On the morning of Sunday, December 7, 1941, the Imperial Japanese Navy launched a surprise air attack on the U.S. naval base at Pearl Harbor, Hawaii. In less than two hours, 353 Japanese aircraft struck the Pacific Fleet at anchor, killing 2,403 Americans and destroying or damaging 21 U.S. ships. The attack ended American neutrality in a single morning and drew the United States fully into World War II.
The story starts with an oil embargo that cornered Japan, a naval plan drawn up by an admiral who had studied in America, and a strike force that sailed 3,400 miles across the Pacific in total silence. Here is what happened, ship by ship and hour by hour, and why it still matters.
Key Highlights
- On December 7, 1941, Japan launched a surprise air attack on Pearl Harbor, Hawaii, killing 2,403 Americans and wounding 1,178.
- 353 Japanese aircraft attacked in two waves, launched from six aircraft carriers about 230 miles north of Oahu.
- The battleship USS Arizona exploded at about 8:10 a.m., killing 1,177 of her crew, nearly half of all American deaths that day.
- Five Japanese midget submarines also tried to enter the harbor; the USS Ward sank one of them at 6:45 a.m., the first American shot of the Pacific War.
- The next day, President Franklin D. Roosevelt asked Congress for a declaration of war, calling December 7 “a date which will live in infamy,” and the United States entered World War II.
The Road to War
Japan did not attack Pearl Harbor on a whim. The strike grew out of years of rising tension between Washington and Tokyo, and of a Japanese war plan that required knocking the U.S. Pacific Fleet out of action first.
The oil embargo and the Hull Note
Japan had been at war in China since 1937 and was desperate for the raw materials to keep fighting. When Japanese troops moved into French Indochina in 1940 and 1941, the United States answered with sanctions that became a total oil embargo in July 1941: Japan imported most of its oil, and its navy would run dry within a couple of years without it.
Months of negotiations followed. On November 26, 1941, Secretary of State Cordell Hull handed Japan a ten-point statement demanding Japanese withdrawal from China and Indochina. Tokyo treated the Hull Note as an ultimatum. That same day, the Japanese strike force was already at sea.
Yamamoto’s plan for a preemptive strike
Admiral Isoroku Yamamoto, commander of Japan’s Combined Fleet, devised the plan. He had studied at Harvard and served as Japan’s naval attache in Washington, so he understood American industrial power better than most of his colleagues. His reasoning was blunt: if Japan was going to seize the oil-rich Dutch East Indies and Britain’s Southeast Asian colonies, the U.S. Pacific Fleet had to be crippled first.
He chose a Sunday morning, when the fleet would likely be in port and readiness at its lowest. His own warning to Japan’s leadership would prove prophetic: he could run wild for six months, he said, but after that he had no expectation of success.
The Japanese Strike Force
The force that sailed for Hawaii was the most powerful naval striking arm ever assembled to that point. Vice Admiral Chuichi Nagumo led six fleet carriers: the Akagi, Kaga, Soryu, Hiryu, Shokaku, and Zuikaku. Of the 414 aircraft aboard, 353 would fly in the raid.
The task force left Hitokappu Bay in the Kurile Islands on November 26, 1941, and crossed about 3,400 miles of empty North Pacific under strict radio silence. On the morning of December 7, the carriers turned into the wind roughly 230 miles north of Oahu and began launching aircraft. Japanese planners called the operation the Hawaii Operation, or Operation Z.
The First Wave
At about 6:00 a.m. Hawaiian time, the first wave of 183 aircraft lifted off under Commander Mitsuo Fuchida: Kate torpedo bombers for the battleships, Val dive bombers for the airfields, and Zero fighters for strafing and cover.
Surprise was almost total, though the warning signs were there. At 3:42 a.m., the minesweeper USS Condor spotted a submarine periscope near the harbor entrance. At 7:02 a.m., an Army radar station at Opana Point picked up the incoming formation 132 miles out, but the officer on duty assumed the blip was a flight of B-17 bombers expected from California and told the operators not to worry about it.
At 7:49 a.m., Fuchida broke radio silence with the coded message “Tora! Tora! Tora!” It meant surprise had been achieved. Moments later the first bombs fell on Wheeler Field, Hickam Field, and Ford Island, and the first torpedoes ran toward Battleship Row. The attack is officially recorded as beginning at 7:55 a.m.
The Kates of the first wave drove torpedoes into the California, Oklahoma, West Virginia, and Nevada, and dropped armor-piercing bombs on the battleships from high altitude. Val dive bombers pounded the air stations to destroy American aircraft on the ground. For about 90 minutes, the harbor burned.
The Second Wave
A second wave of about 170 aircraft struck at about 8:54 a.m., carrying lighter munitions and meeting far heavier antiaircraft fire. It worked over the shipyard, dry docks, and the burning battleships, and hit Hickam and Kaneohe airfields again.
The last Japanese aircraft departed around 9:45 a.m. A third wave had been readied, but Nagumo, uncertain of the American carriers’ location, chose to withdraw. It was a fateful call: the fuel tanks, repair yards, and submarine base were left untouched, and the American carriers were at sea and unharmed. For more ship-by-ship facts about the battle, see our Facts About Pearl Harbor guide.
Ship by Ship: What Happened on Battleship Row
All eight American battleships in the harbor that morning were damaged. Here is what happened to each.
USS Arizona (BB-39)
At about 8:10 a.m., a 1,760-pound armor-piercing bomb detonated Arizona’s forward ammunition magazine. She sank in less than nine minutes with 1,177 of her crew, nearly half of all Americans killed that day. Arizona was the only battleship never raised. Today the USS Arizona Memorial spans her sunken hull, where more than 900 crewmen remain entombed.
USS Oklahoma (BB-37)
Oklahoma took several torpedoes in rapid succession and capsized, trapping more than 400 men inside. Rescue crews worked through the night cutting into her overturned hull; 32 men were pulled out alive. She lost 429 of her crew, was eventually raised, and was lost at sea under tow in 1947 on her way to be scrapped.
USS West Virginia (BB-48)
Hit by at least seven torpedoes and two bombs, West Virginia settled upright into the mud beside the Tennessee. Quick counter-flooding kept her from capsizing. She lost 106 men, was raised and rebuilt, and returned to the fleet in July 1944.
USS California (BB-44)
California, the fleet flagship, took two torpedo hits and settled slowly into the harbor mud over the following days. She lost 100 of her crew. Raised and modernized, she returned to service in May 1944 and shelled Japanese shore defenses at Saipan, Guam, and Leyte.
USS Nevada (BB-36)
Nevada was the only battleship to get underway that morning, and Japanese pilots concentrated on sinking her in the channel. After taking torpedo and bomb hits, her captain deliberately beached her to keep the entrance clear. She lost 60 men, was raised, and returned to the fleet in December 1942, later providing shore bombardment at Normandy on D-Day, at Iwo Jima, and at Okinawa.
USS Maryland, USS Tennessee, and USS Pennsylvania
The remaining three battleships were damaged but repaired quickly. Maryland, sheltered from torpedoes by Oklahoma, was back by February 1942. Tennessee, pinned against the burning West Virginia, lost five men and returned in March 1942. Pennsylvania, in dry dock with two destroyers, lost nine men and was back the same month. Our full list of people who died at Pearl Harbor honors the crews of every ship.
The Midget Submarines
The air attack was not the only threat that morning. Japan also sent five two-man Type A midget submarines to slip into the harbor and torpedo ships during the raid.
Long before the first plane appeared, the destroyer USS Ward encountered one of the midget subs near the harbor entrance. At 6:45 a.m., more than an hour before the air attack began, the Ward opened fire and sank it, the first American shot of the Pacific War. The report climbed the chain of command too slowly to make a difference.
A second midget submarine got inside the harbor and was rammed and sunk by the destroyer USS Monaghan around 8:30 a.m. The most famous of the five was HA-19: its gyrocompass failed, it ran aground, and its crewman, Ensign Kazuo Sakamaki, washed ashore to become America’s first prisoner of war of World War II. For the full underwater story, read The Attack on Pearl Harbor: The Submarine Perspective.
The American Response That Morning
Although the attack was a complete surprise, plenty of Americans fought back. Antiaircraft guns were manned within minutes, and Army Air Corps pilots got a handful of fighters airborne.
Doris “Dorie” Miller, a mess attendant aboard the West Virginia, carried his wounded captain to safety and then manned a .50-caliber antiaircraft gun until he ran out of ammunition. He received the Navy Cross in May 1942. Rear Admiral Isaac Kidd and Captain Franklin Van Valkenburgh, both aboard the Arizona, stayed at their posts and were killed; both received the Medal of Honor posthumously.
Meanwhile, the three U.S. aircraft carriers were nowhere near the harbor: the Enterprise was returning from Wake Island, the Lexington was ferrying planes to Midway, and the Saratoga was on the West Coast. Their absence, pure luck of scheduling, preserved the core of American naval air power in the Pacific.
FDR and the Declaration of War
The news reached President Franklin D. Roosevelt that afternoon in Washington, and that evening he called an emergency cabinet meeting. At noon on December 8, he addressed a joint session of Congress.
“Yesterday, December 7, 1941, a date which will live in infamy, the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan,” he said. Congress declared war on Japan the same day. On December 11, Germany and Italy declared war on the United States, and Congress returned the favor, bringing America into the war on both fronts.
Why It Was a Turning Point
Pearl Harbor was a Japanese tactical victory that became a strategic disaster. Japan sank or damaged 21 American ships and destroyed 188 aircraft at the cost of 29 planes and five midget submarines. But it failed in every way that mattered.
First, the aircraft carriers survived. Pacific naval warfare would be decided by carrier air power, and six months later at Midway, those surviving carriers broke the back of the Japanese navy. Second, the fuel tanks, repair yards, and dry docks were untouched, so damaged ships could be raised and repaired and the base kept operating. Six of the eight battleships hit at Pearl Harbor eventually returned to service.
Most importantly, the attack ended American isolationism in a single morning. Before December 7, most Americans wanted nothing to do with the war in Europe or Asia. After it, the nation mobilized with a unity and industrial might that Japan’s planners had badly underestimated, and the Pacific War that began at Pearl Harbor ended with Japan’s surrender in August 1945.
Visiting the Sites Today
Pearl Harbor is now the Pearl Harbor National Memorial, administered by the National Park Service. The USS Arizona Memorial program includes a boat ride to the memorial spanning the sunken battleship, where oil still rises slowly from the wreck.
Nearby, the Battleship Missouri Memorial is moored at Ford Island, just off the Arizona’s resting place. The pairing is deliberate: the Missouri is where Japan formally surrendered on September 2, 1945, so the two ships bookend the Pacific War, one marking its beginning and the other its end.
If you are planning a visit, our Ultimate Guide to Visiting Pearl Harbor covers tickets, the free Arizona Memorial program, and how to fit the museums and the Missouri into one day.
Frequently Asked Questions
How many people died at Pearl Harbor?
A total of 2,403 Americans were killed in the attack, and 1,178 were wounded. The toll included 2,335 servicemen and 68 civilians. Nearly half of the dead, 1,177 sailors and Marines, were aboard the battleship USS Arizona, which exploded after a bomb detonated her forward ammunition magazine.
How many Japanese planes attacked Pearl Harbor?
353 Japanese aircraft attacked Pearl Harbor in two waves, launched from six aircraft carriers about 230 miles north of Oahu. The first wave of 183 aircraft struck at about 7:55 a.m., and a second wave of about 170 aircraft followed at about 8:54 a.m. The Japanese lost 29 aircraft during the raid.
Why did Japan attack Pearl Harbor?
Japan attacked Pearl Harbor as a preventive strike to cripple the U.S. Pacific Fleet before it could interfere with Japan’s planned conquest of Southeast Asia. The immediate trigger was the American oil embargo of July 1941, which threatened to starve Japan’s navy of fuel. Japanese leaders believed a surprise blow would buy them time to seize the resource-rich Dutch East Indies and British colonies unopposed.
What happened to the ships sunk at Pearl Harbor?
Of the eight battleships damaged at Pearl Harbor, six eventually returned to service. The California, West Virginia, and Nevada were raised and rebuilt, while the Maryland, Tennessee, and Pennsylvania were repaired. Only the Arizona and Oklahoma never returned: the Arizona remains where she sank as a memorial, and the Oklahoma was lost at sea under tow in 1947.
What was the USS Ward’s role in the attack?
The destroyer USS Ward fired the first American shots of the Pacific War. At 6:45 a.m. on December 7, more than an hour before the first Japanese plane arrived, the Ward spotted a Japanese midget submarine near the harbor entrance, opened fire, and sank it with depth charges. Her report of the contact reached higher command too slowly to raise the alarm.
Why was Pearl Harbor a turning point in history?
Pearl Harbor ended American isolationism overnight and brought the United States into World War II. Although the attack was a Japanese tactical victory, it failed strategically: the American aircraft carriers were at sea and unharmed, and the harbor’s fuel tanks and repair facilities were left intact. Within four years, the mobilized industrial power of the United States had defeated Japan, Germany, and Italy.