Castle Bravo: The Hydrogen Bomb That Shook the Pacific

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“Our land is our sacred property. It is all we have. And now it is destroyed. We can no longer use it because of contamination. We cannot go back and live in peace,” said the Mayor of Rongelap Atoll, almost 40 years after the Americans caused America’s worst radioactive disaster in history by testing the most powerful nuclear weapon yet. It was once one of the jewels in the beautiful necklace of the Marshall Islands, which stretch for around half a million kilometres in the Pacific. Today, it is uninhabitable. After the Americans detonated a hydrogen bomb not far away on 1 March 1954, its inhabitants had to be evicted. The effects of the radioactive radiation were felt by the inhabitants of the other Marshall Islands, and the American nuclear legacy will be irreversibly etched in the soil, vegetation and aquatic life for at least another half a million years. 

But once upon a time, the Marshall Islands were truly paradise. Their inhabitants had a reputation as some of the best fishermen and navigators in the Pacific, and their lifestyle was one of harmony. Food was abundant: it came from the sea and was harvested on the land. 

Then World War II cut sharply into their paradise. The Japanese chose the Marshall Islands as a strategic military outpost, and the Americans couldn’t help but come to liberate them in February 1944. But, as is so often the case with them, they did not want to leave after that. They had already defeated the Japanese in September 1944, but after the end of the war, they signed an agreement with the natives whereby they took control of their territory and turned it into a kind of annexed territory rather than return home. 

The sea homes of the locals have become a valuable American military outpost. The savages, as the natives were called, were of no interest to them, but the remoteness of the islands – ideal for testing nuclear weapons – was what attracted them most. 

Bravo project

The Americans have had experience of such experiments before, but only in the desert. Now they have started planning the Castle Bravo project to test the effects of the world’s most powerful hydrogen bomb yet. The Cold War was intensifying and the Soviets had a six-month head start. That’s when they blew up their own hydrogen bomb plane to study its effects. 

The Americans had to capture them. Ethical considerations were not an option, but on 1 March 1954 at 6.45 a.m. they dropped a hydrogen bomb at Bikini Atoll, presumably convinced that its effect would not reach the inhabited territories. 

The bomb had a yield of 15 million tonnes of TNT and was 1 000 times more powerful than the nuclear bomb dropped on Hiroshima nine years earlier. The fusion reaction was triggered by plutonium, whose radioactivity will continue to be present in the environment for at least half a million years, half of which is dangerous to humans. 

But they weren’t interested. The islanders of Bikini and Enewatak atolls had been evicted before, and the coral reefs had no value to them. The bomb, which exploded in the shallows when it touched the ground, making its impact even more powerful, instantly turned 23 small atolls into nothing. The crater created by the explosion was 75 metres deep and 2000 metres across. It is so large that it can even be seen from space.

The explosion created a fireball about 7000 metres in size. It was almost as hot as the centre of the sun. It sucked in water, mud and a million tonnes of coral. They immediately turned to dust, which coalesced into tonnes of radioactive uranium particles. These later fell back to earth. 

As the fireball reached its peak, it created a mushroom-shaped white cloud. Within a minute it was 1.4 kilometres high in the sky and 1.1 kilometres across; ten minutes later it was 4 kilometres high and 10 kilometres across. It was also seen from Kwajalein Atoll, 450 kilometres away. 

The previously inhabited atolls of Bikini and Enewatak were evacuated by the Americans in time, but the other atolls were not. They supposedly did not know that as much as 11 000 square kilometres of land would be contaminated, but radioactive particles, like snowflakes, began to fall on the ground, in the lagoons and on the inhabitants of the islands, which were also 450 kilometres away from the explosion.

It all went wrong or it all went as planned, depending on the interpretation. To this day, proponents of the first version, especially the US authorities, claim that their scientists had an unexpected accident. That they completely miscalculated the bomb’s power and it exploded with two and a half times more power than they had predicted. They assumed that the lithium-7 isotope would not react in the explosion, but it did. Since the bomb was made of 60% of this isotope, its yield was that much higher. 

It is also believed to have been stolen by the wind. It reportedly changed direction just before now and started blowing east instead of north. He reportedly changed his mind so quickly that Dr. Alvin C. Graves could no longer call off the bombing. Well, he could have, but that would have thrown the long preparations into disarray, and the Soviets would have had an even greater advantage over the Americans than they had had before. Calling off the launch was out of the question. 

But many people don’t believe that the experiment went a little wrong, especially not the people of the Marshall Islands. The documentation for Project 4.1 is a wake-up call.

Guinea pigs?

The Bravo H-bomb testing was exploratory, so they wanted to do a range of other research within it. Thus, Project 4 aimed to study the effects of the weapon, and within this, Project 4.1, with the working title: Investigating the response of human beings to large-scale beta and gamma radiation from radioactive dust in the event of a high–yield nuclear weapon explosion, was to be the focus of Project 4.1. 

The project was strictly confidential. The US authorities had already kept the Bravo project under wraps, but told no one about the 4.1 project. No one involved in it was allowed to talk about it, and everyone involved, as in war, was only allowed to know what they absolutely had to know. 

The project wanted to assess how badly people are injured when exposed to radioactive radiation and how they could best be treated. At the same time, they wanted to carry out a scientific study on radiation injuries in humans. 

The project was launched almost at the same time as the Bravo project. So were the inhabitants of the Marshall Islands deliberately exposed to radiation and turned into guinea pigs to see what would happen if there was a third world war? The affected islanders believe it, and many others do too. 

It was a truly unique opportunity. During war, injuries are not only caused by radiation and people’s health is also affected by their mental state, but now they could see the consequences of radioactive radiation in a completely clean and unspoilt way.

They were looked at closely. The islanders were observed in a military hospital, but 75 days after the explosion, the project was cancelled. In July 1954, it was decided to monitor the unwanted patients regularly: once every six months to start with, and then every twelve months thereafter, to keep up to date with the long-term effects of radiation exposure.  

It was many years later that the islanders learnt a small piece of the truth. In 1972, Ataji Balos, a representative of the Marshall Islanders, accused the US government of deliberately exposing them to radiation before the Micronesian Congress, and of choosing them as guinea pigs because their islets were remote and because “they are not white, but some brown natives on some remote islands in the Pacific”. He also accused them of having at least questionable, if not poor, health care.  

At the time, all documents related to Castle Bravo were still strictly confidential, but in 1994 the US authorities had to make them public. They showed that the 4.1 plan had been written before the Bravo project got under way. It is dated 10 November 1953 and the H-bomb exploded on 1 March 1954.  

The US government’s propaganda machine was immediately set in motion. Those in charge claimed that the dossier had been inserted after the fact and that the project was therefore not planned. Indeed, all other official documentation shows that Project 4.1 was decided on after the explosion and, according to official sources, was put into operation on 7 March 1954. The final report of Project 4.1 also ensures that the Bravo project did not include a biomedical programme.

Thus, US officials insist to this day that the exposure of innocent people to strong radioactive radiation was the result of miscalculations, not premeditation, and that the project was decided on the spur of the moment. When they saw the consequences of the explosion, they thought it would be a real shame to miss a once-in-a-lifetime opportunity for research, so they took it. 

Even if this were true, their actions were still controversial. The Marshall Islanders were never informed that they were the subject of the research, let alone asked for their consent to take part in it. 

Women without children, children with cancer

The final report of Project 4.1 shows that the Americans exposed 239 inhabitants of Utirik, Rongelap and Ailinginae atolls to radioactive dust. In addition, 28 Americans staying at Rongerik Atoll were injured. 

The people of Rongelap Atoll were the worst affected. The radioactive dust irradiated them with an absorbed dose of 1.75 gray, or 175 rads, the old unit of measurement. The inhabitants of Ailinginae Atoll received 0.69 gray, or 69 rads, the natives of Utirik received 0.14 gray, or 14 rads, and the Americans on Rongerik received an average of 0.78 gray, or 78 rads. The average person is not exposed to even 0.2 graye or 20 rads of radiation in a lifetime. 

The main problem was that the inhabitants of the islands had no idea what was falling from the sky. The radioactive dust was like snowflakes that magically covered them, but the children enjoyed playing with it. They and their parents unsuspectingly drank the water in which they fell, and for the first few days they really did not notice any problems. 

Then they suddenly became sick. They got diarrhoea, their hair started to fall out and their skin looked burnt. Rough sores appeared on their skin, oozing fluid. The people of Rongelap and Ailinginae were the worst affected, so American help came in the nick of time. 

When the Americans saw the consequences of radioactive dust blown in the wrong (or perhaps the right) direction by the wind, they evacuated the inhabitants of the islands at risk. Two hundred and thirty-six were transported to a naval hospital on Kwajalein Atoll and treated. The official report said that the wounds healed quickly, depending on how much radiation someone had been exposed to. 

Nobody knew anything about it at the time, and the evacuation of the islands was to remain secret, but Corporal Don Whitaker didn’t exactly agree with his superiors. In a letter to a local newspaper in Cincinnati, he described the poor condition in which the locals had arrived at the hospital. The authorities immediately informed the public that the patients were “well”. 

They were set up by photographs of a 7-year-old girl taken at the time and published a short time later. The girl was without hair. A close-up of the 13-year-old’s head and nape showed that his hair had also fallen out, except that his skin was peeling and he had a painful wound on his left ear. Blood tests on other islanders showed changes typical of radioactive irradiation.  

Lijon Eknilang celebrated her 8th birthday on the day of the explosion.  She subsequently had seven miscarriages as a result of the radiation. She remained sterile. She has never forgiven the Americans for having fooled her, because at that time neither she nor her parents knew anything about the dangers of the H-bomb. 

The Marshall Islanders are still feeling its effects today. “Since the bomb fell, the children have not been the same. My thyroid gland was removed. My son died of leukaemia. He was one year old when the bomb exploded,” recalled one local woman. No one told her anything, and neither did the other islanders. 

Her husband was mayor of Rongelap atoll at the time of the explosion, and was one of the few patients taken to America by the Americans to find out how much radiation they had been exposed to. The report called the group from the Marshall Islands ‘fishermen, savages by our standards’, and the mayor of Rongelap Atoll was said to be ‘what we called a savage, but a happy and useful savage’.

For the Mayor, the memories of those days are humiliating and, above all, bitter. “After the bomb, there were many other problems. Women were giving birth to children who were not like human beings. Those who managed to survive had problems with growth and also mental retardation.”

In the final report, the Americans officially assessed that burns do not pose a long-term risk, and that they could not find a pattern of other diseases that was irrefutably linked to radiation. However, they also noted that in the first five years after the accident, women at Rongelap gave birth to more stillborn babies and had more miscarriages than other women around the world, and they detected more developmental and growth problems in the children. Nevertheless, the effects of the radioactive radiation were considered to be mild.  

The true picture only emerged in later decades. Children began to develop thyroid cancer at a higher-than-average rate, and all those who were irradiated had thyroid problems at a higher-than-average rate. By 1974, as many as one third of the population of Rongelap Atoll had thyroid problems, and since the thyroid gland controls physical and mental development, mental disorders, lack of vital energy and developmental problems also emerged. 

In 1986, a study was published showing that 91% of islanders had a blood count characteristic of radiation, and that the Marshall Islands had more miscarriages and stillbirths than anywhere else. 

Glen Alkyl was a member of the Peace Corps at the time of the explosion. Looking at the locals, he could easily imagine what people would look like if World War III broke out. 

Radioactive dust over Japanese fishermen

But it wasn’t just Marshall Islanders who were affected. A few days after an article about them was published in a Cincinnati newspaper, news came out that shocked not only the American public but also the US government – the Japanese were also victims. 

Twenty-three crew members of the fishing boat Fukuryu Maru, or Lucky Dragon, were fishing for tuna in the Pacific Ocean at the time of the explosion. After the accident, the “dust of death”, as the radioactive dust is known in Japan, engulfed them too. 

The fishermen did not return to their home port near Tokyo until two weeks later. They showed every sign of exposure to radioactive radiation and their catch was contaminated. Panic reigned in Japanese fish markets. Although it was not officially reported, around a thousand more Japanese fishing boats are expected to suffer a similar fate. All of them were bringing home dangerous cargo.  

The Americans sent a doctor to Japan. He estimated that the fishermen would recover in less than a month, but six months after the accident, the 40-year-old Fukurya Maru fishing boat signalman died. That was when the Japanese government reacted. It accused the Americans of staging another Hiroshima, and the Americans replied that radioactive radiation does not increase with the power of the atomic bomb, so it was not their responsibility. 

Japanese scientists collecting data from fishing vessel records disagreed, and Sir Joseph Rotblat in London also contributed to the strained relations. He demonstrated the three phases of the bomb and showed that the fission phase at the end of the explosion increases the amount of radioactivity by at least a thousand times. 

But official Japan and America quickly reconciled: the Americans paid two million US dollars in compensation for Japan’s loss of fishing, and all surviving Japanese fishermen got two million yen each. 

Those who took part in the experiment could not escape the unexpected radioactive dust and radiation. One prominent scientist was on board a ship 48 kilometres from the blast. He and his crew members received real X-ray radiation. Sixteen crew members of the aircraft carrier USS Bairoko were exposed to so-called beta rays and started to get cancer. 

In 1980, the Bravo Project was named the worst radioactive dust accident of all US atmospheric experiments by the US non-governmental agency Bravo. 

Greenpeace, help!

Seven weeks after the explosion, or on 21 April 1954, experts told military officers that the inhabitants of the Marshall Islands should not receive even medical radiation, let alone anything more powerful, for at least the next 12 years, and very probably should not be exposed to radiation for the rest of their natural lives. 

However, the residents of Utrik atoll were returned home not long after they stopped receiving treatment on Kwajelein, and the locals returned to their radioactive homes in Rongelap only three months after the evacuation. There, they watched their health deteriorate for the next 28 years, but never got an answer as to why. No one would tell them what the radioactivity levels were on their island, or whether it was even safe to live there. 

They have been demanding ever louder that the Americans relocate them at their own expense, but nothing has been achieved. In mid-1985, the three hundred islanders had no choice but to call in the environmental organisation Greenpeace and persuade its members to transport them and 100 tonnes of their building materials at their own expense to the island of Majetto, some 180 kilometres away. Many stayed behind. They did not dare to return home, even though the Americans had built them new, supposedly safer housing. 

They no longer trusted them. The memory of a time when they felt like guinea pigs in an American laboratory experiment, rather than patients deserving of treatment, was still all too vivid. That their medical care was truly abysmal was confirmed 38 years later by the doctor who examined them every year. 

In one of his writings, he regretted that the Nuclear Energy Commission was research-oriented and therefore did not include basic health care for the population in its aid programme, but only paid for monitoring of what it was interested in researching. In effect, the islanders were not treated at all. 

The spread and deposition of radioactive material has also been detected in Australia, India, Japan, the United States and parts of Europe. The Bravo project has sparked international protests and calls for a ban on thermonuclear testing. 

It introduced Americans to a new phrase, radioactive dust, but it also told them that you cannot smell, see, feel or taste this invisible danger. 

Later, it was also learned that milk contaminated with a radioactive isotope of the so-called strontium-90 was in circulation, and that radioactive caesium-137 was detected in coconut milk from affected atolls. This has contaminated the earth’s surface and water, but also plants and trees, because they absorb it easily. For example, abnormally high concentrations of caesium were found in the bodies of islanders who had consumed contaminated coconut milk, so much so that they had to be evacuated.

In September 2012, the Special Rapporteur of the United Nations Human Rights Council wrote in his report that the effects of radiation range from almost irreversible environmental contamination, resulting in the loss of habitat and land, to the irreversible displacement of many people. And all this so that the Americans can become a military nuclear superpower once the tests have been completed.  

Data released in 2013 showed that between 1946 and 1958, the Americans conducted 67 atomic and hydrogen experiments on the Marshall Islands, with a total yield of 108 million tonnes. This is equivalent to 7200 bombs dropped on Hiroshima and 98 times the yield observed when nuclear weapons were tested in Nevada. 

“I don’t like the Americans and the American authorities. They have destroyed our culture,” says one local woman, rightly angry. But during the Cold War, no one said anything to anyone, let alone asked anyone anything. The US authorities only put their energy into launching the biggest publicity campaign ever. It was used to convince the people of Bikini that they were trying to turn something that was destructive into something that would be good for humanity and good for them. 

Some locals were indeed persuaded by the soldiers to move out of their homes voluntarily, others went because they didn’t even know they were moving permanently. The translators translated the American words so vaguely that they thought they would be back again soon. They took with them only the basic necessities, just like the inhabitants of the islands who were evacuated later. 

But then the Americans were their masters. They ruled the islands for more than four decades. The legacy of their rule abroad is similar to elsewhere: 43 000 islanders who are completely lost. 

But many Americans, especially soldiers, are proud of their actions. They could have turned around and left the islanders to their own fate, they say, but they stayed and helped. The American courts, too, have all in turn rejected complaints about compensation for the damage caused. 

When the Marshall Islands negotiated independence with the Americans in 1986, they agreed to pay the Americans $150 million to compensate them for the damage caused by years of nuclear testing, but agreed not to ask for anything more later. 

Why did they land? Because they had no chance against the superpower. They accepted the offer as the price of freedom, but the money soon ran out. More than 700 people exposed to radioactive dust or radiation died without being paid in full. 

Displaced and lost

But this is not the bitterest legacy of American rule in the Marshall Islands. Far worse is the the theft of the soul and self-sufficiency of its inhabitants. Once they lived off the sea and what the land gave them, now 90% of the education, health and transport systems are based on American donations. 

Kwajalein Atoll had to be handed over to the Americans. The locals had to move away to allow the Americans to set up a military base there. The islanders fished in the bay, while the Americans intercepted test missiles from California, 6 800 kilometres away. 

Where locals once lived, some 3 000 Americans have taken up residence in luxurious new buildings. Islanders were allowed to work for them, but also to live among them. They were allowed to move to the other side of the lagoon, to Ebay, where the Americans had made a settlement for so-called radioactive refugees on a good square kilometre of land. As many as 10 000 people are crammed in there, which is why the settlement has taken on the name of the Pacific Slum.

It is one of the largest in the world, and living conditions there are extremely poor. There are no trees, so there is no natural shade. Three families are crammed into one large room. There are many children, but they do not have a single playground. They play on a rubbish dump. 

Children and adults suffer from diseases common to both the developed and underdeveloped world. Many children suffer from malnutrition, and adults suffer from cardiovascular disease, diabetes, high heart pressure and stroke at a much younger age than in the rest of the world.

Since they were evicted from their homes, they can no longer survive on their own. Tuna used to be caught in the sea, but now they buy it canned. They watch American TV programmes and dream the American dream, but most of them are unemployed. 

The education system is poor and jobs are almost non-existent. The suicide rate among teenagers in the Marshall Islands is 100 times higher than in the US, even though 50 years ago their society did not even know the word suicide, let alone what it was. 

First the Americans destroyed their islands, then they turned them into their own garbage dump, where they dump their garbage from the West Coast of the USA. The rubbish includes toxic residues. In theory, they should be safely stowed away, but no one can guarantee that this is the case. In exchange for them, they get money, about USD 20 million a year. 

It also accepted US nuclear waste. Their logic was simple: some islands are already so contaminated that a few more nuclear waste really cannot harm them. But rising sea levels are already threatening their nuclear repositories. 

Their fish and other marine animals are still radioactive. The radioactivity has left the islands virtually devoid of visitors, which is bad for tourism and good for corals. They have partially recovered, but the detonation and subsequent exposure to radioactivity have caused the disappearance of 42 species of coral. 

To this day, it is still unknown how many casualties were actually caused by the US nuclear tests in the Marshall Islands. Bodies are still being recovered and tested, but researchers say with certainty that thousands of people were trapped in the cloud of radioactive dust.

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