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

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.

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.

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

On Nov. 26, 1941, Secretary of State Cordell Hull issued a note calling on Japan to withdraw from China and Indochina—terms Tokyo saw as impossible. The note confirmed to Japanese leaders that diplomacy had collapsed, accelerating plans for the Pearl Harbor strike (which had been formally approved Nov. 5).

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.

Japan's attack on Pearl Harbor caused heavy losses but failed to cripple the US navy

Japan’s air assault sank or damaged 18 warships (including eight battleships) and destroyed 188 aircraft, killing 2,403 Americans, yet all three Pacific Fleet aircraft carriers were absent and survived, and vital infrastructure like oil depots and repair yards remained intact—preserving core US naval power and enabling a rapid recovery. Watch original reporting here.

Should the US have entered into World War I?

America entered World War I in 1917, but had remained neutral until that point. President Woodrow Wilson addressed Congress, further underlining the USA's neutrality. Eleven weeks later, he asked for a declaration of war. With attacks by German saboteurs on an American munitions depot, it seemed he had no choice. But did he? This article asks what might have happened if the US stayed out of WWI.

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.

FDR stayed composed as he absorbed the news of Pearl Harbor

This video reconstructs Roosevelt’s steady, methodical response on Dec. 7, 1941, from his first briefing to drafting his speech to Congress. It demonstrates how FDR maintained composure and moved rapidly to prepare the nation for war.

How two US Presidents defined WWII and its aftermath

The National WWII Museum’s “To the Best of My Ability” podcast series delves into how Presidents Franklin D. Roosevelt and Harry S. Truman steered the US through World War Two.

2 months after Pearl Harbor, American libraries launched a drive to collect 10 million books for soldiers

The 1942 Victory Book Campaign—sponsored by the American Library Association, the Red Cross, and the USO—asked the public to donate books to both train and entertain troops. The national campaign exceeded its goal, collecting more than 10.2 million books.

FDR's Good Neighbor policy reversed the interventionism that had grown from the Monroe Doctrine

Franklin Roosevelt pledged in his 1933 inaugural address to be a "good neighbor" to Latin America and to oppose armed intervention by American forces. His administration withdrew troops from previous occupations and signed a multilateral agreement stating that no state has the right to interfere in another's affairs.

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 “Phoney War” was an eight‑month build-up to war

From September 1939 to May 1940, following their war declaration on Germany, Britain and France entered a phase of military inaction—even as civil defence measures, naval blockades, and rationing intensified at home. Skirmishes were limited, but the decisive fighting didn't begin until Germany invaded Norway and France in April–May 1940, abruptly ending the uneasy stalemate.

The perplexing Battle of Los Angeles in 1942 generated swaths of UFO conspiracies

On Feb. 24-25, 1942, weeks after the Pearl Harbor attack, a US military radar warned of enemy aircraft. A citywide blackout went into effect, powerful searchlights were lit up, and US forces fired artillery at what they believed to be the enemy. However, no confirmed enemy planes were ever identified. Eyewitnesses reported seeing large objects flying overhead, and much of the public speculated about UFOs and extraterrestrial attacks.

The British Royal Navy—not the US military—enforced the Monroe Doctrine for most of the 19th century

In the early to mid-1800s, the US lacked the ships and military power to prevent European nations from colonizing the Americas. Britain enforced this to protect its commercial interests by keeping rival European powers out of Latin America.

The USS Nevada was refloated within three months—and later fought at Normandy

Badly damaged at Pearl Harbor, the USS Nevada was raised by February 1942 after extensive salvage work. Repaired and modernized, it returned to action and bombarded German defenses during the D-Day landings.

US–Soviet hostility began long before the Cold War

US–Soviet tensions began decades before WWII. After the 1917 revolution, the US refused to recognize the Bolshevik regime and even sent troops to fight against it.

Why did the US make it illegal to sell sliced bread during WWII?

Pre-sliced bread has only been with us for almost 100 years, but during the course of World War II it was briefly banned to save on supplies like wax paper and stainless steel for the war effort. This Atlas Obscura article explores this amusing (though not at the time) bit of food during wartime history.

The 1941 Atlantic Charter was a World War II alliance and model for the UN

The Atlantic Charter was a pivotal 1941 agreement between Franklin D. Roosevelt and Winston Churchill, outlining shared goals for a post-World War II world rooted in freedom and self-determination. These ideals later inspired the founding principles of the United Nations.

Many years ago, the US dollar became the world's primary reserve currency

In 1944, 44 nations gathered in Bretton Woods, New Hampshire, to rebuild the global economy. The result? The US dollar became the world’s reserve currency, backed by gold.

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.

Key was initially opposed to the War of 1812

Like the majority of Americans, Francis Scott Key was opposed to the US declaring war on Great Britain, calling the move “abominable.” His feelings began to change after the British raided Washington, D.C. He joined the Georgetown Artillery shortly after.

Grace Hopper was inspired to join the armed forces after the attack on Pearl Harbor

Despite being too old to enlist and weighing below the required minimum to serve, Hopper was granted an exemption and assigned to work on the first electromechanical computer produced in the US. She and her team spent three months using the device to solve equations needed to design the implosion mechanism for the atomic bomb.

Roosevelt joined the NAACP and campaigned for anti-lynching laws—even receiving a $25K bounty from the KKK

Eleanor Roosevelt joined the NAACP board, lobbied for a federal anti-lynching law, and pushed to integrate the Army Nurse Corps—often going beyond the support her husband was willing to give to racial justice efforts. Her advocacy made her a target: The Ku Klux Klan placed a $25,000 bounty on her head.

In 2024, the US committed about $82.3B to foreign aid.

That year, 67.2% of foreign aid was for economic purposes, and the remaining 32.8% was for military purposes. Israel received more US foreign aid than any other country in 2024.

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.

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

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 idea for the Federal Reserve was conceived in secret in 1910—with bankers donning duck hunt gear for disguise while traveling to a remote country club on Georgia's Jekyll Island

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement

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 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.

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

In 2025, four executives from large tech companies were given positions in the US Army Reserves—including Palantir Chief Technology Officer Shyam Sankar, which reinforced Palantir's ties with the US military and its role as a leading defense partner.

See the most iconic photos from four decades of LIFE magazine

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

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

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

American dance legend Martha Graham, sometimes called 'the Picasso of dance,' refused to perform at the 1936 Olympics in Berlin and conceived the piece 'Chronicle' in response to the experience.

Watch a 1934 short film starring jazz legend Cab Calloway, a major figure in the Harlem Renaissance's music scene

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.

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

Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity, where it was purposefully grown in the English royal gardens at Kew, the Faculty of Medicine in Paris, and a few other locations.

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.