Ah, the Bikini! What event more definitively announces that summer has arrived than the appearance of this classic swimsuit at beaches and poolsides across the world? An icon of women’s fashion, the bikini has permeated pop culture like few articles of clothing, giving us such lexical gems as bikini season, bikini bottom, and bikini wax. But while ubiquitous today, when first introduced in the summer of 1946, this skimpy swimsuit caused an outright scandal, and was banned in many places for decades. But this reaction was exactly what the bikini’s designer intended, for he named his creation after one of the most destructive and controversial events in human history. This is the explosive story of that event and how it resulted in the bikini we all know and love today.

If one defines “bikini” as a two-piece swimsuit that exposes the navel, then such garments have existed in one form or another since the dawn of human civilization, with the earliest known depiction – from the Çatalhöyük archaeological site in modern-day Turkey- dating all the way back to 5,600 B.C.E. Similarly, a mosaic in the fourth-century C.E. Villa Romana del Casale on Sicily depicts Roman women exercising in garments that look remarkably like modern bikinis, with bandeau tops and brief bottoms. However, the rise of Christianity brought with it stricter standards for women’s modesty, and such revealing swimsuits – and recreational swimming for women – all but disappeared from Western Europe for nearly 1500 years. It was not until the late 18th century, when “taking the waters” – whether in a lake, spring, or the ocean – became a popular cure for all manner of ailments, that female bathing finally became acceptable. And we do mean bathing as opposed to swimming, for the cumbersome bathing costumes of the day, made of heavy wool and featuring full-length sleeves, a knee-length skirt, and baggy bloomers, would quickly swamp and drown the wearer in anything but the calmest waters. Later, such costumes evolved into less cumbersome – and dangerous – flannel gowns fastened at the neck, but this in turn required stricter measures to preserve the bather’s modesty. Men and women’s beaches were usually segregated, while female bathers made use of elaborate contraptions known as bathing machines: wheeled huts that could be pulled from the beach into the surf by horses or men. After changing into her bathing costume, the bather would descend a staircase at the back of the machine into the water, where she could bathe shielded from view by a cloth awning known as a “modesty hood.” Meanwhile, a group of male attendants known as “dippers” stood on guard to ward off any lingering onlookers.

Over the following century, women’s bathing suits became simpler and restrictive, though they still featured full or half-length sleeves and pant legs and even short skirts. But this evolution took place in the face of stiff resistance, as Australian competitive swimmer Annette Kellermann discovered in 1907 when she was arrested at a beach in Boston. Her crime? Wearing a form-fitting but sleeveless one-piece swimsuit. Within a decade, however, such swimsuits had become the norm around the world, spurred in part by the introduction of women’s swimming at the 1912 Summer Olympics in Stockholm. A few years later, Danish-American designer Carl Jantzen, part owner of Portland Knitting Mills in Oregon, developed an elasticized rib-knit wool fabric perfect for making lightweight and form-fitting athletic singlets and swimsuits. The company, later renamed Jantzen Knitting Mills, would later adopt the slogan “The suit that changed bathing to swimming.”

Meanwhile, the emerging 1920s fad for sunbathing and the development of synthetic fabrics like rayon drove the introduction of increasingly revealing two-piece swimsuits. The rise of Hollywood further promoted the fashion, with two-piece swimsuits appearing prominently in such films as 1932’s Three on a Match and 1933’s Flying Down to Rio and Footlight Parade. While at first glance these suits were remarkably similar to modern bikinis, they were nowhere near as controversial for one simple reason: they kept the wearer’s navel covered. That’s right: while in the thirties cleavage and a bare midriff were A-Ok, the belly button was strictly verboten. Indeed, the 1934 Motion Picture Production

Code – better known as the Hays Code – included a strict prohibition on showing navels onscreen.

However, as is the case with so much social change, it was the demands of wartime that truly cemented the two-piece swimsuit as a fashion staple. Just as a shortage of steel during the First World War led women to abandon corsets for brassieres, the rationing of silk, rubber, and other strategic materials during the Second World War led the U.S. War Production Board to issue Regulation L-85, mandating a 10% reduction in the amount of fabric used in women’s beachwear. As a result, designers eliminated decorative elements like skirts and increased production of more economical two-piece swimsuits. Thus, when the war finally ended and Europeans were able to flock to the beach once more, the stage was set for an even greater revolution in swimsuit design – and for more on the impact of war on fashion, please check out our previous video How World War I Got Women to Wear Bras.

This revolutionary new swimsuit was developed simultaneously in 1946 by two French designers, Jacques Heim and Louis Réard, who were both trying to work around postwar fabric shortages. But while Heim’s design, which he dubbed l’Atome or “The Atom,” was skimpier than its 1930s and 40s predecessors, it still covered the wearer’s navel. Réard’s design, by contrast, truly pushed the boundaries of decency, comprising two triangles of newsprint fabric connected by strings to cover the breasts and another two covering the mons pubis and the buttocks. Recognizing that “like the [atom] bomb, [my design] is small and devastating,” Réard bestowed upon his creation a name that was just then dominating the headlines: Bikini.

Until 1946, very few people had ever heard of Bikini Atoll. Located in the Marshall Islands chain 3,000 kilometres southwest of Hawaii, the atoll consists of 23 coral islands surrounding a central lagoon 30 kilometres wide. For thousands of years Bikini was home to a few hundred Marshallese islanders, who sustained themselves by fishing and cultivating coconuts. In 1885 the atoll was annexed by the German Empire, who used it as a production hub for coconut oil. Then, in 1914, the Empire of Japan – at that time part of the Entente Powers – captured the Marshall Islands from the Germans and in 1920 was awarded the chain by the League of Nations as part of their South Seas Mandate. In 1941, following the outbreak of the Second World War in the Pacific, Japanese troops occupied Bikini in order to protect the nearby – and strategically vital – Kwajalein Atoll. Bikini remained in Japanese hands until February 1944 when, after fierce fighting, American forces recaptured Kwajalein. By this time, the garrison on Bikini consisted of only five men, who all chose to commit suicide by hand grenade rather than surrender.

And there the story might have ended, with Bikini remaining just another coral speck among hundreds in the gruelling American island-hopping campaign. But in December 1945, less than four months after the Japanese surrender, a decision was made that would catapult this once-obscure ring of islands into the global spotlight. While it was clear to all that the dropping of the atomic bombs on Hiroshima and Nagasaki in August 1945 had forever changed modern warfare, what was less clear was how exactly it had changed. As the Second World War gave way to the Cold War, military strategists began to wonder how best to use this awesome new weapon. Could it be deployed tactically on the battlefield, or was it only good for destroying civilian centres? And what kinds of targets was it most effective against? Particularly concerned about its role in the nascent atomic age was the U.S. Navy, which resented the Army Air Force’s monopoly on the delivery of nuclear weapons. The Air Force, meanwhile, argued that naval ships were extremely vulnerable to nuclear attack, and that the advent of such weapons had effectively made navies obsolete. Into this bitter dispute waded one Lewis Strauss, aide to Secretary of the Navy James Forrestal, future Chairman of the U.S. Atomic Energy Commission, – and, yes, the same guy played by Robert Downey Jr. in Oppenheimer. Strauss suggested staging a series of tests to evaluate the effects of nuclear weapons on naval vessels. “If such a test is not made,” Strauss argued:

“…there will be loose talk to the effect that the fleet is obsolete in the face of this new weapon and this will militate against appropriations to preserve a postwar Navy of the size now planned.”

Such a test had already been suggested several months before – though to a completely different end. In August 1945, Senator Brien McMahon, who would later write the Atomic Energy Act and chair the Congressional Joint Committee on Atomic Energy, publicly proposed using captured Imperial Japanese Navy ships to demonstrate the vulnerability of navies to – rather than their survivability against – nuclear weapons. Unsurprisingly, McMahon’s proposal was backed by United States Army Air Forces General Henry “Hap” Arnold, who was keen to prove that only the Air Force could be trusted with nuclear weapons. Both services thus pressed forward with their respective plans, with the Navy’s project being publicly announced on October 27, 1945 by Fleet Admiral Ernest King, Commander in Chief of the United States Fleet. As Assistant Secretary of War Howard C. Peterson later observed:

“To the public, the test looms as one in which the future of the Navy is at stake … if the Navy withstands [the tests] better than the public imagines it will, in the public mind the Navy will have ‘won.’”

To direct the tests, the Army initially recommended Major General Leslie Groves, the military director of the Manhattan Project which had developed the first atomic bombs. However, the Joint Chiefs of Staff decided that since the Navy would be contributing the majority of the men and resources, the tests should be run by a naval officer. They thus appointed Vice Admiral William H.P. Blandy, then Deputy Chief of Naval Operations, Special Weapons, to head the joint Army/Navy task force. Also on Blandy’s staff were Rear Admiral William S. Parson; Army Major Generals William E. Kepner and Anthony C. McAuliffe, and Technical Director Dr. R.A. Sawyer of the Los Alamos National Laboratory. Yet suspicion lingered in both military and civilian circles that the Navy would try to rig the tests to its own advantage, with Senator McMahon arguing that they should “[not be] solely responsible for conducting operations which might well indeed determine its very existence.” Faced with such accusations, Vice Admiral Blandy agreed to pack more target ships closer together than initially planned, and to the creation of a civilian committee to evaluate the final results. However, he rejected the Army’s demand that the ships be packed with fuel and ammunition, arguing that internal explosions could cause too many vessels to sink, preventing them from being studied after the tests.In January 1946, the plan, dubbed Operation Crossroads, was officially approved and announced by U.S. President Harry S. Truman. The operation had been named by Vice Admiral Blandy himself, who explained that:

“It was apparent that warfare, perhaps civilization itself, had been brought to a turning point by this revolutionary weapon.” 

And the site chosen to host the first nuclear explosions since Nagasaki was Bikini Atoll.

Almost immediately, Operation Crossroads drew severe criticism from all sides. Manhattan Project scientists, including scientific director J. Robert Oppenheimer, argued that such testing was unnecessary, and that the desired results could be more easily – and safely – obtained in the laboratory. Furthermore, they warned that detonating a nuclear weapon underwater would create a radioactive “witch’s brew” that could devastate the local environment. As a result, Oppenheimer declined an invitation to witness the tests, while the majority of his colleagues at Los Alamos stayed well clear of the Crossroads site. Others debated what the outcome of the tests would be, and whether atomic bombs were really viable as naval weapons. As an article in the March 16, 1946 edition of the Operation Crossroads Newsletter recounted:

“Armies and navies have been declared obsolete by laymen and scientists, and commentators, looking into the future, have pictured push-button wars, with man destroying himself in a matter of hours. On the other side, the Bomb has been declared over-rated. Dr. Phillip Morrison, Los Alamos scientist, said that the Bomb, if exploded in the air, would do little damage to the ships at Bikini, and Maj. Alexander P. Seversky, aviation expert, told the Senate Naval Affair Committee that he “wouldn’t mind being below deck” on the ship nearest the explosion.”

On the diplomatic front, politicians like Secretary of State James F. Byrnes and Secretary of Commerce Henry Wallace feared that Crossroads would anger the Soviets and scuttle the recently-proposed Acheson-Lilienthal Plan, which sought to place nuclear weapons under international control as a safeguard against future conflict. Indeed, many saw it as strangely hypocritical for the United States to pursue nuclear testing while simultaneously pushing for the abolition of nuclear weapons. In the words of ABC radio commentator Gram Swing:

“At Bikini, the Navy is preparing itself for the failure of the UN Atomic Energy Commission. On the one hand, we’re striving to rid the world of a weapon which may set back civilization for centuries…and on the other hand, we’re training ourselves in the use of this very weapon. So we strive to save civilization, and we learn how to wreck it, all on the same weekend.”

Hoping for more time to conclude negotiations, Byrnes urged President Truman to delay the tests by at least six weeks or – better yet – cancel them altogether. Truman agreed to the former, moving the date of the first test from May 15 to July 1. Officially, however, the delay was to allow more members of Congress to attend the tests during the summer recess.

Further objections came from animal rights groups – who protested the use of animals as radiological test subjects – as well as Congress, who questioned the wisdom of destroying $450 million worth of target ships. On the latter point, Vice Admiral Blandy countered that, being largely obsolete types, these ships were actually worth only around $3.7 million in scrap value.

Despite all this, Operation Crossroads went ahead as planned, and in February 1946 the survey ship USS Sumner arrived at Bikini and began blasting channels into the lagoon for the coming task force. Bikini Atoll had been chosen for a number of reasons, including its isolation, favourable weather, suitability as a sheltered anchorage, proximity to the Army Air Force base at Kwajalein, and its small population. As USS Sumner carried out its preparatory work, Commodore Benjamin Wyatt, military governor of the Marshall Islands, gathered the Bikini Islanders after their Sunday church service and asked them and their monarch, King Juda Kessibuki:

“Would you be willing to sacrifice your island for the welfare of all men?”

After a brief – if confused – discussion with his people, King Juda agreed, stating:

“If the United States government and the scientists of the world want to use our island and atoll for furthering development, which with God’s blessing will result in kindness and benefit to all mankind, my people will be pleased to go elsewhere. We will go believing that everything is in the hands of God.”

On March 7, the U.S. Navy evacuated all 167 Bikini Islanders to Rongerik Atoll, 216 kilometres away. Though they believed their relocation was temporary and that they would soon return home, history would have other plans. Meanwhile, Bikini was invaded by a massive armada comprising 242 ships, 156 aircraft, and more than 42,000 U.S. military and civilian personnel. In stark contrast to the intense secrecy surrounding the Trinity Test – the world’s first nuclear explosion conducted on July 16, 1945 – Operation Crossroads soon became the global media event of the year, acquiring an almost carnival-like atmosphere. Hundreds of civilian scientists from fifteen universities and several private companies were in attendance, as well as dozens of journalists from news outlets around the world. The majority of these were headquartered aboard the command ship USS Appalachian, which soon became known as the “press ship.” Initially, however, foreign observers were not invited, leading commentators like The Washington Post to object that “[the tests will] fortify the world’s fear that we think of the atom as our peculiar property and mean to brandish it as a weapon for our peculiar interests”. It was therefore decided at the last minute to invite two observers from each member of the UN Atomic Energy Commission: Australia, Brazil, Canada, China, Egypt, France, Mexico, the Netherlands, Poland, and the Soviet Union. Among these observers were physicists Simon Alexandrov and Chung-Yao Chao, who would go on to play key roles in the Soviet and Chinese nuclear programs, respectively.

As originally envisioned, Operation Crossroads comprised three different tests, codenamed Able, Baker, and Charlie after the Joint Army/Navy Radiotelephony Spelling Alphabet in use at the time. All three tests would use a version the same 23-kiloton Mark III “Fat Man” plutonium implosion device dropped on Nagasaki, with the Able device being airdropped on the target fleet by a Boeing B-29 Superfortress bomber, the Baker device detonated underwater in the atoll lagoon, and the Charlie device detonated in deeper water outside the lagoon. Two of the bombs were given nicknames by Navy personnel: the Able device being dubbed Gilda after the Rita Hayworth that came out that same year, and the Baker device Helen of Bikini.

Meanwhile, the target fleet comprised 95 vessels, making it the sixth-largest navy in the world at the time. The majority of these were obsolete or surplus U.S. Navy vessels, among which were the battleships Arkansas, New York, Nevada, and Pennsylvania, the cruisers Pensacola and Salt Lake City, the aircraft carriers Saratoga and Independence, as well as 16 destroyers, 8 submarines, and various other amphibious assault and auxiliary craft. Intriguingly, two of the battleships – Nevada and Pennsylvania – were survivors of the December 7, 1941 attack on Pearl Harbor which had drawn the United States into the Second World War. Having witnessed firsthand the revolutionary power of naval aviation, these old warhorses would now end their careers facing off against yet another game-changing weapon. Rounding out the target fleet were three vessels captured from the Axis powers: the Japanese battleship Nagato and light cruiser Sakawa and the German heavy cruiser Prinz Eugen. The symbolism of publicly annihilating these tokens of two defeated enemies was not lost on those in attendance; Operation Crossroads was many things, but subtle was not one of them.

The target ships were anchored in a roughly circular array 2 kilometres in diameter, 6 kilometres southeast of the main island of Bikini. At the centre of the array was USS Nevada, painted bright orange to serve as the aiming point for the bombardier. The ships were loaded with sample complements of fuel and ammunition, while some 25,000 scientific instruments including radiation detectors, pressure gauges, and both still and motion picture cameras, were arranged inside and outside the hulls, on the support ships anchored 35 kilometres away, and aboard instrumented aircraft circling overhead. Indeed, more than 9 million still images and 1.5 million feet of motion picture film would be shot over the course of the operation, accounting for nearly half the world’s supply of photographic material at the time. To gauge the biological effects of flash and radiation, 5,664 including 200 pigs, 200 mice, 60 guinea pigs, 204 goats, and 5,000 rats were penned above and belowdecks on 22 target ships. Some animals their fur shaved to simulate the effects on human skin, while others were dressed in standard Navy anti-flash clothing or smeared in anti-flash cream. In the wake of the detonations, remotely-operated drone aircraft including Grumman F6F Hellcats from the aircraft carrier USS Shangri-la and Boeing B-17 Flying Fortresses from Eniwetok Atoll would be flown through the mushroom cloud to collect radiation samples. It was, in other words, to be the largest and most well-documented scientific experiment in history.

Able day finally arrived on July 1, 1946. The B-29 Superfortress Dave’s Dream of the 509th Bombardment Group took off from Kwajalein and, at 9:00 AM local time, dropped Gilda onto the target fleet. The bomber, originally named Big Stink, had been the photographic aircraft on the Nagasaki mission but was renamed in honour of Dave Semple, a bombardier who was killed during a practice mission on March 7, 1946 – and for more on that often forgotten mission, please check our video Target Nagasaki: the Forgotten Story of Charles Sweeney and Bockscar on our sister channel Higher Learning.

Accompanied by a live radio countdown by Dr. Ernest Titterton, a British Manhattan Project physicist to later headed the British atomic bomb project, Gilda detonated at an altitude of 158 metres. After the blinding flash subsided, a giant orange brown mushroom cloud rose over the lagoon:

“For minutes the cloud stood solid and impressive, like some gigantic monument, over Bikini. Then finally the shearing of the winds at different altitudes began to tear it up into a weird zigzag pattern.”

As the smoke began to clear, all eyes turned to the target fleet. Yet despite the months of build-up and the apocalyptic images painted by Hiroshima and Nagasaki, the results of the Able test were decidedly anticlimactic. As Soviet observer Simon Alexandrov recalled:

“The only visible results from the air were two ships sunk and one on its side, plus four more ships burning….Everyone had the feeling that something had gone wrong.”

In fact, Gilda had missed its aiming point by nearly 650 metres. As a result, only five ships were sunk. Two attack transports, the USS Gillam and Carlisle, sank immediately; two destroyers, USS Anderson and Lamson, within hours; and the Japanese cruiser Sakawa the following day. The rest of the target fleet suffered only minor damage and were minimally contaminated by radiation, allowing them to be re-boarded within hours. Meanwhile, only around 10% of the test animals died immediately, while around 25% ultimately perished from the effects of radiation. The overall effect of the test was to rob the atomic bomb of much of the awe and mystique it had acquired in the public consciousness. As The Economist later observed:

“Dressed in all the trappings of an exaggerated and somewhat frivolous publicity, the first Bikini atom bomb experiment has left rather the impression of a fireworks display which slightly misfired.”

Time Magazine concurred, noting that:

“…[the bomb] had grown a little less awful as a result of Bikini. Its apparently infinite power was finite after all.”

Meanwhile, the Navy was delighted with the test, with Admiral Forrestal declaring that:

“…the American Navy will continue to be the most efficient, the most modern and the most powerful in the world”.

Unsurprisingly, the Navy was accused of rigging the test in its favour. However, a thorough investigation failed to determine the exact cause of the overshoot, with the most commonly accepted theory being that one of the bomb’s box fins collapsed as it fell towards the target.

But while the Able detonation made the atomic bomb look like something of a damp squib, Baker would reveal the weapon’s true destructive potential and yield some of the most iconic and enduring images of the nuclear age. For this test, Helen of Bikini, identical to Gilda in design and yield, was suspended 27 metres beneath the target fleet from the amphibious assault ship LSM-60. Detonated at 8:35 AM on July 25, the Baker shot produced a unique, awesome spectacle unlike anything seen before or since. As New York Times correspondent William Laurence wrote:

“For a time it looked as though a giant mountain had risen from the sea, as though we were watching the formation of a continent…and then it took the shape of a giant chain of mountains, covered with snow, glistening in the sun”.

Major General Nichols of Vice Admiral Blandy’s staff also described the awesome spectacle:

“Niagara Falls in reverse shot up over an area fully 2,200 feet in diameter, millions of tons of water rose about 5,000 feet and finally vapour and steam came out on top. As the tons of water came tumbling back into the lagoon, what appeared like a tremendous breaking wave broke out of the mass of water and advanced towards the next circle of target ships.”

Still and moving images of the test reveal the sheer scale of the explosion, with even battleships like Nagato and Nevada looking like toy boats next to the gargantuan, cauliflower-shaped water column thrown up by the bomb. The underwater blast proved far more effective than the Able airburst, completely vaporizing LSM-60, displacing 2 million tons of water, and creating a tsunami that immediately sank the battleship USS Arkansas, the submarines USS Pilotfish, Apogon, and Skipjack, and the concrete yard oiler YO-160. Contrary to popular belief, Arkansas was not lifted vertically by the blast; the dark, vertical object seen in many pictures of the Baker water column is merely a gap produced by Arkansas’s superstructure. Instead, the shock wave and tsunami completely sheared off said superstructure and rolled Arkansas onto its back, whereupon the battleship immediately flooded and sank to the bottom of the lagoon.

But while the remaining target ships were not immediately sunk, many were severely damaged, suffering massive leaks that threatened to sink them within hours. But when Navy crews re-boarded the ships to assess and repair the damage, they discovered a far more serious problem: the hulls were dangerously radioactive. As the Manhattan Project scientists had predicted, the underwater detonation had contaminated the water with a witch’s brew of fission products and unconsumed plutonium, which washed over the ships as a 270-metre tall “base surge” when the water column fell back to earth. So extensive was the contamination that many ships could not be safely approached, and several, including the aircraft carrier USS Saratoga and the Japanese battleship Nagato, sank before their hulls could be repaired. In all, 14 ships sank as a direct result of the blast.

Meanwhile, the other ships proved nearly impossible to decontaminate – either by scrubbing with soap and water or sandblasting paint off metal surfaces. And while decontamination crews were limited to shifts of no more than a few minutes, few were issued any kind of protective equipment, and many suffered from acute radiation sickness and long-term health issues like cancer. The vast majority of the test animals -mainly pigs and rats – also died within a few days of the test. And while Vice Admiral Blandy reassured the public that the animals died painlessly, he almost certainly knew that this was a lie – and for more on this horrifying subject, please check out our previous video Tickling the Dragon’s Tail: the Horrible Heart of a Nuclear Bomb.

Within two months of the Baker shot, the radiation had sufficiently decayed for some of the larger ships to be towed away for further study. USS Pennsylvania and the German cruiser Prinz Eugen were taken to Kwajalein, USS Nevada and New York to Pearl Harbor, Hawaii, and USS Independence to Hunters Point Naval Shipyard in San Fransisco. Due to severe contamination, a minor leak aboard Prinz Eugen went undetected, and on December 22, 1946 she capsized in shallow water where she remains to this day. Efforts to decontaminate the remaining ships proved unsatisfactory, and by 1951 all were decommissioned and scuttled in deep water.

The extent of the contamination wrought by Crossroads Baker caught the U.S. Navy completely by surprise, revealing that the greatest threat posed by nuclear weapons was not blast or tsunamis but radiation, which would instantly render any ship uninhabitable. But the contamination was not limited to the target fleet or even the Bikini lagoon; the base surge rendered the main island of Bikini uninhabitable for a week, while radioactive vapour drifted east over Rongelap and Rongerik Atolls, where the Bikini Islanders had been relocated. It was an ominous sign of things to come. The test also produced serious fallout of the political kind. As Secretary of State James Byrnes had feared, the Soviets ultimately rejected an updated version of Acheson-Lilienthal Plan known as the Baruch Plan, and dream of achieving international control of nuclear weapons fell apart. Three years later the Soviets detonated their first atomic bomb, ending the United States’ nuclear monopoly and pushing the Cold War into a dangerous new phase.

Shortly after the Baker shot, it was decided to cancel the third planned deep-water test, codenamed Charlie. While this decision largely stemmed from the Navy’s inability to decontaminate the remaining target ships, the Army also argued that using up the nation’s tiny nuclear stockpile in testing was impeding efforts to develop smaller, more efficient nuclear weapons. The scientific objectives of shot Charlie would eventually be achieved on May 14, 1955 during Operation Wigwam, conducted 800 kilometres southwest of San Diego. A 30-kiloton Mark 90 “Betty” nuclear depth charge was detonated at a depth of 610 metres, with instrumented miniature submarine hulls known as Squaws being used to gauge the effects.

With Operation Crossroads officially over, on November 7, 1946 a reception was held in honour of Vice Admiral Blandy, during which he and his wife were photographed cutting into a cake shaped like a mushroom cloud. The photograph sparked outrage, with Reverend A. Powell Davis of Washington, D.C. declaring in a fiery sermon:

“If I had the authority of a priest of the Middle Ages, I would call down the wrath of God upon such an obscenity. I would damn to hell these people of callous conscience, these traitors to humanity.”

Indeed, Blandy and his staff were faced with a difficult public relations situation. Though originally intended to allay public fears about nuclear weapons and demonstrate the invulnerability of the U.S. Navy, Operation Crossroads had achieved just the opposite, stoking nuclear malaise to an all-time high. Indeed, a 1947 report on the tests in Life Magazine informed viewers that:

“If all the ships at Bikini had been fully manned, the Baker Day bomb would have killed 35,000 crewmen. If such a bomb were dropped below New York’s Battery in a stiff south wind, 2 million people would die.”

In an attempt to save face, Vice Admiral Blandy declared that any target ship which sank more than 10 days after the Baker shot would not be considered to have been sunk by the bomb. Thus, even though all but 9 of the 97 target ships were either sunk or rendered too radioactive to even be sold for scrap, the official Navy report listed only 19 ships sunk between two tests. But they needn’t have bothered with this fudging, for despite postwar fears the Navy was not rendered obsolete and received a significant portion of the U.S. defence budget throughout the cold war period.

After the conclusion of Operation Crossroads, the US military temporarily abandoned Bikini as a nuclear testing site, largely due to the inability to build on the atoll. However, in March 1954, the atoll was chosen for Operation Castle, the first test of a practical thermonuclear or hydrogen bomb. Like the Crossroads Baker shot, the Castle Bravo detonation of March 1, 1954 created far more fallout than anticipated, contaminating large swathes of the South Pacific and triggering an international incident – and for more on this, please check out our previous video Who Invented the Hydrogen Bomb. In total, the United States would conduct 23 nuclear tests on Bikini Atoll between 1946 and 1958.

Meanwhile, the relocation of the 167 Bikini Islanders had to Rongerik Atoll had failed due to the island’s inferior climate and productivity. Thus, after several months of starvation and hardship, the islanders were moved to Kwajalein Atoll. In 1970, Bikini Atoll was finally declared safe for human habitation and the islanders allowed to return. However, less than a decade later it was found that levels of Caesium-137 and in the islanders’ bodies had increased by 75%, the isotope having become concentrated in coconut palms and other common food plants. As a result, in 1978 the Bikini Islanders were evacuated once again – this time to Kili Island. Their descendants remain there to this day, waiting for the day when they can finally return to their traditional home.

It was against this explosive background that Louis Réard launched his bold new swimsuit design he named the “bikini”. The first modern bikini was introduced on July 5, 1946 – just 4 days after the Crossroads Able test – at a popular Paris pool called Piscine Molitor. So revealing was Réard’s creation that no model in Paris would agree to wear it. Réard was thus forced to hire 18-year old Micheline Bernadini, an exotic dancer at the Casino de Paris. Like the Crossroads Baker detonation, the bikini made an enormous splash, with American fashion writer Diana Vreeland declaring it “the atom bomb of fashion” and Bernardini receiving more than 50,000 fan letters. Yet despite some initial shock, the French public largely took the bikini in stride, with the newspaper Le Figaro explaining that:

“People were craving the simple pleasures of the sea and the sun. For women, wearing a bikini signaled a kind of second liberation. There was really nothing sexual about this. It was instead a celebration of freedom and a return to the joys in life.”

Others, however, were less forward-thinking. In 1950, American swimsuit designer Fred Cole decried the bikini as:

“…a two-piece bathing suit which reveals everything about a girl except for her mother’s maiden name.”

While in 1957 Modern Girl Magazine declared:

“It is hardly necessary to waste words over the so-called bikini since it is inconceivable that any girl with tact and decency would ever wear such a thing”.

The bikini was condemned by Pope Pius XII and American National Legion of Decency, while wearing the swimsuit in public was banned on the French Atlantic coast as well as in Belgium, Italy, Portugal, Spain, Australia, and many other countries. In response to this moral outrage, Réard’s rival Jacques Heim emphasized the more conservative cut of his atome swimsuit. Réard, by contrast, leaned into the controversy, declaring that a swimsuit couldn’t be called a bikini unless it could be pulled through a wedding ring.

But as with the transition from one to two-piece swimsuits, it was Hollywood which truly turned the bikini into a fashion staple. Throughout the 1950s, popular actresses and sex symbols like Ava Gardner, Rita Hayworth, Marylin Monroe, Esther Williams, and Betty Grable took advantage of the controversy surrounding the bikini to sell millions of risqué swimsuit pinup shots. Feature films such as 1952’s Manina, the Girl in the Bikini, 1962’s Dr. No, 1963’s Beach Party, and 1966’s One Million Years B.C., which featuring bikini-clad leading ladies Brigitte Bardot, Ursula Andress, Annette Funicello, and Raquel Welch, further served to legitimize the style in the popular imagination – as did songs like the 1960 Brian Hyland hit “Itsy Bitsy Teenie Weenie Yellow Polka Dot Bikini” and the Sports Illustrated Swimsuit Issue, which made its debut in 1964. By 1965, the once scandalous bikini had become fully mainstream. Today, the bikini is so ubiquitous that the original apocalyptic connotations of the name have been all but forgotten. Once synonymous with the anxieties of the nuclear age, today the word largely evokes images of another kind of bombshell…

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