The mushroom cloud is not a unique signature of a nuclear bomb. A big explosion of any kind can create one, blowing a hole in the air and filling it with hot gases that rise rapidly, creating a powerful updraft of fire and smoke and vapor that vacuums in the storm of dust and debris caused by the blast and carries it all, elevator-like, straight up. A nuclear explosion, being so much bigger and hotter than any conventional explosion, creates a huge mushroom cloud that not only picks up a great volume of debris but also makes it radioactive. And because it can rise far above the altitude of the jet stream, the radioactive debris in the mushroom cloud from a nuclear bomb does not fall straight back to earth, but instead becomes entrained in upper-level wind currents, merging with the weather itself as it sweeps over oceans and continents, eventually raining back to earth where it will.
News of the hydrogen bomb test at Bikini atoll and the subsequent plight of the crew of the Lucky Dragon reached an American public largely unconcerned that what had happened on the other side of the world, in the middle of a vast ocean, was also happening here, over American farms and suburbs and cities. Between 1951 and 1955, the United States conducted forty-nine aboveground tests of nuclear devices at the Nevada Test Site, sixty-three miles north of Las Vegas. None involved hydrogen bombs, and some were small “safety” tests that produced little radiation and no fallout. In some tests the bombs were dropped from airplanes; in others they were exploded on towers.
The power of these devices varied considerably—from a small fraction of what was delivered when Little Boy went off 1,900 feet above Hiroshima, to some that were two or even three times as powerful as Little Boy. The resultant mushroom clouds carried hundreds of different fission products into the atmosphere, including at least twenty kinds of radionuclides—atoms with unstable nuclei that emit radiation—that were the most dangerous components of fallout. This continuing conveyance of radioactive debris into the atmosphere contributed to a perpetual global cloud of radioactive contamination also coming from nuclear testing by the Soviet Union and the United Kingdom. All of this debris sooner or later returned to earth.
People could experience “ambient” exposure to radioactive fallout simply by getting close to it or touching it on the ground. Or they could inhale or ingest it. One effective route of delivery turned out to be cows pastured on ground that received fallout. Cows that ate contaminated grass gave milk that contained concentrated radionuclides—milk that was, in turn, consumed by humans, mainly children.
Nuclear testing in Nevada was widely reported, of course, but the public paid little attention to fallout other than as a product of nuclear war, should one occur. Radioactive fallout had been discovered with the first atomic explosion—the test of the Trinity device. In his top-secret report on the test to President Truman, General Leslie Groves, who was the military head of the Manhattan Project, said that Trinity proved not only that the atomic bomb was powerful—it produced what were described as “tremendous blast effects”—but that it also sent skyward a lingering mushroom cloud that was more massive than anticipated and that rose to an altitude that surprised everyone.
The Manhattan Project scientists were convinced that a temperature boundary in the atmosphere at about seventeen thousand feet would be an impenetrable barrier to any cloud from the explosion that might reach that high. But the mushroom cloud from Trinity “surged and billowed upward with tremendous power” and in the space of five minutes had shot past seventeen thousand feet and reached an altitude of forty-one thousand feet. It was understood that the blast cloud would contain “huge concentrations of highly radioactive materials,” and Groves felt it necessary to explain how worrisome this new symbol of total warfare was:
The cloud traveled to a great height first in the form of a ball, then mushroomed, then changed into a long trailing chimney-shaped column and finally was sent in several directions by the variable winds at different elevations. It deposited its dust and radioactive materials over a wide area. It was followed and monitored by medical doctors and scientists to check its radioactive effects. While here and there the activity on the ground was fairly high, at no place did it reach a concentration which required evacuation of the population. Radioactive material in small quantities was located as much as 120 miles away. The measurements are being continued in order to have adequate data with which to protect the Government’s interests in case of future claims. For a few hours I was none too comfortable about the situation.
General Groves also informed the president that he had managed to keep local press coverage mostly confined to what the government’s official release said about the test, though some enterprising reporters had talked with a number of eyewitnesses who described the explosion. One of these, Groves said, was “a blind woman who saw the light.”
The extent of the fallout from Trinity had far more distant boundaries than General Groves realized. A few months after the Trinity test, the Eastman Kodak Company in Rochester, New York, started seeing blips and streaks on unexposed film it manufactured for industrial X-ray equipment. After some investigation, Kodak determined that the film was being contaminated by radiation emanating from the cardboard containers into which it was packaged. The cardboard had come from a couple of different suppliers in Iowa and Indiana—paper mills that drew their water from rivers flowing out of midwestern watersheds that were downwind of the Trinity test, albeit many hundreds of miles downwind.
The far-reaching effects of fallout were more dramatically observed in late January and early February 1951, following a series of Nevada nuclear tests that took place in the space of just over one week. The first bomb in the series, called “Ranger Able,” was a small one—less than one-half of one-tenth the size of Little Boy. But when it went off one thousand feet over the desert after being dropped from a plane it sent radioactive debris up in a mushroom cloud that reached seventeen thousand feet. Even though this was well beneath the jet stream, tracking planes followed the cloud all the way across the country. It arrived in New England after only two days. Along the way it became entangled with a storm, and radioactive snow fell on upstate New York. Ranger Able was followed one day later by “Ranger Baker,” a bomb sixteen times as powerful. This time the mushroom cloud rose to thirty-five thousand feet and again headed for the East Coast, where three days after the test radioactive snow fell in Central Park in New York City.
Subsequent tests in the Ranger series broke windows in Las Vegas and entertained people by lighting up the sky before dawn every couple of days. When “Baker Fox,” the final bomb in the series and a behemoth almost twice as big as Little Boy, was detonated on February 6, 1951, crowds of gawkers parked their cars in the early morning darkness along the highways outside the bombing range to watch the display. The blast again smashed windows many miles away, and the searing light from the explosion, first white then dark red, startled passengers on an airliner passing over Durango, Colorado, six hundred miles to the east. The mushroom cloud rose above forty thousand feet, caught the wind, and headed straight south over Las Vegas en route to Phoenix, Arizona; Brownsville, Texas; and on out over the Gulf of Mexico.
On went the tests, in Nevada and in the Pacific, always with the same fearful urgency that had become part of the national psyche in America and in the Soviet Union as the two countries built out arsenals capable of destroying the planet many times over. H. G. Wells had predicted as much, back in 1914 in a book titled The World Set Free, in which he imagined warfare in the 1950s involving “atomic bombs.” The arms race had, in fact, begun in 1939—the same year that Paul Müller discovered the lethal properties of DDT in his lab in Switzerland—when Albert Einstein sent a letter to President Roosevelt telling him about recent experiments in physics that might lead to a new kind of weapon unlike anything before.
Dr. Einstein explained that scientists in several countries—including Germany—were working on nuclear fission. If fission could be induced in a sufficiently large quantity of uranium, Einstein said, it might lead to a chain
reaction that would release “vast amounts of power and large quantities of new radium-like elements.” The likelihood of achieving this in the near future was all but certain. Fission, Einstein told the president, could be used for energy production or for building bombs. Einstein thought such bombs would be too big to be carried on airplanes, but one could perhaps be put on a boat and exploded near an enemy port, where it “might very well destroy the whole port together with some of the surrounding territory.”
An important consideration for America would be to secure a source of uranium, as there were poor stocks of the ore in the United States. Einstein pointed out that Czechoslovakia had good uranium mines, but that Germany had recently halted sales of the ore when it took control of Czechoslovakia. As this seemed to mean only one thing, Einstein urged that the United States—even though it was not yet at war with Germany—speed up its experimental work on nuclear fission at once.
After the war, the American fear of a competing nuclear state was transferred to a new enemy, the Soviet Union—whose 1949 test of an atomic bomb had been ahead of the timeline predicted by U.S. intelligence. It was followed by a hydrogen bomb in 1955. The Soviet program was believed to have been aided by an American husband-and-wife espionage team, Julius and Ethel Rosenberg, who supposedly handed over diagrams of atomic weapons and other documents that enabled Soviets to accelerate their development efforts.
It was actually unclear if the Rosenbergs gave up anything of real value to the Russians—or whether Ethel was even directly involved—but they were caught up in a new kind of public hysteria. The Rosenbergs were convicted of spying and were put to death in the electric chair at Sing Sing prison in 1953. Ethel’s execution was unusually brutal, as two applications of the current failed to kill her, and the third, which finally ended her life, set her on fire.
President Truman all but shut down America’s civil defense efforts at the close of World War II, but after the Soviet atomic test in 1949 and the outbreak of war in Korea a year later—seen by some as a distraction initiated as a prelude to a Soviet move in Europe—Truman launched a new agency called the Federal Civil Defense Administration in early 1951. Not surprisingly—given its ludicrous mission of protecting the United States in the event of nuclear war—the agency was widely distrusted, chronically underfunded, and in constant dispute with states and cities as to who was responsible for what.
The agency’s mission was to develop plans for the evacuation and sheltering of the entire U.S. population in the event of nuclear war. In practice, the agency mainly distributed pamphlets and short films—many aimed at schoolchildren—with advice on how best to survive a nuclear attack. It also plastered public buildings with the civil defense logo to indicate which ones were suitable as bomb shelters in the event of an air raid. But as the decade progressed, the concept of civil defense grew increasingly tenuous. Just one month after the Castle Bravo test at Bikini atoll, civil defense officials in New York said they had to completely rethink how best to respond to a nuclear attack in which a single hydrogen bomb could level the city. The only solution seemed to be a complete evacuation of eight million people—an improbable undertaking given the Air Force estimate that it could provide an advance warning of about one hour in the case of a Soviet attack with long-range bombers. A year later, citizens in Washington, D.C., were mortified to learn that Congress had allocated $115,000 for civil defense in the nation’s capital—compared with the $650,000 annual budget for the national zoo.
In the early 1950s, the civil defense advice dispensed to the public emphasized the likelihood that most people would survive a nuclear war. Anyone unfortunate enough to be close to ground zero of an atomic bomb explosion—from a weapon comparable to the bombs used against Japan or possibly a little larger—would, of course, be killed outright, as would many others within a radius of a couple of miles. But the effects of heat and blast and initial radiation that were the main threats diminished the farther away you were.
Civil defense officials also insisted that there was little to fear from the “radioactive clouds” sent high into the atmosphere in an atomic explosion, as the debris within them emitted much less radiation than was given off in the initial blast and would be “carried off harmlessly” and dispersed over a large area. This had been the case in bombings of Hiroshima and Nagasaki, where all of the radiation sickness had been attributable to exposure to “explosive radiation” and not to lingering radioactivity that precipitated out of the sky.
It was also assumed that atomic bombs would be routinely set to detonate high over their targets—which would maximize the blast effects and also reduce the volume of radioactive debris sent skyward. People were told that it would be safe to leave cover “after a few minutes” following an atomic attack in order to assist the injured and help fight fires that were likely to have started. The notion that an atomic detonation would render a large area uninhabitable for a long time was dismissed as a “myth.” The U.S. Department of Defense said that for fallout to become a significant danger over a longer period would require the simultaneous explosion of “thousands” of atomic bombs.
Of course, as Castle Bravo demonstrated, a single hydrogen bomb could easily be a thousand times as powerful as an atomic bomb, and as the U.S. and Soviet nuclear arsenals shifted to hydrogen weapons, everyone had to rethink the meaning and nature of nuclear warfare. An aerial burst of a hydrogen bomb could be expected—depending on the size of the weapon—to cause massive damage as much as twenty miles away from ground zero and would fill the sky with tons of deadly radioactive debris. By the end of the decade fallout was seen as the major threat in a nuclear exchange that would kill millions of people initially and pose a continuing danger to tens of millions in its aftermath. This meant that, in theory at least, everyone in the United States needed access to a fallout shelter with supplies of food, water, medicines, and other necessities that could last at least two weeks. In 1955, the Civil Defense Administration spent $8.3 million trying to develop “survival plans” for communities across the country—a grim undertaking that in the end seemed pointless.
The folly of civil defense planning grew in direct proportion to the increasing danger inherent in a nuclear exchange with the Soviet Union. In fall of 1957, the Russians launched Sputnik, the first manmade earth satellite—gaining a shocking advantage over the U.S. space program and signaling that the Soviet Union would soon be capable of attacking the United States with rockets armed with nuclear warheads. This would cut any advance warning of an attack from an hour or two to something like fifteen minutes—rendering meaningless the concept of mass evacuations from targeted areas.
The Americans and the Soviets had both been working on missile systems since World War II, and in the late 1950s and early ’60s, the nuclear arsenal was rapidly deployed among growing fleets of long-range, land-based rockets and missiles that could be launched from submarines anywhere in the world. Armageddon, which had been coming into view since Trinity, could now be envisioned as two great shadows rising from the earth simultaneously and passing each other in opposite directions above the atmosphere, curving toward the end of all things in a white-hot hell of thermonuclear doom.
It was understood, of course, that not every American city would be targeted. But the lesson from Castle Bravo and the tests that followed was that living through a nuclear attack was only the first step in surviving whatever would come after that, as radioactive fallout would prove similarly deadly over a much greater area. Nuclear warfare was a two-headed demon that killed whatever was close to the fire and poisoned everything else.
In 1958, a high-ranking civil defense official declared that the “saving grace” in a nuclear attack was that anyone who wasn’t vaporized in the initial blast would have some time to reach shelter before the fallout began to come down. But the original plan to build a nationwide system of fallout shelters never happened. Civil defense officials had imagined an elaborate complex of underground community shelters, protected areas in schools
and other public buildings, and subsidized private shelters for individual property owners. But the cost of such a system—estimated at a then unimaginable $300 billion—was prohibitive. In 1957, President Eisenhower rejected a more modest proposal for a $40 billion national shelter system, on the novel theory that total nuclear war was an unacceptable proposition. “You can’t have this kind of war,” Eisenhower said. “There just aren’t enough bulldozers to scrape the bodies off the streets.” By the 1960s, the question some civil defense planners had begun to ask was whether in the event of nuclear war “the survivors would envy the dead.”
Anxiety over the prospects of nuclear confrontation—mixed with a growing awareness of the mushroom clouds rising regularly over the American desert—were reflected in what became a science fiction subgenre unto itself, the “radioactive mutant” film. The prototype—a giant lizard called Godzilla—came from Japan in 1954 and gave rise to a string of B-movies produced in America, all formulated on the idea that exposure to radioactivity could change the nature and appearance of someone or something, and always for the worse. One favorite was a 1957 film called The Amazing Colossal Man, about an army officer injured in a nuclear test who suddenly grows to a height of sixty feet—a size at which insufficient blood supply to his brain sends him rampaging. Another was Them!, a surprisingly well cast and ingeniously written shocker that came out the same year as Godzilla. It was about an outbreak of radioactively enhanced killer ants that had morphed to the size of Studebakers and developed a paralyzing scream. These silly but nervous entertainments came after a more sober and cautionary issuance from Hollywood, the 1951 classic The Day the Earth Stood Still, in which an alien arrives on earth accompanied by a robot with immense powers. Their mission is to inform the planet’s inhabitants that if they continue the development of nuclear weapons an interplanetary police force would have no choice but to destroy the earth.
On a Farther Shore Page 25