Attack on Pearl Harbor

Attack on Pearl Harbor

On December 7, 1941, the Empire of Japan launched a surprise military strike on the United States Pacific Fleet at its naval base at Pearl Harbor on Oahu, Hawaii. At the time, the U.S. was a neutral country in World War II. The attack was carried out by planes from Japanese aircraft carriers, catching the United States completely by surprise.

The strike led the U.S. to declare war on Japan the next day, drawing the country into World War II. This event changed the course of history and brought the United States into the fight against the Axis powers. The attack on Pearl Harbor remains one of the most significant events in both American and world history.

The Japanese planned the attack carefully, hoping to weaken the U.S. Navy. Over two waves of bombers and fighters struck the naval base, damaging or sinking many ships and destroying hundreds of aircraft. The attack caused great loss of life and became a turning point that led to the United States fully engaging in the war.

Background

Main article: Prelude to the attack on Pearl Harbor

War between the Empire of Japan and the United States had been a worry since the 1920s. Japan was concerned about America growing closer to its areas, like Hawaii and the Philippines. Japan also needed resources such as oil to support its military, especially after moving into China.

Tensions grew when Japan moved into parts of French Indochina in 1940. The United States responded by stopping some trade with Japan, including sending airplanes and machine tools. However, the U.S. still sent oil, which Japan needed. In 1941, the U.S. stopped sending oil after Japan took more land in Indochina. This led Japan to plan taking oil from places like the Dutch East Indies. Both countries tried to talk, but they could not agree. Japan wanted the U.S. to lift its trade limits, while the U.S. wanted Japan to leave China. These failed talks set the stage for what happened next.

Diplomacy

War between the Empire of Japan and the United States was seen as possible since the 1920s. Japan was careful of America’s growth near its areas, such as Hawaii and the Philippines, which were close to Japan's influence.

Japan believed it needed resources to support its military. This included items like iron and oil that it could not get enough of at home.

Although Japan had been unfriendly toward the United States after opposing the Racial Equality Proposal, they remained trading partners. Tensions grew more after Japan's move into Manchuria in 1931. Over the next years, Japan moved into China, starting the Second Sino-Japanese War in 1937. Japan tried to control China and get resources to win there. The “Southern Operation” was planned to help these efforts. Still, Japan depended on U.S. oil, even for forces in Japan-occupied Manchuria. In a memo from October 24, 1934, Stanley K. Hornbeck wrote about a meeting with Standard Oil New Jersey head Walter C. Teagle and President Franklin D. Roosevelt. The memo said Teagle was not helpful to U.S. requests and that Standard Oil got special treatment from Japan, making the company less controlled by Japan’s business rules. Hornbeck noted that because of Teagle’s deals with Japan, “most of the oil and oil products imported into Japan came from America.”

Starting in December 1937, events like the Japanese attack on USS Panay, the Allison incident, and the Nanking Massacre made people in the West oppose Japan more. The United States tried to work with the United Kingdom to stop Japan, but it did not work. In 1938, after a request by President Roosevelt, American companies stopped selling things for war to Japan.

In 1940, Japan moved into French Indochina, trying to stop supplies from reaching China. The United States stopped sending airplanes, parts, machine tools, and aviation gasoline to Japan, which Japan saw as unfriendly. The United States did not stop oil, partly because many in Washington thought Japan depended on American oil and would not risk stopping it.

In mid-1940, President Franklin D. Roosevelt moved the Pacific Fleet from San Diego to Hawaii. He also ordered more military forces to the Philippines, hoping to stop Japanese moves in the Far East. The Japanese leaders thought that any attack on the United Kingdom's Southeast Asian colonies, like Singapore, would bring the United States into the war, so they planned a big attack to stop American ships from helping. An invasion of the Philippines was also planned. The American War Plan Orange had plans to defend the Philippines with 40,000 men, but this was not done because Douglas MacArthur thought they would need ten times that many. By 1941, American leaders thought they might have to leave the Philippines if war started. That year, Admiral Thomas C. Hart, leader of the United States Asiatic Fleet, was told to prepare for that.

The United States finally stopped sending oil to Japan in July 1941, after Japan took more of French Indochina following the Fall of France. Because of this, Japan planned to take the oil-rich Dutch East Indies. On August 17, Roosevelt warned Japan that America would act if “neighboring countries” were attacked.

Japan and the United States talked during 1941 to try to improve their relationship. Japan said it would leave most of China and Indochina after making peace with the Nationalist government. It also offered to interpret the Tripartite Pact in its own way and not treat other countries unfairly, if others did the same. Washington turned down these ideas. Japanese Prime Minister Konoe then offered to meet with Roosevelt, but Roosevelt said they needed an agreement first. The American ambassador in Japan kept asking Roosevelt to accept the meeting, saying it was the only way to keep Konoe’s government and peace in the Pacific. But nothing happened. The Konoe government fell the next month when the Japanese military refused to pull all troops out of China.

Japan’s last offer, given on November 20, said Japan would leave southern Indochina and not attack in Southeast Asia, if the United States, United Kingdom, and Netherlands gave one million U.S. gallons of fuel, ended their limits on Japan, and stopped helping China. The American answer on November 26 required Japan to leave China completely and make non-aggression agreements with Pacific countries. On November 26 in Japan, the day before this answer arrived, the Japanese task force left for Pearl Harbor.

The Japanese planned the attack to stop the United States Pacific Fleet from getting in the way of their military moves in Southeast Asia against lands owned by the United Kingdom, the Netherlands, and the United States. From Japan’s view, it was a strike “before the oil ran out.”

Military planning

Planning for an attack on Pearl Harbor began in early 1941 under Admiral Isoroku Yamamoto, who led Japan’s Combined Fleet. He got approval for formal planning and training after much discussion with Naval Headquarters, including threatening to leave his position. Full planning started in early spring 1941, mainly by Rear Admiral Ryūnosuke Kusaka, with help from Commander Minoru Genda and Yamamoto’s Deputy Chief of Staff, Captain Kameto Kuroshima. The planners closely studied the 1940 British air attack on the Italian fleet at Taranto.

Over the next months, pilots trained, equipment was changed, and information was gathered. Even with these steps, Emperor Hirohito did not approve the attack plan until November 5, after the third of four Imperial Conferences to discuss it. At first, he was not sure about going to war but finally allowed the Pearl Harbor attack even though some advisors disagreed. Final approval came from the emperor on December 1, after most Japanese leaders told him the Hull note would “ruin the results of the China incident, danger Manchukuo and weaken Japan’s control of Korea.” Before the attack, he got more involved in military matters, even joining the Conference of Military Councillors, which was unusual for him. He also asked for more information about the war plans. An aide said he showed happiness when he heard about the success of the surprise attacks.

By late 1941, many people thought war between the United States and Japan was coming. A Gallup poll just before the attack found that 52% of Americans thought war with Japan would happen, 27% did not, and 21% had no opinion. While American Pacific bases had often been on alert, leaders did not think Pearl Harbor would be the first target; they thought the Philippines would be attacked first. This was because of the air bases and naval base at Manila, which could affect sea routes and supplies to Japan. They also wrongly thought Japan could not do more than one big naval operation at a time.

Objectives

The Japanese attack had several main goals. First, it wanted to destroy important American ships to stop the Pacific Fleet from getting in the way of Japan’s plans to take the Dutch East Indies and Malaya and to let Japan control Southeast Asia without help. The leaders of the Imperial Japanese Navy followed Alfred Thayer Mahan’s “decisive battle” idea, especially destroying as many battleships as possible. Second, it hoped to give Japan time to strengthen its position and navy before new American ships from the 1940 Vinson-Walsh Act could change the chance of winning. Third, to hurt America’s ability to gather forces in the Pacific, battleships were the main targets because they were important symbols for navies at the time. Finally, they hoped the attack would lower America’s spirit so much that the American government would drop its demands and seek peace.

Attacking the Pacific Fleet at Pearl Harbor had two big problems: the ships would be in very shallow water, so they could be lifted out and possibly fixed, and most sailors would survive since many were on shore leave or would be saved from the harbor. Another problem was that all three Pacific Fleet aircraft carriers (Enterprise, Lexington, and Saratoga) were not there. Even with these worries, Yamamoto decided to go ahead.

Japan felt sure it could win a short war, so other places in the harbor, like the navy yard, oil stores, and submarine base, were not attacked because they thought the war would end before these could matter.

Approach and attack

On November 26, 1941, a Japanese group of six aircraft carriers left from Hittokapu Bay on Etorofu Island in the Kuril Islands. They headed toward a spot northwest of Hawaii. The plan was to launch 408 aircraft to attack Pearl Harbor. This included 360 planes for two attack waves and 48 for defensive combat air patrol.

The first wave planned to attack battleships and aircraft carriers. The second wave would target carriers and cruisers, and then battleships if needed. The attack began before Japan had officially declared war. This caused confusion and delayed messages. The first wave included bombers with special torpedoes for shallow water and dive bombers for ground targets. Fighters were meant to destroy parked aircraft to stop interference.

The attack surprised the United States Pacific Fleet. Even though there were warnings, American defenses were not ready. Many aircraft were parked close together, and guns had no one operating them. The attack caused big losses for the United States, including the sinking of several battleships and the destruction of many aircraft. The Japanese lost fewer planes but met more resistance from American anti-aircraft fire in the second wave. Not launching a third wave to attack shore buildings was later thought to be a missed chance, as destroying them could have delayed American actions in the Pacific.

Ships lost or damaged

Further information: List of United States Navy ships present at Pearl Harbor, December 7, 1941

Twenty-one American ships were damaged or lost during the attack on Pearl Harbor. Most of these ships were repaired and used again later. Five battleships were fixed and helped the United States fight against Japan.

Battleships

• Arizona: hit by bombs, exploded, and could not be saved.
• Oklahoma: hit by torpedoes, turned over, and could not be saved.
• West Virginia: sunk but was fixed and returned to service in 1944.
• California: sunk but was fixed and returned to service in 1944.
• Nevada: damaged but was fixed and returned to service in 1942.
• Pennsylvania: damaged while in a dry dock but stayed in service.
• Tennessee: damaged but returned to service in 1942.
• Maryland: damaged but returned to service in 1942.

Ex-battleship (target/AA training ship)

• Utah: hit by torpedoes, turned over, and could not be saved.

Cruisers

• Helena: hit by a torpedo but returned to service in 1942.
• Raleigh: hit by a torpedo but returned to service in 1942.
• Honolulu: had light damage but stayed in service.

Destroyers

• Cassin: damaged in a dry dock but was fixed and returned to service in 1944.
• Downes: damaged in a dry dock but was fixed and returned to service in 1943.
• Helm: damaged but kept patrolling and returned to service in 1942.
• Shaw: hit by bombs but returned to service in 1942.

Auxiliaries

• Oglala: damaged and turned over but returned to service in 1944.
• Vestal: damaged but returned to service by 1942.
• Curtiss: damaged but returned to service in 1942.
• Sotoyomo: damaged and sunk but returned to service in 1942.
• YFD-2: damaged and sunk but returned to service in 1942.

Salvage

Captain Homer N. Wallin led a formal salvage operation to fix ships after the attack. Divers worked on the damaged ships, patching holes and removing water. Within six months, five battleships and two cruisers were repaired well enough to move for more fixes.

Salvage work went on for another year. The ships Arizona and Utah were too damaged to save and stayed where they sank. The Oklahoma was lifted out of the water but later tipped over while being moved. The Nevada was hard to repair, and some workers got sick from bad air inside the ship. Parts from damaged ships were used to make the harbor safer.

News coverage

Coverage in the United States

When the attack on Pearl Harbor began, the White House Press Secretary, Stephen Early, announced that Japan had attacked Pearl Harbor and other military sites on the island of Oahu. News programs on radio stations like CBS and NBC quickly shared the news with listeners, stopping regular shows to tell people what was happening.

Only a few thousand television sets existed at the time, and most were in cities like New York, Chicago, Los Angeles, and Philadelphia. The attack was shown on a few TV stations, but no recordings of these broadcasts exist today.

Coverage in Japan

In Japan, news of the attack was announced on the radio in the morning, stating that Japan was now at war with the United States and Britain. Newspapers in Japan reported the attack, but the government decided what could be reported. One major newspaper, The Asahi Shimbun, shared the news and agreed with the government’s choices.

Coverage elsewhere

The British Broadcasting Corporation (BBC) in the United Kingdom reported the attack and also said that Manila in the Philippines was also under attack.

Aftermath

Main articles: Consequences of the attack on Pearl Harbor and Day of Infamy speech

The day after the attack, U.S. President Franklin D. Roosevelt gave a speech to Congress, asking for war against Japan. Congress agreed quickly. Soon after, Germany and Italy also declared war on the United States.

The attack surprised many countries that were friends of the United States. Japan attacked other places soon after, and more battles happened. The event changed World War II and brought the United States into the fight.

The attack caused big changes, like new ways for armies to work and some people being treated unfairly. Many people were honored for being brave during the attack.