The vessel called Daigo Fukuryu Maru, Japanese for “Lucky Dragon 5”, did not turn out to be particularly lucky. It was a Japanese deep sea fishing boat, designed to catch tuna, which was built in Wakayama. Under-powered and incapable of high speeds, it was frequently plagued with engine trouble.
On the voyage under discussion here, its fifth, the Lucky Dragon departed its home port of Yaizu, in the Shizuoka Prefecture, on January 22, 1954, with 23 crew members on board and the rather inexperienced 22-year-old Captain Hisakichi Tsutsui at the helm. The crew had set off to go fishing in the Midway Sea near Midway Atoll, but they lost many of their trawl nets to rough seas. Captain Tsutsui altered course southward, seeking easier fishing waters. Over the next five weeks or so, he kept pushing his boat further and further, sailing more than 3,700 kilometres out into the Pacific Ocean to a spot in the vicinity of the Marshall Islands archipelago. These islands are a sprawling chain of volcanic islands and coral atolls in the central Pacific Ocean, midway between Hawaii and the Philippines.
At 6:45 a.m. On the 1st of March, the 23 men aboard the Lucky Dragon had their nets deployed and were fishing for tuna. The sky was paling in the short pre-dawn tropical twilight and they were expecting the sun to rise anytime soon. Suddenly and astonishingly, it seemed that the sun did burst onto the horizon – but in the west, not the east!
In 1954, the Cold War between the two former allies who had defeated the Axis Powers was gaining intensity. The USA and USSR, respectively championing capitalism and communism, were engaged in an intense nuclear arms race that was entirely irrelevant to their claimed ideologies. The Americans, who had been the first to make a nuclear bomb (and had immolated two Japanese cities to prove it) had gone on to develop a newer kind of weapon, the thermonuclear “Hydrogen” bomb, whose destructive power was many times greater than the nuclear fission based “Atomic” bomb. This new weapon had an explosive power of 15 megatons, i.e. equivalent to 15 million tons of TNT, a thousand times greater than the bomb that had flattened Hiroshima (15 kilotons). It was this gigantic weapon the American Atomic Energy Commission (US-AEC) had detonated that morning on Bikini Atoll, a part of the Marshall Islands in the equatorial Pacific. The test, called Castle Bravo, was the first test of a hydrogen bomb.
In fact, Castle Bravo was much more powerful than American nuclear scientists had thought. They had expected a four- to six-megaton explosion, but its actual yield was three times greater. As a result, the effects were much more widespread than predicted. The bomb blew a gigantic crater into the Bikini Atoll, still clearly visible in satellite images. It also sprayed radioactive contamination across an enormous area of the Marshall Islands and the Pacific Ocean. The US-AEC had created an exclusion perimeter of 50 kilometres radius for U.S. Navy vessels, but the radioactive fallout was dangerously high as far out as 320 kilometres. Nor had the AEC warned vessels from other nations to stay out of the exclusion area.
The two Superpowers were immediately followed into the crazy nuclear labyrinth by Britain and France, later by China and Israel, and of course still later by India and Pakistan – but not by the only country that has suffered casualties to both nuclear and thermonuclear weapons
The men on the Lucky Dragon were catching tuna only 145 kilometres away and – further bad luck – were downwind from Bikini Atoll.
They saw an incredibly bright flash, brighter than a hundred suns and that seemed to actually brighten further, and then the western sky lit up as a colossal fireball, fully 7 kilometres in diameter, rose up from Bikini Atoll. The blast from the thermonuclear explosion reached them a few minutes later, rocking and nearly capsizing the Lucky Dragon.
Unsure what was happening, Captain Tsutsui decided they should continue fishing. Around 10 am, particles of pulverized coral dust began to rain down on the boat. The fallout – fine white flaky dust of calcinated Bikini Island coral, which had absorbed fission products and neutron-activated isotopes – was highly radioactive. It fell on the ship for three hours. The fishermen scooped the deadly dust into bags with their bare hands. One fisherman, Matashichi Oishi, reported that he “took a lick” of the dust that fell, describing it as gritty but with no taste. The dust stuck to surfaces, bodies and hair. Much later, after the radiation sickness symptoms began to appear, the fishermen called it “shi no hai”, the Death Ash.
Realizing their peril, the fishermen began to pull in the nets, a process that took a great deal of time. By the time they set off from the area, the Lucky Dragon’s deck was covered with a thick layer of fallout.
Very soon, the crew began to suffer from burns on their hands and faces, nausea, headaches, bleeding gums and eye pain. The fishermen, their catch of tuna and the Lucky Dragon herself, were all contaminated. When they reached Japan, biophysicist Yasushi Nishiwaki immediately travelled from Osaka to Yaizu to examine the crew and their boat. He quickly concluded that they had been exposed to radioactive fallout and wrote a letter to the chief of the US-AEC asking for more information on how to treat the crew. He needed to know what particular isotopes and atomic decay products to expect. But the US-AEC stonewalled him. In fact, the US government initially denied that the crew had radiation poisoning at all – a very insulting response to Japan’s doctors, who surely knew better than anyone what radiation poisoning looked like.
The Lucky Dragon crew were shifted to two top hospitals in Tokyo, where they spent many months. Treatment was experimental and recovery was slow. Chief radio operator Aikichi Kuboyama died, the first victim of a hydrogen bomb. He left these words: “I pray that I am the last victim of an atomic or hydrogen bomb.” The US did not respond to Dr Nishiwaki’s letter or to letters from other Japanese scientists requesting information and help, although they did dispatch two medical scientists to Japan to study the effects of fallout on the ship’s crew. The US government refused to disclose the fallout’s composition due to “national security”.
The insanity that was the nuclear arms race was to continue, with the US and the USSR each eventually acquiring enough megatonnage to destroy planet Earth six times over (although, as one wag remarked, it was unclear why they should need to destroy the planet more than once!)
Many more Hydrogen bomb tests were to take place – American tests at Bikini Atoll, nearby Eniwetok Atoll, and in the Nevada desert; Soviet tests at Novaya Zemlya, and in Kazakhstan, Uzbekistan, and Ukraine; and Chinese tests at Lop Nor, Mongolia – until the Complete Test Ban Treaty of 1996 (which North Korea, India and Pakistan have refused to sign). The destructive power of nuclear bombs was to increase until it reached the super-colossal yield of 50 megatons (the 26-foot long Tsar Bomba tested by the USSR at Novaya Zemlya in 1961). The Soviet Union eventually collapsed under the economic and political weight of its own armaments, taking with it the (perhaps misplaced) egalitarian dreams of many in the Third World.
The two Superpowers were immediately followed into the crazy nuclear labyrinth by Britain and France, later by China and Israel, and of course still later by India and Pakistan – but not by the only country that has suffered casualties to both nuclear and thermonuclear weapons.
The Japanese people and governments, despite having plentiful resources and being themselves among world technology leaders in the world, have not found it necessary to hurl threats of nuclear annihilation, in retaliation or otherwise, on their neighbours. So far, they have retained their maturity and their sanity.