The US asked Japan to leave China less than two weeks before Pearl Harbor

Hitler declared war on the United States four days after Pearl Harbor

Despite having no treaty obligation to join Japan’s fight, Hitler declared war on the US on Dec. 11, 1941. The move pulled America into the European theater and is widely seen as one of Hitler’s most strategic blunders.

Japan’s imperial expansion in Asia set the stage for war with the US

Between 1931 and 1941, Japan seized Manchuria, launched a full-scale war in China and occupied French Indochina, moves that intensified its demand for strategic resources and triggered escalating US-led embargoes—particularly the 1941 oil cutoff—which sharply raised the risk of war between the two countries.

Before World War II, the US was a Pacific power

Decades before Pearl Harbor, the US held major Pacific territories—Hawaii, the Philippines, Guam, American Samoa, and numerous island bases—giving it strategic reach across the western Pacific. This presence increasingly overlapped with Japan’s imperial ambitions in the region, contributing to rising tensions.

Japan attacked Pearl Harbor largely because it was running out of oil

This video traces how US-led sanctions and Japan’s near-total dependence on imported oil pushed Japanese leaders toward a high-risk plan: seize Southeast Asian oil fields and neutralize the American Pacific Fleet, hoping Washington would negotiate rather than fight.

Before Pearl Harbor, the US was a nonbelligerent ally to the Allied powers

Between September 1940 and December 7, 1941, the United States remained officially neutral—yet President Roosevelt incrementally shifted policy from “cash‑and‑carry” to Lend‑Lease, funneling critical military aid to Britain and other allies without entering the war.

The US Pacific strategy sought control of key islands to close in on Japan

The US adopted a two-pronged "island hopping" campaign across the Central and Southwest Pacific from 1943–44, deliberately targeting strategically crucial but less-defended islands. This allowed forces to bypass heavily fortified Japanese strongholds and build airfields for bombers aimed at Japan, drastically accelerating the path toward Tokyo while conserving manpower and resources.

What happened to Americans who were in Japan during Pearl Harbor?

When Japan bombed Pearl Harbor in December 1941, roughly 10,000 American civilians were stranded in Japanese-occupied territory. Tense diplomatic negotiations eventually secured two prisoner exchanges conducted via ship across 20,000 nautical miles to return nearly 3,000 Allied civilians, while Japanese Americans in North and South America were sent in the opposite direction, many to a country they had never called home.

The attack at Pearl Harbor required nearly a year of planning and preparation

In early 1941, Admiral Isoroku Yamamoto ordered detailed planning for a surprise carrier strike on Pearl Harbor. Japanese teams spent months refining torpedo modifications, training pilots, and rehearsing the complex attack.

US intelligence failures contributed to the success of the Japanese attack

Despite breaking Japan’s diplomatic codes, US agencies failed to integrate warnings, successfully track Japan’s carriers, or even believe a Hawaii strike was possible (they also had not cracked Japan’s naval codes). Missed signals, ignored reports and poor coordination led to one of the worst intelligence failures in US history.

Roosevelt’s post-Pearl Harbor address became one of America’s most iconic speeches

Delivered to a joint session of Congress on Dec. 8, 1941, President Franklin D. Roosevelt declared Dec. 7 “a date which will live in infamy.” The speech, heard by tens of millions of Americans, helped consolidate national support for entering the war.

Okinawa’s ferocity convinced the US atomic bombs was necessary

The brutal 82-day Battle of Okinawa—where US forces suffered nearly 50,000 casualties and Japanese military and civilians lost over 200,000 lives—clinched the grim reality that a full invasion of Japan would be even bloodier. This stark lesson directly shaped American decisions to deploy atomic weapons, aiming to avoid a potentially catastrophic ground war on the Japanese mainland.

The attacks prompted a quick jump in American public support for war

In a Gallup poll taken days after the attack, an extraordinary 97% of Americans approved Congress declaring war on Japan—reflecting overwhelming national unity in the wake of the strike.

The US used military pressure to force Japan to open to foreign trade in the 1850s

Commodore Matthew Perry arrived in Edo Bay (now Tokyo Bay) with heavily armed warships, pressuring Japan to open its ports. His expeditions led to the 1854 Treaty of Kanagawa, which opened two ports for supplies and established formal US-Japan relations. Full commercial trade followed later under the 1858 Harris Treaty.

Hawaii lived under martial law for nearly three years after Pearl Harbor

After the attack, Hawaii was placed under sweeping military rule—curfews, censorship, warrantless arrests, ID papers, and mass detentions transformed everyday life. More than 2,000 people were arrested within 48 hours of the attack, and the islands remained under martial law for nearly three years.

The commander of the Japanese force at Pearl Harbor speaks on the Merv Griffin show

Mitsuo Fuchida, who led the first wave of the Pearl Harbor attack, converted to Christianity in 1950, after reading the testimony of a former American POW. He later traveled through Japan and the United States, sharing his story and working as a Christian evangelist.

Japan committed mass war crimes during its invasion of China

During the 1937 invasion, Japanese forces carried out systematic atrocities—including mass executions, rape, torture, forced labor, and chemical warfare. The Nanjing Massacre alone killed tens of thousands over a span of six weeks, with some estimates claiming 300,000.

The Flying Tigers: American fighter pilots who fought for China in WWII

Read the story of the Flying Tigers, a unit of American pilots, many Chinese-Americans, hired by the Chinese in 1941 to fight the Japanese in the skies. While the US wasn't officially at war with Japan until later on, some of the earliest American "victories" over the Japanese were won by the Flying Tigers. Read more of this amazing bit of aviation history here.

The US never formally declared war in Vietnam

Instead of formally declaring war, Congress passed the Gulf of Tonkin Resolution in 1964, granting President Johnson broad authority to use military force. The resolution became the legal basis for escalating US involvement without an official declaration of war.

The UK was already in a depression before the US Great Depression took hold

The US Great Depression was felt globally, but the severity and length of different countries’ economic downturns varied. For instance, Japan was the first country to exit its depression.

The Pacific Northwest's last 'really big one'

More than 300 years ago, a shift in the Cascadia subduction zone caused the seafloor near the Pacific Northwest coast to drop by three to six feet. The force generated a massive tsunami that traveled across the Pacific and devastated Japan.

In 1939, an industry group asked Franklin Roosevelt to move Thanksgiving

Specifically, the Retail Dry Goods Association warned Franklin Roosevelt that if the holiday season didn’t begin until after Americans celebrated Thanksgiving on the traditional final Thursday in November, retail sales would tank. In 1941 Congress passed a law that made Thanksgiving the fourth rather than the last Thursday in November.

China's 'One China' principle vs. the US 'One China' policy

The "One China" policy means different things to different people, but in the larger sense there are two primary interpretations: the Chinese and the American versions. Both refer to relations and contact between the mainland People's Republic of China and Taiwan/The Republic of China. This article covers the subtleties and differences between each country's approach to the "One China" principle.

The Kennan Telegram shaped early US Cold War strategy

In 1946, diplomat George Kennan sent a long telegram from Moscow warning that the Soviet Union was inherently expansionist. His analysis laid the groundwork for the US policy of containment that defined the early Cold War.

Prelude to the Tiananmen Square crackdown

On June 2, 1989, two days before the military-led massacre that would come to be known as the Tiananmen Square crackdown, nine of China's top leaders discussed how to stop pro-democracy protesters. During this meeting, leader Deng Xiaoping delivered a speech that has shaped the country ever since, in which he advocated for a forceful end to the protests while supporting China's economic "opening-up" featured in protesters' demands.

Take a multimedia journey through the thirteen days that nearly ended the world

In October 1962, the Cuban Missile Crisis brought the US and Soviet Union to the brink of nuclear war. This interactive archive from the JFK Library reconstructs those tense days through documents, photos, and secretly recorded conversations from the Kennedy White House.

Abraham Lincoln was almost assassinated weeks before his inauguration as he traveled from Illinois to DC through Baltimore in 1861; it took two independent claims for Lincoln to be convinced the threat was real

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

In 1915, workers recovered a submarine-like vessel from the Chicago River, prompting fears of German espionage

'Shogun,' a 1980s TV series, helped popularize sushi in the US by stimulating an American interest in Japanese culture.

The Beatles' US label rejected the band's first two singles, 'Please Please Me' and 'From Me to You,' with one executive calling the band 'dead in the water.'

In 2018, 26-year-old missionary John Allen Chau was killed by tribesmen after attempting to reach and evangelize on India's isolated North Sentinel Island

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

Watch contemporary footage covering the US-backed Shah of Iran fleeing the country in the face of the 1979 Iranian Revolution

Brandi Chastain, the star of the 1999 US victory over China in the 1999 Women's World Cup, was a last-second choice to take the penalty kick that sealed the victory.

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Meet the 56 signers of the Declaration of Independence—most of whom didn't put pen to paper until August 2, 1776—and see their original signatures.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

Mark Twain spent decades feuding with the US Postal Service, convinced its costs and regulations were bureaucratic overreach.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

Poison ivy's characteristic rash is caused by an allergic response to an oily compound in the plant called urushiol.

A Yale student wrote a profound essay about the consulting industry's influence on elite college students that was published in a book of her writing after she died in a post-graduation car accident.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Dorothy's famous entrance into Oz in 'The Wizard of Oz' relied on analog tricks, including a body double and sepia-toned paint, as much as it did on technology

Explore chaos in this simulation of two double pendulums, where small differences in the release angles produce wildly different outcomes.

See this overview of the firework rules across all 50 states, ranging from a complete ban on non-professional fireworks in Massachusetts to states with more lax rules like Indiana.