Attack on Pearl Harbor Part I

 The attack on Pearl Harbor was a surprise military strike by the Imperial Japanese Navy Air Service on the American naval base at Pearl Harbor in Honolulu, Hawaii, the United States, just before 8:00 a.m. (local time) on Sunday, December 7, 1941. At the time, the United States was a neutral country in World War II. The attack on Hawaii and other U.S. territories led the United States to formally enter World War II on the side of the Allies the day following the attack, on December 8, 1941. The Japanese military leadership referred to the attack as the Hawaii Operation and Operation AI, and as Operation Z during its planning.

The Empire of Japan's attack on Pearl Harbor was preceded by months of negotiations between the United States and Japan over the future of the Pacific. Japanese demands included that the United States 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. Anticipating a negative response, Japan sent out its naval attack groups in November 1941 just prior to receiving the Hull note—which states the United States desire that Japan withdraw from China and French Indochina. Japan intended the attack as a preventive action. Its aim was to prevent the United States Pacific Fleet from interfering with its 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, Japan conducted 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 on Pearl Harbor started at 7:48 a.m. Hawaiian time (6:18 p.m. GMT). The base was attacked by 353 Imperial Japanese aircraft (including fighters, level and dive bombers, and torpedo bombers) in two waves, launched from six aircraft carriers. Of the eight United States Navy battleships present, all were damaged and four were sunk. All but USS Arizona were later raised, and six were returned to service and went on to fight in the war. The Japanese also sank or damaged three cruisers, three destroyers, an anti-aircraft training ship, and one minelayer. More than 180 US aircraft were destroyed. A total of 2,393 Americans were killed and 1,178 others were wounded, making it the deadliest event ever recorded in Hawaii. It was also the deadliest foreign attack against the United States in its history until the September 11 attacks of 2001. Important base installations, such as the power station, dry dock, shipyard, maintenance, and fuel and torpedo storage facilities, as well as the submarine piers and headquarters building (also home of the intelligence section) were not attacked. Japanese losses were light: 29 aircraft and five midget submarines were lost, and 129 servicemen killed. Kazuo Sakamaki, the commanding officer of one of the submarines, was captured.

Japan declared war on the United States and the British Empire later that day (December 8 in Tokyo), but the declarations were not delivered until the following day. The British government declared war on Japan immediately after learning that their territory had also been attacked, while the following day (December 8), the United States Congress 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 the unannounced military action by Japan, the lack of any formal warning, as required by the Hague Convention of 1907, and the perception that the attack had been unprovoked, led then-President Franklin D. Roosevelt, in the opening line of his speech to a Joint Session of Congress the following day, to famously label December 7, 1941, "a date which will live in infamy".

Background

Diplomacy

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.

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."

Military planning

The Empire of Japan's 1941 attack plan on Pearl Harbor

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.

Objectives

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) ascribed 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.

Approach and attack

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.

Submarines

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 porpoising minesweeping floats being towed by the destroyer Boggs. Some historians and naval architects theorize 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,[86] 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.

Japanese declaration of war

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 governments 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:

Thus the earnest hope of the Japanese Government to adjust Japanese-American relations and to preserve and promote the peace of the Pacific through cooperation with the American Government has finally been lost.

The Japanese Government regrets to have to notify hereby the American Government that in view of the attitude of the American Government it cannot but consider that it is impossible to reach an agreement through further negotiations.

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.

First wave composition

The Japanese attacked in two waves. The first wave was detected by United States Army radar at 136 nautical miles (252 km), but was misidentified as United States Army Air Forces bombers arriving from the American mainland.

Top: A: Ford Island NAS. B: Hickam Field. C: Bellows Field. D: Wheeler Field. E: Kaneohe NAS. F: Ewa MCAS. R-1: Opana Radar Station. R-2: Kawailoa RS. R-3: Kaaawa RS. G: Kahuku. H: Haleiwa. I: Wahiawa. J: Kaneohe. K: Honolulu. 0: B-17s from mainland. 1: First strike group. 1-1: Level bombers. 1–2: Torpedo bombers. 1–3: Dive bombers. 2: Second strike group. 2-1: Level bombers. 2-1F: Fighters. 2-2: Dive bombers.

Bottom: A: Wake Island. B: Midway Islands. C: Johnston Island. D: Hawaii. D-1: Oahu. 1: Lexington. 2: Enterprise. 3: First Air Fleet.

 

  City   Army base   Navy base

Attacked targets: 1: USS California. 2: USS Maryland. 3: USS Oklahoma. 4: USS Tennessee. 5: USS West Virginia. 6: USS Arizona. 7: USS Nevada. 8: USS Pennsylvania. 9: Ford Island NAS. 10: Hickam field.

Ignored infrastructure targets: A: Oil storage tanks. B: CINCPAC headquarters building. C: Submarine base. D: Navy Yard.

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:

1st Group (targets: battleships and aircraft carriers)

49 Nakajima B5N Kate bombers armed with 800‑kg (1760 lb) armor-piercing bombs, organized in four sections (one failed to launch)

40 B5N bombers armed with Type 91 torpedoes, also in four sections

2nd Group – (targets: Ford Island and Wheeler Field)

51 Aichi D3A Val dive bombers armed with 550 lb (249 kg) general-purpose bombs (3 failed to launch)

3rd Group – (targets: aircraft at Ford Island, Hickam Field, Wheeler Field, Barber's Point, Kaneohe)

43 Mitsubishi A6M "Zero" fighters for air control and strafing (2 failed to launch)

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.