It was noisy, busy, frightening, a world far removed from their isolated life up on a detached coral chain, far distant from a culture that had been based for hundreds of years on the stark simplicity of lagoon fishing. On Kwajalein, then as now a fully functioning American military base, all was stark, and little was simple. There was food and water in abundance. Too much abundance, many say today, since this was where the Bikinians began seriously and lethally to modify their diets, adding Spam, Coca-Cola, white sugar, and flour—and to change their working habits, to become what many regard them as today, participants in a handout culture. Few would dispute that from this moment on, the exiled Bikinians began to change, their native attitudes steadily eroded and diluted as the years away went on: Kwajalein is where the great alteration began to take hold.
Within months the U.S. government swiftly realized how unsuitable it was for the Bikinians, especially the growing number of newborn children, to be living in tents on a military airstrip. So in November 1948 they were moved for a third time, now to a tiny uninhabited speck in the southern Marshalls called Kili Island, a place that neither was an atoll nor had a lagoon. The island has no harbor, and during high seas a landing can be impossible. Airdrops from military cargo planes have to be arranged still, when sea conditions are too trying. A grass airstrip theoretically allows Air Marshall Islands access, but flights are few and very far between. Nonetheless, Kili is where the Bikinians, now transmuted from unwilling atomic exiles into perpetual atomic nomads, have been based ever since 1948. It now seems they may never go home.
If this proves to be so, it will be for many reasons—one being the obvious and long-lasting radiological contamination of their home in 1946, in the aftermath of the Crossroads Baker shot. But their exile is also a consequence of their atoll being massively polluted yet again, by the one most disastrous bomb for which Bikini has become most notorious, and which was exploded eight years later, on March 1, 1954: Castle Bravo.
By this time, the mid-1950s, there was no doubt that the Pacific was the place to test the truly big bombs of the future. On January 19, 1950, President Truman had made his decision. The superbomb, the thermonuclear fusion bomb, was to be made, and tried out—and it was to be employed as a bargaining chip with the Russians. The first prototype, George, had been tested in 1951; a bigger version in 1952. And now this one. The first potentially deliverable American thermonuclear weapon,7 a classic hydrogen bomb, it was code-named Castle Bravo. It remains by far the biggest nuclear weapon ever exploded by the United States, and its enormous and little-anticipated explosive impact resulted from two big mistakes, a combination of a major technical miscalculation and mulish stupidity.
History has left someone to blame for the error: a brilliant physicist with a curiously interesting stake in the nuclear world. He was named Alvin Cushman Graves, and a previous mistake with fissile material in 1946—a mistake not his own but one that killed the man who made it—very nearly killed him, too. That Graves survived the accident, and then recovered sufficiently to preside over the disastrous 1954 Castle Bravo test, was probably not entirely unconnected with his cavalier, cocksure attitude toward radiation risks from fallout. Such risks, he once famously declared, were “concocted in the minds of weak malingerers.”
The accident Graves survived was the second of the two lethal accidents that famously involved the Los Alamos lab’s notorious Demon Core. Graves was the man standing just behind Louis Slotin when the pair of three-inch hemispheres of nickel-beryllium-plated plutonium briefly touched each other and a sudden surge of blue light and viciously dangerous radiation flooded the room. Graves was partly shielded by Slotin’s body, but he nevertheless received a sufficiently scalding bath of gamma rays, X-rays, and neutrons to kill him. Few of his doctors thought he would live. He was in the hospital for weeks, briefly lost all his hair, and developed serious neurological and vision problems. But to the amazement of all, he then slowly and steadily got better, ultimately recovering almost totally. Physically at least, there was little scarring, except one small spot of baldness, which he liked to display.
Infamously disdainful of the supposed dangers of atomic fallout, the nuclear accident survivor Alvin Graves ordered the fateful firing of the Castle Bravo thermonuclear weapon, the biggest of all American nuclear tests. National Nuclear Security Administration.
He eventually became well enough to be appointed—though at this remove, and considering what then happened, it is surely right to wonder at the wisdom of his appointment—scientific director of the Castle series of thermonuclear bomb tests. He swiftly became the most enthusiastic advocate of these new weapons—not least because he was well aware that the Soviet Union’s nuclear program was catching up fast.8 Once he arrived at the Enewetak headquarters of what were now called the Pacific Proving Grounds, he made one thing abundantly clear to his staff: since he had survived the very worst that the atom could throw at him, he would stop at nothing to detonate the Bikini-based fusion device that was now in his care.
The bomb designated for the Castle Bravo detonation was an innocent-looking steel cylinder fifteen feet long, four feet in diameter. It looked rather like a large propane tank. It had been designed at Los Alamos, where, to suggest its innocence of purpose, it had been given the code-name the Shrimp. It had been shipped in great secrecy—lights off at night, aircraft and destroyers keeping pace with the cargo ship—to Enewetak in February, and was taken by barge to Bikini, with tarpaulin wraps to prevent the unauthorized curious glimpsing its size and shape. There it was suspended from the ceiling of a large shed, called the shot cab, that had been erected on an artificial island built on a reef off Nam Island, at the very northern tip of the atoll. A causeway connected the shot cab with dry land; the wires that would lead to the electronic firing bunker snaked across the sandbanks and coral reefs and past the Bikinians’ now long-abandoned houses, to the tiny sliver of Enyu Island, twenty miles away.
At the end of February, all staff members were evacuated from Bikini and all ships were removed from the lagoon. Only the firing crew, nine men buried beneath concrete a dozen feet belowground, stayed behind.
Before the firing button was pressed, there were two serious uncertainties. The first was just how big this bomb would be. The Ivy Mike explosion of sixteen months before had been a thumping ten megatons, spectacular and memorable—and when that bomb blew up, it did so exactly as powerfully as the physicists had predicted. But Castle Bravo was using a solid rather than a liquid source of hydrogen—the hydrogen that would be compressed with such force and heat as to make it undergo fusion, and release the massive amount of energy that would cause the explosion. The solid compound in the new bomb was lithium deuteride, an amalgam of lithium and isotopic hydrogen. And no one knew exactly how much hydrogen it would release, or how big the detonation would be.
The testers would soon find out. And because of the other uncertainty—over the weather and, more specifically, the direction of the winds on detonation day—a great many others would find out as well.
For several days before the test date, the winds had been blowing in what was considered an acceptable direction: toward the west, where they would carry any radioactive fallout over an empty expanse of sea. The United States had declared a 57,000-square-mile “danger area” in an official Notice to Mariners, suggesting that craft keep away if possible, but without stating why. Had matters stayed as they were, the detonation would have caused little obvious harm.
However, on the night before the planned blast, February 28, the wind began to veer toward the east, away from this designated danger zone. Matters then got worse. As the sun inched up on the morning of the shot, meteorologists started reporting that at upper altitudes a powerful gale was now blowing directly from Bikini and toward the other populated atolls of the Marshalls, most notably in the direction of Rongelap,