated and that war might break out at any moment, it neither declared war nor severed diplomatic relations. A declaration of war was printed on the front page of Japan's newspapers in the evening edition of December 8 (late December 7 in the United States), but not delivered to the American government until the day after the attack.
For decades, conventional wisdom held that Japan attacked without first formally breaking diplomatic relations only because of accidents and bumbling that delayed the delivery of a document hinting at war to Washington. In 1999, however, Takeo Iguchi, a professor of law and international relations at International Christian University in Tokyo, discovered documents that pointed to a vigorous debate inside the government over how, and indeed whether, to notify Washington of Japan's intention to break off negotiations and start a war, including a December 7 entry in the war diary saying, "[O]ur deceptive diplomacy is steadily proceeding toward success." Of this, Iguchi said, "The diary shows that the army and navy did not want to give any proper declaration of war, or indeed prior notice even of the termination of negotiations ... and they clearly prevailed."
In any event, even if the Japanese had decoded and delivered the 14-Part Message before the beginning of the attack, it would not have constituted either a formal break of diplomatic relations or a declaration of war. The final two paragraphs of the message read:
United States naval intelligence officers were alarmed by the unusual timing for delivering the message — 1:00 p.m. on a Sunday, which was 7:30 a.m. in Hawaii — and attempted to alert Pearl Harbor. But due to communication problems the warning was not delivered before the attack.
The first attack wave of 183 airplanes, led by Commander Mitsuo Fuchida, was launched north of Oahu. Six airplanes failed to launch due to technical difficulties. The first wave included three groups of airplanes:
As the first wave approached Oahu, it was detected by United States Army SCR-270 radar positioned at Opana Point near the island's northern tip. This post had been in training mode for months, but was not yet operational. The operators, Privates George Elliot Jr. and Joseph Lockard, reported a target to Private Joseph P. McDonald, a private stationed at Fort Shafter's Intercept Center near Pearl Harbor. Lieutenant Kermit A. Tyler, a newly assigned officer at the thinly manned Intercept Center, presumed it was the scheduled arrival of six B-17 bombers from California. The Japanese planes were approaching from a direction very close (only a few degrees difference) to the bombers, and while the operators had never seen a formation as large on radar, they neglected to tell Tyler of its size. Tyler, for security reasons, could not tell the operators of the six B-17s that were due (even though it was widely known).
As the first wave approached Oahu, they encountered and shot down several American aircraft. At least one of these radioed a somewhat incoherent warning. Other warnings from ships off the harbor entrance were still being processed or awaiting confirmation when the Japanese air assault began at 7:48 a.m. Hawaiian time (3:18 a.m. December 8 Japanese Standard Time, as kept by ships of the Kido Butai), with the attack on Kaneohe. A total of 353 Japanese planes reached Oahu in two waves. Slow, vulnerable torpedo bombers led the first wave, exploiting the first moments of surprise to attack the most important ships present (the battleships), while dive bombers attacked American air bases across Oahu, starting with Hickam Field, the largest, and Wheeler Field, the main United States Army Air Forces fighter base. The 171 planes in the second wave attacked the Army Air Forces' Bellows Field, near Kaneohe on the windward side of the island, and Ford Island. The only aerial opposition came from a handful of P-36 Hawks, P-40 Warhawks and some SBD Dauntless dive bombers from the carrier Enterprise.
In the first-wave attack, about eight of the forty-nine 800‑kg (1760 lb) armor-piercing bombs dropped hit their intended battleship targets. At least two of those bombs broke up on impact, another detonated before penetrating an unarmored deck, and one was a dud. Thirteen of the forty torpedoes hit battleships, while four hit other ships. Men aboard the ships awoke to the sounds of alarms, bombs exploding, and gunfire, prompting them to dress as they ran to General Quarters stations. (The famous message, "Air raid Pearl Harbor. This is not drill.", was sent from the headquarters of Patrol Wing Two, the first senior Hawaiian command to respond.) American servicemen were caught unprepared by the attack. Ammunition lockers were locked, aircraft parked wingtip to wingtip in the open to prevent sabotage, guns unmanned (none of the Navy's 5"/38s, only a quarter of its machine guns, and only four of 31 Army batteries got in action). Despite this low alert status, many American military personnel responded effectively during the attack. Ensign Joseph Taussig Jr., aboard Nevada, commanded the ship's antiaircraft guns and was severely wounded but remained at his post. Lieutenant Commander F. J. Thomas commanded Nevada in the captain's absence and got her underway until the ship was grounded at 9:10 a.m. One of the destroyers, Aylwin, got underway with only four officers aboard, all ensigns, none with more than a year's sea duty; she operated at sea for 36 hours before her commanding officer managed to get back aboard. Captain Mervyn Bennion, commanding West Virginia, led his men until he was cut down by fragments from a bomb which hit Tennessee, moored alongside.
The second planned wave consisted of 171 planes: 54 B5Ns, 81 D3As, and 36 A6Ms, commanded by Lieutenant-Commander Shigekazu Shimazaki. Four planes failed to launch because of technical difficulties. This wave and its targets also comprised three groups of planes:
The second wave was divided into three groups. One was tasked to attack Kāneʻohe, the rest Pearl Harbor proper. The separate sections arrived at the attack point almost simultaneously from several directions.
Ninety minutes after it began, the attack was over. 2,008 sailors were killed and 710 others wounded; 218 soldiers and airmen (who were part of the Army prior to the independent United States Air Force in 1947) were killed and 364 wounded; 109 Marines were killed and 69 wounded; and 68 civilians were killed and 35 wounded. In total, 2,403 Americans were killed, and 1,178 were wounded. Eighteen ships were sunk or run aground, including five battleships. All of the Americans killed or wounded during the attack were legally non-combatants, given that there was no state of war when the attack occurred.
Of the American fatalities, nearly half were due to the explosion of Arizona's forward magazine after she was hit by a modified 16-inch (410 mm) shell. Author Craig Nelson wrote that the vast majority of the U.S. sailors killed at Pearl Harbor were junior enlisted personnel. "The officers of the Navy all lived in houses and the junior people were the ones on the boats, so pretty much all of the people who died in the direct line of the attack were very junior people", Nelson said. "So everyone is about 17 or 18 whose story is told there."
Among the notable civilian casualties were nine Honolulu Fire Department firefighters who responded to Hickam Field during the bombing in Honolulu, becoming the only fire department members on American soil to be attacked by a foreign power in history. Fireman Harry Tuck Lee Pang of Engine 6 was killed near the hangars by machine-gun fire from a Japanese plane. Captains Thomas Macy and John Carreira of Engine 4 and Engine 1, respectively, died while battling flames inside the hangar after a Japanese bomb crashed through the roof. An additional six firefighters were wounded by Japanese shrapnel. The wounded later received Purple Hearts (originally reserved for service members wounded by enemy action while partaking in armed conflicts) for their peacetime actions that day on June 13, 1944; the three firefighters killed did not receive theirs until December 7, 1984, on the 43rd anniversary of the attack. This made the nine men the only non-military firefighters to receive such an award in American history.
Already damaged by a torpedo and on fire amidships, Nevada attempted to exit the harbor. She was targeted by many Japanese bombers as she got under way and sustained more hits from 250 lb (113 kg) bombs, which started further fires. She was deliberately beached to avoid risking blocking the harbor entrance if she sank there. California was hit by two bombs and two torpedoes. The crew might have kept her afloat, but were ordered to abandon ship just as they were raising power for the pumps. Burning oil from Arizona and West Virginia was drifted down toward her and probably made the situation look worse than it was. The disarmed target ship Utah was holed twice by torpedoes. West Virginia was hit by seven torpedoes, the seventh tearing away her rudder. Oklahoma was hit by four torpedoes, the last two above her belt armor, which caused her to capsize. Maryland was hit by two of the converted 16" shells, but neither caused serious damage.
Although the Japanese concentrated on battleships (the largest vessels present), they did not ignore other targets. The light cruiser Helena was torpedoed, and the concussion from the blast capsized the neighboring minelayer Oglala. Two destroyers in dry dock, Cassin and Downes, were destroyed when bombs penetrated their fuel bunkers. The leaking fuel caught fire; flooding the dry dock in an effort to fight fire made the burning oil rise, and both were burned out. Cassin slipped from her keel blocks and rolled against Downes. The light cruiser Raleigh was holed by a torpedo. The light cruiser Honolulu was damaged but remained in service. The repair vessel Vestal, moored alongside Arizona, was heavily damaged and beached. The seaplane tender Curtiss was also damaged. The destroyer Shaw was badly damaged when two bombs penetrated her forward magazine.
Of the 402 American aircraft in Hawaii, 188 were destroyed and 159 damaged, 155 of them on the ground. Almost none were actually ready to take off to defend the base. Eight Army Air Forces pilots managed to get airborne during the attack, and six were credited with downing at least one Japanese aircraft during the attack: 1st Lieutenant Lewis M. Sanders and 2nd Lieutenants Philip M. Rasmussen, Kenneth M. Taylor, George S. Welch, Harry W. Brown, and Gordon H. Sterling Jr. Of 33 Consolidated PBY Catalinas in Hawaii, 30 were destroyed, while three on patrol at the time of the attack returned undamaged. Friendly fire brought down some American planes on top of that, including four from an inbound flight from Enterprise.
At the time of the attack, nine civilian aircraft were flying in the vicinity of Pearl Harbor. Of these, three were shot down.
Fifty-five Japanese airmen and nine submariners were killed in the attack, and one, Kazuo Sakamaki, was captured. Of Japan's 414 available planes, 350 took part in the raid. Twenty-nine were lost, nine in the first wave (three fighters, one dive bomber, and five torpedo bombers) and twenty in the second (six fighters and fourteen dive bombers), with another 74 damaged by antiaircraft fire from the ground.
According to some accounts, several Japanese junior officers, including Fuchida and Genda, urged Nagumo to carry out a third strike in order to sink more of the Pearl Harbor's remaining warships, and damage the base's maintenance shops, drydock facilities and oil tank yards. Most notably, Fuchida gave a firsthand account of this meeting several times after the war. However, some historians have cast doubt on this and many other of Fuchida's later claims, which sometimes conflict with documented historic records. Genda, who opined during the planning for the attack that without an invasion three strikes were necessary to fully disable the Pacific Fleet, denied requesting an additional attack. Regardless, it is undisputed that the captains of the other five carriers in the task force reported they were willing and ready to carry out a third strike soon after the second returned, but Nagumo decided to withdraw for several reasons:
Although a hypothetical third strike would have likely focused on the base's remaining warships, military historians have suggested any potential damage to the shore facilities would have hampered the Pacific Fleet far more seriously. If they had been wiped out, "serious [American] operations in the Pacific would have been postponed for more than a year"; according to Admiral Chester W. Nimitz, later Commander in Chief of the Pacific Fleet, "it would have prolonged the war another two years".
At a conference aboard his flagship the following morning, Yamamoto supported Nagumo's withdrawal without launching a third wave. In retrospect, sparing the vital dockyards, maintenance shops, and the oil tank farm meant the United States could respond relatively quickly in the Pacific. Yamamoto later regretted Nagumo's decision to withdraw and categorically stated it had been a great mistake not to order a third strike.
Twenty-one American ships were damaged or lost in the attack, of which all but three were repaired and returned to service.
After a systematic search for survivors, Captain Homer N. Wallin was ordered to lead a formal salvage operation.
Around Pearl Harbor, divers from the Navy (shore and tenders), the Pearl Harbor Naval Shipyard, and civilian contractors (Pacific Bridge Company and others) began work on the ships that could be refloated. They patched holes, cleared debris, and pumped water out of ships. Melvin Storer and other Navy divers worked inside the damaged ships. Within six months, five battleships and two cruisers were patched or refloated so they could be sent to shipyards in Pearl Harbor and on the mainland for extensive repair.
Intensive salvage operations continued for another year, a total of some 20,000 man-hours under water. Arizona and the target ship Utah were too heavily damaged for salvage and remain where they were sunk, with Arizona becoming a war memorial. Oklahoma, while successfully raised, was never repaired and capsized while under tow to the mainland in 1947. The Nevada proved particularly difficult to raise and repair; two men involved in the operation died after inhaling poisonous gases that had accumulated in the ship's interior. When feasible, armament and equipment were removed from vessels too damaged to repair and put to use to improve the anti-aircraft defense of the harbor or installed aboard other craft.
The initial announcement of the attack on Pearl Harbor was made by the White House Press Secretary, Stephen Early, at 2:22 p.m. Eastern time (8:52 a.m. Hawaiian time): "The Japanese have attacked Pearl Harbor from the air and all naval and military activities on the island of Oahu, principal American base in the Hawaiian islands." As information developed, Early made a number of additional announcements to approximately 150 White House reporters over the course of the afternoon.
Initial reports of the attack moved on news wires at approximately 2:25 p.m. Eastern time. The first radio coverage (which, at the time, represented the earliest opportunity for ordinary people to learn of the attack) was on the CBS radio network's scheduled news program, World News Today, at 2:30 p.m. Eastern time. John Charles Daly read the initial report, then switched to London, where Robert Trout ad-libbed on the possible London reaction. The first report on NBC cut into a play, a dramatization of The Inspector-General, at 2:33 p.m. Eastern time and lasted only 21 seconds. Unlike the later practice with major news stories, there were only brief interruptions of scheduled commercial programming.
The attacks were covered on television but the extent of it was limited; as commercial television had started just 6 months earlier, "a few thousand TV sets existed" in the United States, with most being in the Greater New York City area, and only a handful of stations existed which were all in New York, Chicago, Los Angeles and Philadelphia. WNBT from New York was the only TV station that was regularly airing that day in the country, with the comedy movie Millionaire Playboy, which was scheduled for 3:30-4:30 PM, being interrupted with the news of the attack. The other station known to cover the attacks was WCBW, also out of New York, where a special report on the attack was broadcast that evening. There are no recordings of either station's coverage, either visual or audio.
A contemporaneous newspaper report compared the attack to the Battle of Port Arthur in which the Imperial Japanese Navy attacked the Imperial Russian Navy, triggering the Russo-Japanese War, 37 years prior. Modern writers have continued to note parallels between the attacks, albeit more dispassionately.
News of the attack was first broadcast at 11:30 AM (Japanese Standard Time), however it had already been announced "shortly after" 7 AM (Japanese Standard Time) that Japan had "entered into a situation of war with the United States and Britain in the Western Pacific before dawn". There was no further elaboration or explanation, and the attacks were already finished by that time. The attack on Pearl Harbor was eventually covered in the Japanese press, but press in wartime Japan was heavily censored. One Japanese newspaper, The Asahi Shimbun did report on the attack the day it occurred, and from that point onward their editorials began to back governmental decisions regardless of what they were. The Asahi Shimbun also reported the declaration of war on the United States after the attacks, framing it as an Imperial Order, with most Japanese people taking it that way. In contrast, coverage in the New York Times focused on "the danger to democracy and to the nation" brought on by the Japanese attack. NHK broadcast twelve special news reports along with its six regularly scheduled ones that day. NHK covered the news of Pearl Harbor and other attacks positively throughout the rest of the month.
The United Kingdom's BBC broadcast news of the attack and that Manila was also under attack.
The day after the attack, U.S. President Franklin D. Roosevelt delivered his famous Day of Infamy speech to a Joint Session of Congress, calling for a formal declaration of war on the Empire of Japan. Congress obliged his request less than an hour later. On December 11, Germany and Italy declared war on the United States, even though the Tripartite Pact did not require it. Congress issued a declaration of war against Germany and Italy later that same day.
The United Kingdom had already been at war with Germany since September 1939 and with Italy since June 1940, and British Prime Minister Winston Churchill had promised to declare war "within the hour" of a Japanese attack on the United States. Upon learning of the Japanese attacks on Malaya, Singapore, and Hong Kong, Churchill promptly determined there was no need to either wait or further consult the US government and immediately summoned the Japanese Ambassador. As a result, the United Kingdom declared war on Japan nine hours before the United States did.
The attack was an initial shock to all the Allies in the Pacific Theater. Further losses compounded the alarming setback. Japan attacked the Philippines hours later (because of the time difference, it was December 8 in the Philippines). Only three days after the attack on Pearl Harbor, the battleship Prince of Wales and battlecruiser Repulse were sunk off the coast of Malaya, causing Churchill later to recollect "In all the war I never received a more direct shock. As I turned and twisted in bed the full horror of the news sank in upon me. There were no British or American capital ships in the Indian Ocean or the Pacific except the American survivors of Pearl Harbor who were hastening back to California. Over this vast expanse of waters, Japan was supreme and we everywhere were weak and naked."
Throughout the war, Pearl Harbor was frequently used in American propaganda.
One further consequence of the attack on Pearl Harbor and its aftermath (notably the Niihau incident) was that Japanese-American residents and citizens were relocated to nearby Japanese-American internment camps. Within hours of the attack, hundreds of Japanese-American leaders were rounded up and taken to high-security camps such as Sand Island at the mouth of Honolulu harbor and Kilauea Military Camp on the island of Hawaii. Eventually, more than 110,000 Japanese Americans, nearly all who lived on the West Coast, were forced into interior camps, but in Hawaii, where the 150,000-plus Japanese Americans composed over one-third of the population, only 1,200 to 1,800 were interned.
The attack also had international consequences. The Canadian province of British Columbia, bordering the Pacific Ocean, had long had a large population of Japanese immigrants and their Japanese-Canadian descendants. Pre-war tensions were exacerbated by the Pearl Harbor attack, leading to a reaction from the government of Canada. On February 24, 1942, Order-in-Council P.C. no. 1486 was passed under the War Measures Act, allowing for the forced removal of any and all Canadians of Japanese descent from British Columbia, as well as prohibiting them from returning to the province. On March 4, regulations under the act were adopted to evacuate Japanese Canadians. As a result, 12,000 were interned in interior camps, 2,000 were sent to road camps, and another 2,000 were forced to work in the prairies on sugar beet farms.
In the wake of the attack, fifteen Medals of Honor, fifty-one Navy Crosses, fifty-three Silver Stars, four Navy and Marine Corps Medals, one Distinguished Flying Cross, four Distinguished Service Crosses, one Distinguished Service Medal, and three Bronze Star Medals were awarded to the American servicemen who distinguished themselves in combat at Pearl Harbor. Additionally, a special military award, the Pearl Harbor Commemorative Medal, was later authorized for all military veterans of the attack.
Japanese planners of the Pearl Harbor attack had determined that some means were required for rescuing fliers whose aircraft were damaged too badly to return to the carriers. The island of Niihau, only thirty minutes by air from Pearl Harbor, was designated as the rescue point.
During the second wave, a Zero fighter flown by Petty Officer Shigenori Nishikaichi of Hiryu was damaged in the attack on Wheeler, so he flew to the rescue point. The aircraft was further damaged on his crash landing. Nishikaichi was helped from the wreckage by one of the Native Hawaiians, who, aware of the tension between the United States and Japan, took the pilot's pistol, maps, codes and other documents. The island's residents had no telephones or radios and were completely unaware of the attack on Pearl Harbor. Nishikaichi enlisted the support of three Japanese-American residents in an attempt to recover the documents. During the ensuing struggles, Nishikaichi was killed, and a Hawaiian civilian was wounded; one collaborator committed suicide, and his wife and the third collaborator were sent to prison.
The ease with which the local ethnic Japanese residents had apparently gone to Nishikaichi's assistance was a source of concern for many and tended to support those who believed that local Japanese could not be trusted.
Rear Admiral Chūichi Hara summed up the Japanese result by saying, "We won a great tactical victory at Pearl Harbor and thereby lost the war."
While the attack accomplished its intended objective, it turned out to be largely unnecessary. Unbeknownst to Yamamoto, who conceived the original plan, the United States Navy had decided as far back as 1935 to abandon "charging" across the Pacific towards the Philippines in response to an outbreak of war (in keeping with the evolution of Plan Orange). The United States instead adopted "Plan Dog" in 1940, which emphasized keeping the IJN out of the eastern Pacific and away from the shipping lanes to Australia, while the United States concentrated on defeating Nazi Germany.
Fortunately for the United States, the American aircraft carriers were untouched; otherwise the Pacific Fleet's ability to conduct offensive operations would have been crippled for a year or more (given no diversions from the Atlantic Fleet). As it was, the Navy was left with no choice but to rely on carriers and submarines. While six of the eight battleships were repaired and returned to service, their relatively low speed and high fuel consumption limited their deployment, and they served mainly in shore bombardment roles (their only major action being the Battle of Surigao Strait in October 1944). A major flaw in Japanese strategic thinking was a belief that the ultimate Pacific battle would be fought by battleships, in keeping with the doctrine of Captain Alfred Thayer Mahan. As a result, Yamamoto (and his successors) hoarded battleships for a "decisive battle" that never happened.
The Japanese confidence in their ability to win a quick victory meant that they neglected Pearl Harbor's navy repair yards, oil tank farms, submarine base and old headquarters building. All of these targets were omitted from Genda's list, yet they proved more important than any battleship to the American war effort in the Pacific. The survival of the repair shops and fuel depots allowed Pearl Harbor to maintain logistical support of the Navy, such as the Doolittle Raid and the Battles of the Coral Sea and Midway. It was submarines that immobilized the Imperial Japanese Navy's heavy ships and brought Japan's economy to a virtual standstill by crippling the importation of oil and raw materials: by the end of 1942, the amount of raw materials brought in was cut in half, "to a disastrous ten million tons", while oil "was almost completely stopped". Lastly, the basement of the Old Administration Building was the home of the cryptanalytic unit which contributed significantly to the Midway ambush and the Submarine Force's success.
Ever since the Japanese attack, there has been debate as to how and why the United States had been caught unaware, and how much and when American officials knew of Japanese plans and related topics. As early as 1924, Chief of United States Air Service Mason Patrick showed concern for military vulnerabilities in the Pacific, having sent General Billy Mitchell on a survey of the Pacific and the East. Patrick called Mitchell's subsequent report, which identified vulnerabilities in Hawaii, a "theoretical treatise on employment of airpower in the Pacific, which, in all probability undoubtedly will be of extreme value some 10 or 15 years hence".
At least two naval war games, one in 1932 and another in 1936, proved that Pearl was vulnerable to such an attack. Admiral James Richardson was removed from command shortly after protesting President Roosevelt's decision to move the bulk of the Pacific fleet to Pearl Harbor. The decisions of military and political leadership to ignore these warnings have contributed to conspiracy theories. Several writers, including decorated World War II veteran and journalist Robert Stinnett, author of Day of Deceit, and former United States Rear Admiral Robert Alfred Theobald, author of The Final Secret of Pearl Harbor: The Washington Background of the Pearl Harbor Attack, have argued that various parties high in the American and British governments knew of the attack in advance and may even have let it happen or encouraged it in order to force the United States into the war via the so-called "back door". However, this conspiracy theory is rejected by mainstream historians.
The theory that the Americans were warned in advance, however, is supported by statements made by Dick Ellis, a British-Australian intelligence officer for MI6 who helped William J. Donovan set up the Office of Strategic Services. Ellis was deputy to William Stephenson at British Security Co-ordination. In Jesse Fink's 2023 biography of Ellis, The Eagle in the Mirror, Ellis is quoted as saying: "[Stephenson] was convinced from the information that was reaching him that this attack was imminent, and through Jimmy Roosevelt, President Roosevelt's son, he passed this information to the President. Now whether the President at that time had other information which corroborated this... it's impossible to say."