The attack on Pearl Harbor ranks as the most successful military surprise attack in the early years of combined naval/aerial combat. On December 7, 1941 the Imperial Japanese Navy Air Service struck the United States naval base at Pearl Harbor, Hawaii Territory. The attack directly led to the United States’ entrance into World War Two. Japan quickly followed up the attack with the invasion of numerous Pacific Islands. They held them through several years of gruesome fighting.

Scroll down to read more about the attack or click below to read up on specific posts about the lead-up to the attacks and the aftermath.

Why Did Japan Attack Pearl Harbor?

(See main article: Why Did Japan Attack?)

The U.S. and Japan had been butting heads for decades and it was inevitable that things would eventually culminate into a war. Japan had imperial ambitions to expand to China to solve some demographical and economical problems and to take over the Chinese import market. When in 1937 Japan decided to declare war on China, America was very against this aggression and responded with trade embargoes and economic sanctions.

Specifically, the oil embargo that America organized with the British and the Dutch was a thorn in the side for Japan, which imported 90% of its oil. Without oil Japan’s military could not function and all war efforts would come to an end. Negotiations had been going on for months between Washington and Tokyo, without any resolution, so Japan decided to attack first.

As war was inevitable, Japan’s only chance was the element of surprise and to destroy America’s navy as quickly as possible. Japan wanted to move into the Dutch East Indies and Malaya to conquer territories that could provide important natural resources such as oil and rubber. By destroying a large portion of the American fleet, they hoped to conquer the Philippines and Malaya while America was still recovering from its own damages – simultaneous attacks were launched on these places while Pearl Harbor was taking place.

Ultimately, Japan hoped that America would accept defeat and that Japan could create a fortress that would stretch across the whole Pacific Rim.

Roosevelt’s Suspicions of an Attack

(See main article: Who Was President During the Attack?)

Roosevelt expected an attack by the Japanese, but conspiracy theories claiming that he knew that they were going to strike Pearl Harbor have been rejected by most scholars. The Government rather expected Japan to attack American targets in Thailand or the Dutch East Indies than a target this close to home. The Chicago Tribune published a top-secret war plan, “Rainbow Five” on December 4, 1941, in which the War Department made preparation arrangements for war with Japan.

On December 8, 1941 Franklin D. Roosevelt, delivered his “Infamy Speech” in which he called for war. He referred to the attack as a “date that will live in infamy.”

 

Intelligence Warnings of the Attack Before Dec. 7, 1941

(See main article: Warnings of the Attack)

The day before the death of Sara Roosevelt, Franklin Roosevelt’s mother, the State Department’s rebuff of Japanese Prime Minister Konoye’s urgent request for a private talk with Roosevelt convinced the Japanese to begin serious plans for an attack.

At a cabinet meeting on September 6, 1941, Admiral Isoroku Yamamoto was told to attack unless Konoye somehow achieved peace terms with the United States that would not spark a revolution at home, an uprising in Korea, or the restoration of Chinese morale. Hirohito had been shot at twice, once by a Japanese communist, once by a Korean nationalist. The better men of two cabinets had been murdered or wounded because they were seen as too accommodating to the foreigners who wanted to colonize Japan or reduce the nation that had never lost a war in modern times to a vulnerable third-rate power. Konoye himself had been threatened with assassination if he made too many concessions, and there had been serious attempts to overthrow the emperor in favor of his brother or his son. Hirohito knew that his dynasty itself could be wiped out like the Romanovs or marginalized, as the Japanese themselves had done to the Korean royalty, if he bowed to demands that the Japanese saw as not merely insulting but insane.

Yamamoto, who spoke fluent English, had studied at Harvard, and in happier times had hitchhiked across the United States, knew that Japan could not conquer, or even defeat, the United States. The Japanese grand strategy, if war could not be avoided, was to inflict enough damage and seize enough territory that the Americans would guarantee Japanese sovereignty in return for an armistice and restoration of all or most of what Japan had taken outside Korea and perhaps Manchuria.

Theoretical plans for a Japanese attack on Pearl Harbor had existed for decades. General Billy Mitchell had warned as early as 1924 that the next war would be fought with aircraft carriers. The U.S. Navy’s Admiral Harry Yarnell conducted a simulated attack by carrier-based aircraft in 1932 as part of a war game. The Navy judges ruled that it would have sustained substantial damage if the attack had been genuine, and the attackers won the war game.

Yamamoto had delivered his updated contingency plan for an attack on Pearl Harbor on January 7, 1941, less than a month after the British aerial torpedo attack on Taranto. Minoru Genda, Japan’s genius of planning, called Yamamoto’s initial plan “difficult but not impossible.” More information was needed. By the summer of 1941, Korean patriots who kept an ear to the wall at the Japanese consulate in Honolulu through Korean servants and loyal Japanese-Americans were picking up rumors of intense Japanese interest in the depth of water in the harbor and the strengths and weaknesses of Army and Navy installations in Hawaii.

Roosevelt’s restriction on Japan’s oil supply shifted Japanese planning into high gear. War was now the only alternative to economic strangulation and political revolution.

In the final months leading up to the attack, the U.S. government issued a memorandum stating, “The Japanese government does not desire or intend or expect to have forthwith armed conflict with the United States. . . . Were it a matter of placing bets, the undersigned would give odds of five to one that Japan and the United States will not be at ‘war’ on or before March 1 (a date more than 90 days from now, and after the period during which it has been estimated by our strategists that it would be to our advantage for us to have ‘time’ for further preparation and disposals).”

On December 1, 1941, the emperor met with his privy council. “It is now clear that Japan’s claims cannot be attained through diplomatic means,” Tojo said. The emperor—perhaps more gun-shy than the elder statesmen—asked for a vote. The cabinet voted unanimously for war. Hirohito agreed. The Japanese fleet was told to attack Pearl Harbor on December 7 unless it received a last-minute cancellation because of a sudden change in America’s attitude. Kurusu and Nomura—who had been sincere in seeking peace until they received the Hull note—were told to stall for time. Tojo summed up the situation: Japan, the one Asian, African, or South American nation that had modernized instead of being colonized, could not accept the American demands without riots at home, revolt in Korea, and reversal in Manchuria. “At this moment,” he declared, “our Empire stands on the threshold of glory or oblivion.”

Japan’s Strategy

(See main article: Japanese Strategy)

Japanese strategy in Pearl Harbor was based on relying on naval airpower over land-based planes. This is a customary approach to war today, but in 1941 it was a radically new form of warfare that challenged conventional wisdom in the still-early days of aerial combat.

The oceanic route to Pearl lay along a tangled path of diplomatic, military, and economic concerns. Japan, increasingly aggressive, began fighting China off-and-on in 1931, going at it full time starting in 1937. Tokyo’s aggression continued unchecked, and in 1941 it seemed aimed elsewhere—notably French Indochina and the Dutch East Indies. President Franklin D. Roosevelt took action, ordering an oil embargo in July, and the next month Washington warned the Japanese of possible consequences if they attacked nations beyond China.

Tokyo took little heed. Determined to avoid capitulation to what they considered foreign extortion, the cabinet of General Hideki Tojo opted for war. With less than two years of oil reserves, Tokyo had to act quickly and decisively.

Enter the aircraft carrier. It was the lynchpin of Japanese strategy.

Admiral Isoroku Yamamoto had risen to command the Combined Fleet in August 1939, days before the new war in Europe. An aviation advocate, he had supported Japan’s carrier program and, once committed to war, he backed the Hawaii Plan as preferable to the doctrinal “decisive battle” in mid-Pacific. He knew America well, having served there twice between the wars, and he realized that a pre-emptive strike was essential to the success of Japanese strategy—if success were possible at all.

Intensive training began in late August, affording Nagumo’s aircrews barely three months to perfect Japanese strategy in Pearl Harbor. Genda’s plan involved a triple blow: high-altitude level bombers, dive bombers, and torpedo planes. The Imperial Navy was well versed in all three, but the harbor presented a problem: the average depth was barely forty feet, and Japanese torpedoes needed twice as much to recover, rise to the desired depth, and run safely.

Ordnance engineers found an inspired solution. Large wooden surfaces were fitted to the torpedoes’ standard fins, providing larger surface areas. Once in the water the wooden fins were released and the Type 91 torpedoes sped on their way. Last-minute tests confirmed the theory.

On the morning of Sunday, December 7, 1941, the aircraft carrier was much like the proverbial musician who works twenty years to become an overnight sensation. When the Imperial Navy stunned the world with the attack on Pearl Harbor, Japan and the United States had two decades of experience operating carriers, perfecting equipment and techniques; thus it was no surprise that Japanese strategy was so advanced. Both navies had commissioned their first flattops in 1922, and they had experienced a parallel development.

The six Japanese carriers bound for Hawaiian waters were arrayed in pairs: the giant sisters Akagi and Kaga in the First Carrier Division; Soryu and Hiryu in the Second; and newly commissioned Shokaku and Zuikaku in the Fifth. They embarked some 420 bombers, torpedo planes, and fighters, while battleships and cruisers operated catapultlaunched floatplanes. The carriers were escorted by two battleships, three cruisers, nine destroyers, and nourished by seven tankers. The latter were more important than the fourteen escorts, as the striking force could not reach Hawaiian waters and return without replenishing at sea.

Kido Butai sortied from the Kurile Islands on November 26. Crossing the North Pacific under radio silence, the task force avoided detection during the ten-day transit. Meanwhile, submarines had already departed home waters and bases in the Marshall Islands.

Japanese strategy in Pearl Harbor was well-planned but at the same time put together at the last minute. Emperor Hirohito had approved war against the Western powers barely a month before the attack, but he did not grant approval for the Hawaii operation until December 1. Thus, Nagumo’s force represented an arrow launched at the heart of the U.S. Pacific Fleet that might have been recalled in flight. Instead, it flew straight to its target.

The first wave was timed to arrive over Pearl about thirty minutes after Japanese diplomats delivered Japan’s refusal to accept Washington’s demands. But the message from Tokyo took too long to decode, so the mission proceeded as a surprise. The attack precipitated boiling anger throughout America, fueling a surging rage that never abated until V-J Day.

While the leading squadrons winged southward, Kido Butai continued as briefed. At 7:15 the second wave of 168 planes lifted off its decks, comprising fifty-four level bombers, seventy-eight dive bombers, and thirty-six fighters.

Leading the whole group, Lieutenant Commander Murata’s torpedo bombers headed downward to launch their torpedoes, while Lieutenant Commander Itaya’s fighters raced forward to sweep enemy fighters from the air. Takahashi’s dive-bomber group had climbed for altitude and was out of sight. My bombers, meanwhile, made a circuit toward Barbers Point to keep pace with the attack schedule. No enemy fighters were in the air, nor were there any gun flashes from the ground.

The effectiveness of our attack was now certain, and a message, “Surprise attack successful!” was accordingly sent to Akagi at 0753. The message was received by the carrier and relayed to the homeland.

Once Fuchida signaled “Tora, tora, tora,” the Japanese strategy proceeded largely as planned. The first B5Ns over the target were sixteen from Soryu and Hiryu. Briefed to hit carriers on Ford Island’s northwest coast, they went for alternate objectives, destroying the target ship USS Utah (née BB-31, re-designated AG-16) and damaging a cruiser.

Akagi’s torpedo squadron led a devastating attack. The Nakajimas swept in from the north shore of the harbor, skimming low between Hickam Field and the fuel tank farm, then nudging downward over the water. Making one hundred mph at sixty-five feet, they deployed as per individual briefings and turned onto their attack headings. A quarter mile ahead lay the gray monoliths along Battleship Row.

Combined Army-Navy-Marine aircraft losses were about 175 immediately assessed as destroyed plus twenty-five damaged beyond repair. Some 150 sustained lesser damage.

The Japanese lost twenty-nine aircraft and sixty-five men, mostly aircrew, but including ten sailors in five miniature submarines.

Pearl Harbor was a rarity in history—a clearly defined day when the old order ended, abruptly, violently, and permanently. Not only had Kido Butai initiated a new way of warfare, but it upset the conventional wisdom that naval airpower could not compete with land-based planes. Japanese strategy was a complete disruption of aerial combat. Historian John Lundstrom did not exaggerate when he described Kido Butai as “a 1941 atomic bomb.” But retribution was coming.

 

Timing of the Attack

(See main article: When did the Attack Occur?)

The Attack took place during World War Two, almost halfway through the war, on the 7th of December, 1941 in the morning hours (in Japan, it was December 8). This military strike was a surprise attack from Japanese bombers on the U.S. Naval base in Pearl Harbor. While it was intended to prevent the U.S. fleet from interfering with Southeast Asia military actions, this attack caused America to enter the war.

The attack happened before Japan officially declared war to the U.S. Apparently Admiral Yamamoto intended originally to only start the attack 30 minutes after informing the U.S. that peace negotiations were over.

A 5,000 word notification was transmitted from Tokyo to the Japanese Embassy in two blocks, but it took too long for the Japanese ambassador to have the message transcribed and deliver it in time. U.S. code breakers had actually already deciphered most of the message several hours before the ambassador managed to deliver it.

Japan’s declaration of war was printed in the Japanese newspapers on the day of the attack already, while the U.S. only got it the next day.

 

Time of Attack

The first wave of attack were felt at 7:48 A.M. Hawaiian Time and the attack only lasted about two hours. Six aircraft carriers were used to launch a total of 353 Japanese bombers, fighter and torpedo planes and they sunk four U.S. battleships, while damaging all eight of them.  Over 2,000 Americans died in the attack and over 1,000 others were wounded.

America’s First Reactions to the Attack

(See main article: America’s First Reaction to the Attack)

December 7, 1941, arrived as a quiet Sunday morning on the West Coast. It didn’t stay that way for long. In the early afternoon, in Washington, D.C., Secretary of the Navy Frank Knox told President Franklin Roosevelt that a message from Hawaii had reached the Mare Island Naval Shipyard north of San Francisco. It read: “Air Raid Pearl Harbor. This is no drill.” The message had arrived at 10:58 a.m. Cali- fornia time, 7:58 a.m. Hawaii time.

Knox told Roosevelt that the attack was in progress even as they spoke.

Secretary of State Cordell Hull was scheduled to meet that afternoon with Japanese ambassador Admiral Kichisaburo Nomura and special envoy Saburo Kurusu to discuss the American trade boycott of Japan. Roosevelt phoned Hull and told him to say nothing to the Japanese diplomats.

The president next called his press secretary, Steve Early, and told him to issue a statement to the wire services, and Early got the Associated Press, United Press, and the International News Service on a three-way call. At 2:22 p.m. Eastern Time, the first bulletins went out, reading “Washington—White House Announces Japanese Wave Attacked Pearl Harbor.” Within minutes, the radio networks were interrupting their regular broadcasts with the news.

The NBC Blue Network got the story in its most graphic form. A reporter with KGU, the NBC affiliate in Honolulu, had gone up to the roof of the Honolulu Advertiser Building with microphone in hand and telephone in the other and had called NBC with the first eyewitness account to reach the mainland. “This battle has been going on for nearly three hours…. It’s no joke, it’s a real war.”

By now, and over the course of the coming hours, additional bulletins flooded in, telling of the simultaneous Japanese air strikes against the Philippines and Thailand. Both Hong Kong and Wake Island were also under attack.

“Japanese parachute troops are reported in Honolulu,” CBS reported. “They have been sighted off Harbor Point. At least five persons have been reported killed in the city of Honolulu. The Japanese dive bombers have been making continuous attacks, apparently from a Japanese aircraft carrier. A naval engagement is reported in progress off Honolulu. And there’s one report that a Japanese warship is bombarding the harbor. Aerial dogfights are raging in the skies over Honolulu itself.”

At 4:10 p.m., the Jack Benny Program on NBC Red was interrupted on California affiliates with news of civilians reporting for volunteer duty, and to issue a warning about avoiding “hysteria.”

Many of the 9.7 million people of the Pacific Coast States wondered what they should be doing. The immediate fear was of air raids. The images from the newsreels of the London Blitz the previous year, the firestorms and devastation wrought by German bombs during the Battle of Britain, were deeply ingrained in the minds and imaginations of Americans. For those on the Pacific Coast, knowing that the Japanese had projected their airpower as far as Hawaii clearly suggested that they could reach Washington, Oregon, or California.

It was assumed that the best form of civil defense against air raids was a blackout—turning off all lights in the evening so as not to aid enemy bombardiers in identifying cities, bridges and other targets. Throughout the West, lights were ordered to be turned off at 11:00 p.m. Likewise, civilian radio stations went off the air, because aircraft could use radio waves to locate cities, though most people did not realize that this was why the radio was suddenly silent on the night of December 7. It was unnerving. It was scary.

At 6:56 p.m., the sky was already getting dark in Seattle when radio station KIRO, announced that “in the states of Oregon, Washington, and California…every farm house, every light of any kind in that area must be out by eleven o’clock. To test your blackout, you will have plenty of time between the hours of seven and eleven…to make arrangements to get heavy black paper to seal your windows, or heavy drapes or some- thing. . . . No lights are to be used on automobiles and no lights whatever are to be shown anywhere on the Pacific coast in the states of Oregon, Washington, and California until thirty minutes after daylight.”

As the sun rose on Monday morning, those in urban areas well knew that it had been an imperfect blackout. Many had not gotten the word that there would be a blackout and large sections of downtown areas, with their lighted neon signs, had remained bathed in their usual glow. In San Francisco, master switches plunged neighborhoods into darkness while Market Street blazed brightly. William Harrelson, the general manager of the Golden Gate Bridge District, ordered his bridge into darkness shortly after 6:00 p.m., but he turned the lights back on an hour later to prevent automobile accidents.

In the San Fernando Valley north of Los Angeles, the Lockheed Aircraft factories, including the air terminal in Burbank went dark, but they were merely patches of darkness in a twinkling sea. In many places, streetlights were on individual timers and had to be turned off individually. There had been no prior planning to get this job done, and it was still not completed by morning.

Civil Defense volunteers swung into action, but most people were simply confused by the well-intentioned air raid wardens. The Associated Press reported that a woman in San Francisco phoned the police to report “a crazy man prowling about my place shouting ‘Lights out.’”

In the composing rooms of the newspapers, typographers reached for the largest fonts they had to set the headlines that screamed “WAR,” and readers stripped the newsstands as soon as the morning papers appeared.

“Japan has asked for it,” read the editorial in the Los Angeles Times. “Now she is going to get it. It was the act of a mad dog, a gangster’s parody of every principle of international honor.”

 

America’s Search for Scapegoats

(See main article: America’s Search for Scapegoats After the Attack)

When the news about Pearl Harbor reached Washington, President Roosevelt was thunderstruck—not because he was surprised by the attack itself, but because the attack had been far more dreadful than anything the administration had expected.

Faced with losses and humiliations they had not anticipated when they dictated unacceptable conditions to a proud but threatened nation—now enraged and filled with ferocious self-confidence—Roosevelt and the men around him began a frantic search for scapegoats.

Their first target was Admiral Husband Kimmel. As his predecessor Richardson had done, Kimmel had warned the president about the Navy’s lack of preparation for war. Roosevelt, however, did not warn Kimmel about the impending attack—not even after he had read the decoded Japanese message on December 6. Ten days after the attack, Kimmel and General Walter Short were both demoted and replaced.

Kimmel saw it coming. As he watched the last phase of the attack on the morning of December 7, a spent .50-caliber slug from one of his fleet’s own antiaircraft machine guns hit Kimmel in the chest, shredded his white linen uniform, and tumbled to the ground at his feet. Kimmel stooped over, picked up the half-inch-wide bullet, and looked at it glumly: “It would have been merciful had it killed me.”

General Short took his demotion humbly. Kimmel—whom Roosevelt had appointed because he was a scrapper—fought for the rest of his life to win exoneration. “The Pacific Fleet deserved a fighting chance,” Kimmel wrote in Admiral Kimmel’s Story, published in 1954. “Had we had as much as two hours of warning a full alert of planes and guns would have greatly reduced the damage. We could possibly have been able to locate the Jap carriers, and our own carriers Lexington and Enterprise already at sea to the westward of Oahu might have been brought into the picture instead of expending their efforts to the southward as a result of faulty information. The great intangible, the element of surprise, would have been denied the Japs.”

The question whether Kimmel was substantially to blame for a lack of vigilance remains open. But why didn’t the White House or the War Department telephone Hawaii when the president read a decoded message that said, “This means war”? That question is unanswered by anything Kimmel did or did not do.

Pearl Harbor had been an obvious target—so obvious, in fact, that John Huston was at work at the time on a movie about a fictional Japanese air attack. After the attack, Huston scurried to change the target in the film from Pearl Harbor to the Panama Canal. The film kept its original title, Across the Pacific, perhaps because it was almost completed when the Japanese struck. Had the film been released before the attack, Roosevelt’s embarrassment might have been even deeper than it was.

Three days after the attack, Henry Morgenthau Jr. asked J. Edgar Hoover what he thought about rounding up the entire Japanese and Japanese-American population of the west coast. Hoover was appalled and bluntly told Morgenthau that Attorney General Francis Biddle would not approve any “dragnet or round-up procedure.” Many of these ethnic Japanese were American citizens, Hoover reminded Morgenthau, and such an action would be illegal. He also knew that such a move was unnecessary. Based on information from loyal Japanese-Americans, including Togo Tanaka, and from Korean dissidents, including Kilsoo Haan, as well as information obtained by burglarizing the Japanese consulate in Los Angeles and the Black Dragon Society’s office, Hoover had a comprehensive list of people he wanted to arrest, and he had already started.

On March 18, 1942, Roosevelt signed Executive Order 9102, establishing the War Relocation Authority, which Senator Robert Taft called the sloppiest criminal law he had ever heard of. Japanese-Americans born and raised in the United States, many of them Christians, many of them graduates of American high schools and colleges, were moved on a few days’ notice to ten concentration camps in isolated mountain and desert locations. Some collapsed of heat stroke before they arrived at the hastily constructed tar-paper and clapboard barracks, where multiple families shared a single room.

By June 7, 112,000 American men, women, and children were interned behind barbed wire, eating wretched food in harsh climates.

Operation Snow—Was Foreign Espionage Responsible for the Attack?

(See main article: Operation Snow)

Historians have long discussed whether foreign espionage was responsible for Japan’s military attack on Pearl Harbor. But new research has connected major pieces of that Soviet activity within the United States in much detail. And most of it leads to one man.

Much of the evidence points to one American government worked-turned-spy: Harry Dexter White. He was the top official in FDR’s Treasury Department and had the ear of prominent New Dealers such as his boss Secretary Henry Morgenthau, as well as others in President Roosevelt’s Cabinet.

White was in close contact with Vitaly Pavlov, the “second-in-command” in the NKVD (predecessor to the KGB). The two plotted a strategy—”Operation Snow”—that initiated a toppling of dominoes that utlimately led to December 7, 1941. The main issue was oil. Japan didn’t have any and had to acquire it from the Soviet Union or the United States. White worked furiously to pull levels of American government power to provoke an attack from Japan, sparing the Soviets.

He did so by  influencing the Roosevelt administration against reaching a diplomatic deal with the Japanese. White worked overtime once the Hitler-Stalin pact abruptly ended, since a Japanese attack on Russia would divert Russia’s forces away from its Western Front, making Germany’s conquest of the Soviet Union all the more likely.

Much of what we know about White comes from his August 1948 testimony before the House Committee on Un-American Activities. But because the former Treasury official failed to exonerate himself in these committee appearance, he took his own life three days later in a disguised suicide

 

Other Articles

U.S.-Japanese Diplomatic Attempts to Divert War Before the Attack

Soviet Mole Harry White’s Efforts to Trigger the P.H. Attack

7 Things You Didn’t Know About P.H.

The Meeting of the Spy Masterminds Who Triggered P.H.

Russian and Japanese Conflict in the Lead-Up to P.H

Dusko Popov: The Triple-Agent, Real-Life James Bond Who Warned the U.S. About P.H.