End Times

The Morning We Learned How to Destroy the World

Seventy-four years after the end of World War II, we’re still living with the existential risk of nuclear holocaust — and it all began on a patch of desert called the Trinity Site

Credit: Historical / Contributor/Getty Images

Asteroids, supervolcanoes, nuclear war, climate change, engineered viruses, artificial intelligence, and even aliens — the end may be closer than you think. For the next two weeks, OneZero will be featuring essays drawn from editor Bryan Walsh’s forthcoming book End Times: A Brief Guide to the End of the World, which hits shelves on August 27 and is available for pre-order now, as well as pieces by other experts in the burgeoning field of existential risk. But we’re not helpless. It’s up to us to postpone the apocalypse.

TThe chief asset of a missile range is its emptiness. At maximum size — its dimensions shrink and grow like a shadow depending on what its owners the U.S. Army is testing on a given day — the White Sands Missile Range in central New Mexico covers about as much land as the state of Connecticut. Nearly all of it is vacant, devoid of buildings or roads or even the few animals that live in the flat, dry scrub the Spanish called the Jornada del Muerto, the Journey of Death. It’s a name that seems almost too perfect, like that of the Sierra Oscura, the Dark Mountain, which loomed to the east as I drove up on an April morning to Stallion Gate, the northern entrance to the missile range and the one closest to Trinity Site.

It was to see Trinity that I had come to New Mexico and the White Sands Missile Range. We think of Hiroshima as the dawn of nuclear weapons, but it was here at Trinity Site that the very first nuclear bomb was detonated, the work of more than 100,000 people — from ditch diggers to dozens of past and future Nobel Prize-winning scientists — employed by the U.S. government’s Manhattan Project. Hiroshima, Nagasaki, the Cuban Missile Crisis, the North Korean standoff, and whatever might come next — it can all be traced back to what happened here in New Mexico on July 16, 1945 at 5:30 a.m., when a successful atomic test resulted in an explosion more destructive than anything humans had caused before.

Trinity, however, inaugurated more than just the nuclear age. It ushered us into the era of man-made existential risk, an era that we live in still. Before Trinity, the world could end, and nearly did, as mass extinction events repeatedly erased most of life on Earth. But the cause each time was natural: supervolcanic eruptions, a collision with an asteroid, sudden and drastic climate change. After Trinity, though, human beings could be the authors of our own annihilation. All the existential risks that would follow — anthropogenic climate change, biotechnology, artificial intelligence — flow from what happened at Trinity, a hinge point in human history. So you can bet I wanted to see the place where it all began.

Robert Oppenheimer told a Senate panel that “before we made our first test of the atomic bomb, we were sure on theoretical grounds that we would not set the atmosphere on fire.”

The conditions the night before the test on July 16 were atrocious — heavy rain and lightning, which is not ideal when there are miles of electrical cable snaking through the open desert and about 13 pounds of highly radioactive plutonium, wrapped in wires and screws and silver and gold and high explosives, all mounted on top of a hundred-foot steel tower. But there was no time to wait for better weather. Harry Truman — who had been president for barely three months and had only been told about the Manhattan Project when he assumed the office after Franklin Roosevelt’s death in April of 1945 — was due to meet the day after the test with Soviet premier Joseph Stalin. A successful test of the atomic bomb would be a powerful card for the new president to play as he charted the endgame of the war with his current ally and soon-to-be adversary. Trinity may have heralded a new era of man-made existential risk, but as ever it was immediate politics that drove the decisions on the ground, not any reckoning with truly long-term consequences. With one exception.

In 1942, the Hungarian American physicist Edward Teller ran some calculations and concluded that an atomic bomb might just possibly create enough heat to ignite the atmosphere and the oceans, causing a global inferno and the end of the world. When Robert Oppenheimer, the scientific leader of the Manhattan Project, told the physicist Arthur Compton about Teller’s figures, the older man reportedly responded in horror. “This would be the ultimate catastrophe!” Compton recalled in an interview after the war with the author Pearl Buck. “Better to accept the slavery of the Nazis than run a chance of drawing the final curtain on mankind!”

According to Buck, Compton told Oppenheimer that if additional calculations showed that the odds of igniting the atmosphere with a nuclear explosion were more than approximately three in one million, all work on the bomb should stop. About six months before the Trinity test, Teller and the Polish-American nuclear scientist Emil Konopinski produced a report on the subject, titled “LA-602: Ignition of the Atmosphere with Nuclear Bombs.” They concluded that it would be virtually impossible for even a much larger bomb than what would be tested at Trinity to create such a runaway fusion reaction and end the world.

“Virtually impossible” was good enough for wartime, so the work on the bomb continued. After the war, Oppenheimer told a Senate panel that “before we made our first test of the atomic bomb, we were sure on theoretical grounds that we would not set the atmosphere on fire.” At the time, though, not everyone may have been fully convinced. The night before the test, the Italian American physicist Enrico Fermi offered to take wagers on whether the bomb would indeed ignite the atmosphere — and if so, whether it would merely destroy New Mexico or the entire world.

Fermi was joking — mostly. But as Richard Rhodes writes in his magisterial history, The Making of the Atomic Bomb, “a new force was about to be loosed on the world; no one could be absolutely certain — Fermi’s point — of the outcome of its debut.”

The LA-602 report was a footnote in the history of the Manhattan Project, but it holds a special place in existential risk studies. It marked the first time humans had tried to figure out in advance whether their actions could bring about the end of the world. “It’s the first technical assessment of an anthropogenic existential risk, rather than a religious one, or one related to a natural hazard,” Jason Matheny, the former director of the government’s Intelligence Advanced Research Projects Activity (IARPA), told me. The debate over the existential dangers of biotechnology, the dueling visions about the threat from artificial intelligence, even this book — they can all be traced back to LA-602, a report that wasn’t even declassified until 1973.

As it turned out, the Trinity test demonstrated that for atomic weapons at least, it wasn’t what would happen if they went wrong that we should fear most. It’s what would happen when they went right.

WWith 20 minutes to go before ignition, Sam K. Allison of the University of Chicago began the world’s first countdown over a loudspeaker. As Allison reached the last few seconds, a local radio station began broadcasting on the same wavelength, overlaying Tchaikovsky’s “Nutcracker Suite” upon the falling numbers. Twenty miles away, observing the test site from Compania Hill, Edward Teller began making everyone nervous — or more nervous, at least — by offering to pass around suntan lotion he had brought. At 5:29:45 a.m., the Trinity bomb detonated.

Today, Trinity Site is fenced in from the desert. There is bright yellow grass, surrounded by the greener brush that extends out to the Sierra Oscura. Near the center of the site is the actual and first Ground Zero, the spot where on July 16, 1945, a hundred-foot steel tower stood, topped by what the Manhattan Project scientists called “the Gadget.” (The tower itself was called Zero; the ground at the foot of the tower was named Ground Zero, which is where the term originates.)

Ground Zero is memorialized with a stone obelisk mined from nearby volcanic rock — black and brown stone made by fire, to represent the ultimate fire. A plaque states the facts of what happened that day in the simplest terms: “Trinity Site — where the world’s first nuclear device was exploded on July 16, 1945.”

Beyond the obelisk, I could see black-and-white historical photos arranged against the fence. Between portraits of Manhattan Project scientists and images of the Gadget itself was a frame-by-frame series of the milliseconds after the Trinity bomb exploded.

At 0.006 seconds there is a bubble of perfect light, as if the dawn itself had blossomed suddenly out of the desert ground. The heat of the blast is thousands of times hotter than the surface of the sun, and the light in that single moment was a dozen times brighter. At 0.025 seconds, the bubble head keeps rising, while a fringe of fire spreads across the ground. It will carve a crater half a mile across, and suck up hundreds of tons of sand into the blast interior. Later the silica in the sand will adhere to radioactive particles and rain back to the surface as something wholly new: bright green trinitite, also known as Alamogordo glass. For decades after, tourists will collect shards of trinitite as souvenirs from the site, even though removing it is technically illegal.

At 0.053 seconds, that perfect bubble begins to lose its clarity, becoming diffuse and unfocused, as if overwhelmed by its own energy, while the inferno at the surface expands, gouging out the earth below. At this point, every living thing within a radius of a mile is dead, or will be soon. At 0.10 seconds, the blast looks like nothing less than a halo ringing the head of some Renaissance painting of Christ, as the exposure itself begins to degrade. The atomic heat has made the air glow luminous, as the force of the shock wave expands outward, shredding the matter in its path. Everything is ravaged, everything is burned.

At 15 seconds after detonation comes the familiar image of the mushroom cloud, what the art historian John O’Brian called the “logo of logos in the 20th century,” a symbol that would shadow humanity for decades to come. That mushroom cloud — like nothing seen on Earth before — is the result of the intense heat at the heart of the blast, causing the air to rise in a column, before it spreads out in a cap.

“A new thing had been born; a new control; a new understanding of man, which man had acquired over nature.”

Less than a minute after the explosion, Enrico Fermi stood up and released slips of paper into the air. He estimated from their deflection in the blast wave that the Trinity explosion had released the equivalent of 10,000 tons of TNT. Fermi was off, but his impromptu experiment proved far more accurate than the Manhattan Project’s conservative pretest estimates of between 500 to 7,000 tons of TNT. In the end, Trinity’s destructive power was close to 21,000 tons of TNT. Before the test, some of the senior Manhattan Project scientists organized a betting pool with a one-dollar entry fee, guessing the size of the explosion. Isidor Isaac Rabi, a physicist who’d come late to the test and took the last available bet in the pool, won with a guess of 18,000 tons.

Entire books can and have been filled with the testimonies of those who witnessed Trinity’s dawn. There is the scientific reaction and the military one, the religious and the poetic. But of all the words spent in witness I prefer those of Rabi, who had filled the tense night before the test playing poker:

“A new thing had been born; a new control; a new understanding of man, which man had acquired over nature. [. . .] Then, there was a chill, which was not the morning cold; it was a chill that came to one when one thought, as for instance when I thought of my wooden house in Cambridge, and my laboratory in New York, and of the millions of people living around there, and this power of nature which we had first understood it to be — well there it was.”

Three weeks after the test, the B-29 bomber Enola Gay took off from an air base on the Mariana Islands and flew toward Japan. A new atomic bomb was nestled in its bombing bay. At 8:15 a.m. local time on August 6, at 31,000 feet over the southwestern Japanese city of Hiroshima, the Enola Gay released its payload.

The bomb detonated 1,900 feet above the city of 255,000 people. Within a millisecond, the heat was so intense that as far away as 2.3 miles from Ground Zero, the temperature of a person’s skin could be raised to 120 degrees. Within minutes, nine out of 10 people within a half-mile radius of Ground Zero were dead, their bodies burned away to black char. The suffering of those who survived defies description, though it remains seared in the memories of victims like Setsuko Thurlow, who was a 13-year-old girl in Hiroshima the morning the bomb was dropped. What she witnessed was still vivid in her mind 72 years later, when she co-accepted the Nobel Peace Prize for the International Campaign to Abolish Nuclear Weapons (ICAN). “When I remember Hiroshima,” Thurlow told the audience in Oslo, Norway, “the first image that comes to mind is my four-year-old nephew, Eiji — his little body transformed into an unrecognizable melted chunk of flesh. He kept begging for water in a faint voice until death released him from agony.”

Some 70,000 people likely died as a result of the initial blast, heat, and radiation, and thousands more would die from injury and radiation-induced cancer in the months and years that followed. As high as the numbers were, though, it was not the death toll alone that set Hiroshima, and later Nagasaki, apart. America’s incendiary bombings of Tokyo with conventional weapons in 1945 had killed even more people, but that had required the work of 300 planes dropping 8,000 bombs over the course of two nights. Hiroshima had needed but one plane, and one bomb, a bomb of unimaginably concentrated destruction.

After the atomic bombings, it was said to Leo Szilard — a Hungarian-born physicist whose work had helped make Trinity possible and who had been one of the few voices urging that the atomic bomb not be dropped — that it was a tragedy for scientists that their discoveries were used for destruction. No, Szilard replied, it is not the tragedy of scientists. It is the tragedy of mankind.

Scientists move civilization forward through their pursuit of knowledge, but Trinity demonstrated that their pursuit can inadvertently create the conditions for our own doom. Existential threats can be brought into the world not by those who wish to end it, but by those who hope to better it. Intentions don’t matter for the fate of the world — results do. And today, 74 years after the end of World War II, we’re still living with the consequences of those results.

Update: This piece has been updated to clarify the mechanism of the Hiroshima bomb.

Journalist, author, dad. Former TIME magazine editor and foreign correspondent. Author of END TIMES, a book about existential risk and the end of the world.

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