Einstein warned the president that splitting atoms could lead to powerful bombs

Manhattan Project explained

Driven by fears of a Nazi nuclear bomb, the Manhattan Project united leading scientists to build the first atomic weapons. Its success ended World War II, caused catastrophic human loss, and launched the nuclear age that reshaped global politics and science.

Building the first atomic bomb required unprecedented coordination

Creating the first atomic bombs demanded breakthroughs in physics, engineering, and logistics—uniting elite scientists with tens of thousands of workers across the US. This in-depth history explains how the Manhattan Project overcame those challenges.

Meet the the scientists of the Manhattan Project

This resource profiles the scientists behind the Manhattan Project—from Nobel laureates like Fermi and Bethe to controversial figures like Teller and Fuchs—showing how their ideas, rivalries, and choices shaped the development of the atomic age.

J. Robert Oppenheimer’s grandson says his grandfather would back nuclear power

While the "father of the atomic bomb" referred to the bomb as "an evil thing," after the Manhattan Project, he also described nuclear energy’s potential as an environmentally friendly solution to address the world's energy problem.

Oppenheimer reflected on the atomic bomb's legacy two decades later

In a 1965 CBS interview, J. Robert Oppenheimer discussed his role as Los Alamos director, expressing deeply mixed feelings about Hiroshima and Nagasaki and reflecting on how nuclear weapons had transformed the world since their first use.

The president has the sole authority to call for a nuclear strike

Under current US policy, the president alone can order the use of atomic weapons at any time without requiring prior approval from Congress—a power rooted in the president's role as commander in chief.

Spies working on the Manhattan Project propelled the Soviet bomb program

Soviet infiltration—most notably by Klaus Fuchs—smuggled detailed implosion-design and hydrogen‑bomb data from Los Alamos to Moscow, cutting the USSR’s development time by at least a year and enabling their first atomic test in August 1949.

The threat of nuclear annihilation reshaped global diplomacy

The first use of atomic weapons introduced the possibility of a war with no survivors. This article examines how nuclear fear shaped Cold War diplomacy and continues to influence international relations today.

Particle accelerators allow physicists to create controlled nuclear experiments

Before the 1930s, scientists relied on naturally radioactive substances to learn about atomic nuclei. The first atom was split in 1932 when John Cockcroft and Ernest Walton fired a beam of accelerated protons at a lithium atom, producing alpha radiation.

A primer on the president's nuclear football

During the Cold War, the United States and the USSR were forced to prepare for a nuclear strike at a moment's notice, leading to a new innovation: the so-called "football" (known as the chemodanchik in Russia), a bag containing nuclear strike plans, authentication codes, and likely a communication device, which attended the country's leader wherever they went. This easy-to-read piece breaks down the history and lore around the high-stakes quirk in nuclear governance.

Visualizing the chemistry of nuclear weapons

Nuclear weapons have devastating effects, but the science of how they work is atomically small. There are two main types of nuclear reaction: fission and fusion. The fission bomb produces immense energy by splitting an atom, the result of firing a...

The discovery of nuclear fission was facilitated by the discovery of the neutron

The discovery of the neutron provided scientists with a particle that could penetrate the nucleus and advance atomic physics. Otto Hahn was the sole Nobel recipient for the discovery of fission, despite collaborating with Lise Meitner and Fritz Strassmann.

One of Einstein's papers challenged quantum theory but helped confirm entanglement

In 1935, Einstein suggested that quantum mechanics was incomplete due to its strange implications about entangled particles. Their challenge led to decades of experiments that eventually proved distant particles could affect each other instantly.

The US once had a plan to nuke the moon

In the 1950s, the US considered detonating a hydrogen bomb on the moon as part of a Cold War show of force. Known as Project A119, the classified plan aimed to create a visible explosion from Earth to signal American dominance in the Space Race.

A US project proposed a 10-gigaton nuclear bomb capable of global devastation

Planned in the early 1950s by US scientists, Project Sundial aimed to create a 10-gigaton thermonuclear bomb—hundreds of times more powerful than any weapon ever built. Had it been tested, it was expected to cause global environmental catastrophe.

Experts argue that nuclear war is more likely than is commonly believed

The podcast highlights that many of the world's roughly 12,000 nuclear weapons—capable of triggering global collapse and nuclear winter—remain on high alert. Experts warn that this status, combined with limited public awareness, makes nuclear war disturbingly plausible.

Discovering how the dinosaurs went extinct may have helped avert nuclear war

This NPR Throughline episode explains how the 1980 discovery that an asteroid-driven dust cloud killed the dinosaurs inspired Cold War scientists’ fears of “nuclear winter”—a sunlight-blocking aftermath of nuclear war that may have discouraged leaders from launching one.

The story of the Manhattan Project's unused demon core

A 3-inch, 14-pound sphere of nuclear reactive plutonium-gallium was set to be delivered to the Pacific Theater in 1945 to become the third atomic bomb dropped over Japan. When Japan surrendered, it was returned to Los Alamos in New Mexico for experiment, where two scientists would die testing whether the core could reach criticality—where it would release intense energy—via the use of a dense reflector. Watch the story here.

A breakdown of nuclear fusion and what is impeding this near-limitless clean-energy resource

While today's nuclear reactors rely on fission, which releases energy by splitting heavy atoms, nuclear fusion releases energy by combining atoms together to form more massive ones. Fusion involves overcoming repulsive forces between the centers, or nuclei, of atoms, and, as of 2026, overcoming this repulsion takes more energy than is produced.

The origin of atmospheric science while testing nuclear weapons during the Cold War

The arms race between the US and the Soviet Union saw both countries stockpiling and detonating hundreds of bombs underground, underwater, and in the atmosphere. To better predict where nuclear fallout would travel after these tests, scientists developed models that would serve as a foundation for those used to explain atmospheric circulation.

The H-bomb is hundreds of times more powerful than the bomb dropped on Hiroshima

Unlike the atomic bombs dropped on Hiroshima, which relied on nuclear fission, the hydrogen bomb uses fusion to unleash vastly greater destructive power. Developed by both superpowers in the 1950s, it gave each the ability to destroy entire cities in seconds.

When Tesla died in 1943, the FBI seized his property for national security

Although Nikola Tesla had become increasingly eccentric in his later years, the US government wanted to ensure plans for a possible secret weapon didn’t fall into enemy hands during World War II.

A list of reasons against dropping the bomb on Japan

One of the perennial moral debates, the dropping of nuclear bombs on Japanese cities prompted strong, polarizing reactions at the time. This article breaks down one side of the argument: that the bomb was designed for defense, using it was illegal and racist, and that there were alternatives.

Wartime conferences exposed cracks in the US–Soviet alliance

At the Tehran, Yalta and Potsdam Conferences, Allied leaders coordinated WWII strategy—but deep disagreements over postwar Europe foreshadowed the Cold War. The USSR’s push for influence in Eastern Europe clashed with US and British calls for self-determination.

In the 1930s, Congress nearly passed a constitutional amendment requiring a national vote before declaring war

The Ludlow Amendment, proposed amid rising isolationism after World War I, would have required a national referendum before Congress could declare war, except in cases of direct attack. It was defeated 209 to 188 in 1938 after Roosevelt lobbied against it.

Albert Einstein's equations predicted black holes decades before their discovery

For nearly 50 years, scientists dismissed black holes as implausible oddities, despite solutions to the equations indicating their existence. But the 1970s discovery of intense X-rays from Cygnus X-1 and its massive hidden companion flipped the consensus.

'Men and nature must work hand in hand. The throwing out of balance of the resources of nature throws out of balance also the lives of men.'

- President Franklin D. Roosevelt (1882–1945)

Existentialism inspired Franklin Roosevelt and Martin Luther King Jr.

The Danish philosopher, sometimes called “the father of existentialism,” believed that individuals needed to resist the temptation of conformity and instead discover their authentic selves. His work became remarkably influential in the 20th century. In 1944, Roosevelt said that reading Kierkegaard made him understand how the Nazis could’ve enacted so much violence. In 1959, King wrote that existentialism was “especially meaningful for our time.”

Penicillin production was just behind the atom bomb in wartime priorities

By 1943, the US War Department made penicillin its second-highest priority—just after the Manhattan Project. Producing enough of the antibiotic for the D-Day invasion became a central mission of Allied science and industry.

View the evolution of atomic models, with four successively overturned between 1900 and 1926

Originally thought to be indivisible spheres unique to each element, the discovery of the electron by J.J. Thomson revealed them to be made of smaller particles. Ernest Rutherford's gold foil experiment uncovered the existence of nuclei, which Niels Bohr suggested were surrounded by electrons in fixed orbits. By applying quantum mechanics, Erwin Schrödinger replaced orbits with probability clouds.

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.

'Through this unique means, I convey to you and all mankind, America’s wish for peace on Earth and goodwill to men everywhere.'

- President Dwight Eisenhower (1890-1969) sending a message from space

Albert Einstein taught courses in Davos

This silent video from the 1920s shows footage of Einstein at Davos. The famous scientist spent time there, delivering public lectures on his theory of relativity as part of the town’s university courses.

Alfred Nobel invented dynamite and later used his fortune to fund peace prizes

Nobel stabilized dangerous nitroglycerin to create dynamite, revolutionizing construction and mining in the 19th century. Despite his success with explosives, he was deeply disturbed by their destructive potential and redirected his legacy toward rewarding human progress.

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

The Gasbuggy Project detonated a nuclear bomb to fracture underground rock formations

Part of Project Plowshare—a program aimed at finding peaceful uses for nuclear devices—the 1967 experiment sought to extract natural gas trapped within shale in underground New Mexico. Gas radioactivity was found to be excessively high for use without expensive processing, and the project was deemed an economic failure.

A Belgian Catholic priest was the first to come up with the idea for the Big Bang

In 1931, Georges Lemaître presented his radical idea that the universe came from a “primeval atom,” challenging the long-held belief that the universe had always existed. Einstein initially dismissed Lemaître’s work as having “abominable” physical insight, only to accept it later.

NUKEMAP lets you model the effects of a nuclear detonation anywhere on Earth

The tool was built by Alex Wellerstein, a historian of nuclear technology at the Stevens Institute of Technology in New Jersey. NUKEMAP uses declassified weapons data to calculate blast radius, thermal radiation, fallout patterns, and estimated casualties for any nuclear device dropped on any city. More than 50 million people have used it since its 2012 launch.

The US space program was built on former Nazi expertise through Operation Paperclip

After WWII, the US secretly recruited over 1,600 German scientists, including ex-Nazis like Wernher von Braun. They repurposed V‑2 rocket technology to create NASA’s core capabilities—pivotal in the Saturn V and Apollo missions.

For decades, the US has considered building a permanent nuclear waste repository

All nuclear waste would have been stored at Nevada's Yucca Mountain, but the Obama administration indefinitely stalled the project after intense community backlash. Spent fuel is now stored at more than 80 locations in 36 states, raising safety concerns.

Warren Buffett has worried that AI might end up being as consequential as the development of the nuclear bomb

Berkshire Hathaway chairman Warren Buffett is one of the many people who’ve come face-to-face with the downside effects of AI, and in particular, deepfakes. He was recently shown a deepfake of himself in a video, which caused him to worry about how bad actors will take advantage of the technology.

There is a secretive bomb-proof bunker located under the White House

Built in 1942 during World War II, the Presidential Emergency Operations Center lies beneath the East Wing. Designed to protect the president during air raids—and later nuclear threats—it remains a top-secret command site used during crises like 9/11.

Chernobyl pushed the world to create rapid-alert systems for nuclear accidents

In the aftermath of the disaster, nations adopted new agreements requiring immediate international notification of nuclear accidents. They coordinated emergency assistance—efforts led by the International Atomic Energy Agency to prevent future disasters from being concealed when radiation emergencies occur.

An NSA analyst helped avert nuclear war during the Cuban Missile Crisis

In October 1962, NSA cryptographer Juanita Moody headed analysis of U‑2 surveillance data and urgently produced intelligence on Soviet missile deployments in Cuba. Her reports drove high-level US decision-making, and were critical to avoiding nuclear war during the Cuban Missile Crisis.

Italian physicist Enrico Fermi (1901–1954) on the Standard Model

"If I could remember the name of all these particles, I'd be a botanist."

Kurt Vonnegut's 'Cat's Cradle' was inspired by the bombing of Hiroshima

The writer fought in World War II and witnessed the firebombing of Dresden, which he recounted in 1969's satirical "Slaughterhouse Five." Six years earlier, though, he wrote about the bombing of Hiroshima in "Cat's Cradle," channeling some of the horror he witnessed in Dresden to write about the dropping of the atomic bomb. (Some users may experience a paywall.)

Franklin D. Roosevelt's 1937 court-packing plan sought to expand the Supreme Court—and failed

Frustrated by Supreme Court rulings against the New Deal, Franklin D. Roosevelt proposed expanding the court in 1937. The failed plan triggered fierce backlash and is regarded as the last serious presidential attempt to alter the court's size for ideological ends.

The origin of the National Science Foundation and why World War II led to its founding

Before World War II, research institutions were funded by endowments or private companies whose priorities stifled the curiosity-driven science that fueled significant breakthroughs and innovation. The NSF was established in 1950 to promote independent scientific progress through basic research, which is focused on knowledge acquisition rather than commercial applications, conducted at national colleges and universities.

South Africa: the only nation to build nuclear weapons—and dismantle them by choice

During the 1980s, South Africa secretly built six uranium "gun‑type" nuclear bombs. In the 1990s, the government dismantled all its weapons and joined the NPT in 1991—the only country to fully reverse its nuclear program.

Engineers warned Challenger could fail, but were overruled

Engineer Bob Ebeling and four of his colleagues presented data to NASA officials and managers at NASA contractor Morton Thiokol the night before the launch about how cold temperatures could cause O-ring failure. Ebeling claims to have told his wife then that, "[Challenger is] going to blow up."