“When I level out, the nose is a little bit high and as I look up there the whole sky is lit up in the prettiest blues and pinks I’ve ever seen in my life. It was just great.”

The view from the ground, about nine kilometres below from where pilot Paul Tibbets gaped at colours in the sky, was anything but.

“One of our classmates had fallen into the pool”, Kataoka Osamu, then a teenage schoolboy, recalled, “he was already dead, his entire body burned and tattered. Another was trying to extinguish the flames rising from his friend’s clothes with the blood which spurted out of his own wounds. Some jumped into the swimming pool to extinguish their burning clothes, only to drown because their terribly burned limbs were useless. There were others with burns all over their bodies whose faces were swollen to two to three times their normal size, so they were no longer recognizable. I cannot forget the sight of those who could not move at all, who simply looked up at the sky, saying over and over, ‘Damn you! Damn you!’ ”

Hiroshima had been preparing for a day like this for months. By 1945, attacks by US bombers on Japanese cities had become commonplace. Hiroshima had been spared till now but, as a thriving hub of manufacturing and military activity, was on high alert. School children had been mobilised to demolish homes along city corridors to create firebreaks. The aim was to prevent firestorms of the kind which devastated Tokyo. A single night-time raid on Japan’s capital by nearly 300 US B29s killed about 100,000 people.

When air raid sirens broke the morning calm of 6 August 1945, the people of Hiroshima did not panic. Air defence spotters reported only two or three B29s approaching the city. Hardly a mass raid; not enough to induce terror in a population habituated to war. People went about their business.

It was probably only a matter of seconds after “Little Boy” – the atomic bomb dropped from the approaching B29 flown by Colonel Tibbets – exploded 600m above Shima Hospital that those who survived the initial blast and heat wave realised that, in fact, they could never have prepared for a day like this. History hadn’t known one. Little Boy was 6,500 times more efficient at killing than a regular bomb.

***

The United States began developing the atomic bomb as a national project at the outbreak of World War II. Unprecedented effort, manpower and money were expended to build a weapon of unimaginable destructive power. Two types of atomic bombs were eventually produced – a uranium bomb, which was dropped on Hiroshima; and a plutonium bomb (“Fat Man”), dropped three days later on Nagasaki.

The project was launched in 1939 after a small group of refugees from Europe, mainly Jewish physicists – Nobel Prize winners, including Albert Einstein, among them – warned US leaders that Nazi Germany was developing a programme to build atomic weapons. A year earlier, German chemist Otto Hahn had discovered nuclear fission. Scientists everywhere understood that the energy released from fission could – theoretically – produce a nuclear explosion.

Perhaps the largest technological endeavour in human history, code-named the Manhattan Project, was birthed by a singular fear: that Hitler would get his hands on the bomb before the US did.

Nothing about how Little Boy came into being – the characters and places, the scale of ambition, the ethical dilemmas evoked, its impact on history – is diminishable. Whole libraries could be devoted to this story. Many writers have tried to elide its moral complexities, sculpt cause-and-effect around its every turn, answer every question. Their books are best left on the shelf.

***

During the final, apocalyptic months of World War II, once-unthinkable acts were routinely justified on all sides. Whatever their private thoughts, leaders knowingly killed their enemies’ civilians in large numbers.

We know that then US President Harry Truman believed that dropping the bomb would compel Japan to surrender and, ultimately, save more American and Japanese lives by avoiding a land invasion of Japan. But we will never know if more lives were saved; if Japan would have buckled under more conventional bombing, as Truman’s successor, Dwight Eisenhower, argued at the time; or if it was the entry of the Soviet Union into the war against Japan on 8 August, rather than the attacks on Hiroshima and Nagasaki, that was more decisive in forcing Japan’s surrender. 

We also know that the scientists and engineers working on the Manhattan Project suffered doubts, which for many gave way to remorse in the years and decades after Hiroshima. One of its leading physicists, Luis Alvarez, spoke for many of his colleagues in a letter to his young son, written aboard one of the B29s accompanying Tibbets, from where Alvarez watched Little Boy explode:

“…what regrets I have about being party to the killing and maiming of thousands of Japanese civilians this morning is tempered with the hope that this terrible weapon we have created may bring the countries of the world together and prevent future wars.”

Alvarez’s boss, J Robert Oppenheimer, often called ‘the father of the atomic bomb’, similarly thought that it is “not only a great peril but a great hope”. They were less forthright in admitting that by bringing this terrible weapon to life, there was little prospect that it would not be used. By the end of 1942, German research lost steam and Hitler effectively withdrew from the nuclear race with the US. The Allied victory in Europe in early May 1945 further rendered Manhattan’s raison d’être obsolete. The bomb became a solution looking for a problem – a means searching for an end to justify its existence. Japan became that end.

Tibbets might have been expected to have deeper misgivings than Alvarez, after the carnage inflicted on Hiroshima became known. Alvarez knew infinitely more about the destructive power of Little Boy than those charged with dropping it. Tibbets was given many chances to express regret before he died in 2007. Not once did he oblige. His soul remained untroubled in the knowledge that he did what he was told; an act both patriotic and merciful. It “saved a lot of lives”, he said time and again in interviews. Yet Tibbets knew as well as Einstein, Oppenheimer and Alvarez that Little Boy changed the world forever. Before his passing, Tibbets requested that his remains be cremated and that no monument to him be built. He feared that future generations may gather there, to rail against the bomb.

Of the 78,000 buildings standing in the city that August morning, nearly 50,000 were totally incinerated. Almost all the rest were partially destroyed. About 80,000 of Hiroshima’s estimated population of 350,000 in 1945 were killed instantly. People within 800m of the blast were turned into lumps of charcoal by the heat wave. Another 80,000 or more people living in the city at the time would die in the coming weeks, months and years, due to the effects of burns or radiation. The exact number will never be known.

***

Alvarez got one thing (mostly) right in his letter to his son: the unfathomable nightmare visited upon Hiroshima would help prevent future wars. But only between countries that had the bomb. Peace between them would obtain in knowing that they could annihilate each other, whomever struck first. The idea seemed mad, literally: Mutual Assured Destruction (MAD).

More than 70,000 nuclear warheads would be built over the next four decades, mostly by the US and Russia. Ever-more lethal and ingeniously deployed – as missiles, torpedoes, land mines, artillery shells – the bomb gave a perverse order to the post-War era. To protect their interests, major powers developed their own arsenals. A seat at the top table demanded it. They would internalise the logic of nuclear deterrence, but only for them. Lesser nations had to accept another reality, expressed in a global agreement signed in 1970, the Nuclear Non-Proliferation Treaty (NPT): states already possessing nuclear weapons would get to keep theirs but no one else would be permitted to get them. The deal was anchored in two promises: if they stuck to the rules, the nuclear have-nots could benefit from the peaceful uses of nuclear energy; and secondly, the haves would make genuine steps towards getting rid of their nuclear weapons. The former promise has been broadly kept. Not so much the latter.

One of the great tragedies of modern times is that Hiroshima has not reshaped our world for the better. Rather, it has locked us into the Cold War’s icy covenant: as the price of being “protected” by an (untested) deterrent, we must accept being held hostage to the prospect of nuclear catastrophe, without hope of relief, affecting generation after generation. The pact feels less demoralising than it once did. Terrorism, climate change, now global pandemics haunt us more these days. But the ghost of Hiroshima has not moved on. 

Perhaps the only time it might have done so was 1986, during a weekend meeting in Iceland of all places, between then US president Ronald Reagan and Soviet leader Mikhail Gorbachev. The great nuclear adversaries stared into the abyss and concluded that the world needn’t fall into it. Proposals put forward at the Reykjavik Summit for swift and total global nuclear disarmament were so radical that both Russian and American aides scrambled to rein in their leaders, knowing that once off the island, they’d face mountains of obstacles. Sure enough, it was a dream deferred. But in the simple act of imagining it, Reagan and Gorbachev made the world a safer place, offering a glimpse of what a post-Cold War world might look like.

History has not been kind to their vision. 

***

The global store of nuclear weapons has decreased dramatically since the 1980s. Today there are less than 14,000 in existence, mostly still held by the United States and Russia, with the rest shared between China, the United Kingdom, France, India, Pakistan, Israel and North Korea. (South Africa remains the only country to develop and then voluntarily dismantle its nuclear arsenal.)

No one should find comfort in these numbers. Nuclear powers are modernising their arsenals and developing new technologies to support them. Evidence that they are losing faith in the bomb’s political and military value is scarce. What is clear is that nuclear weapons have become almost immeasurably more powerful since Hiroshima. A simulation of the 500 kiloton “Ivy King”, the largest pure fission bomb ever tested by the US (Little Boy exploded with about 13 kilotons of force), exploding over London generated a terrifyingly precise death toll of 453,370 people. Russia tested a thermonuclear weapon – which gets its explosive power mainly from fusion – in the high Arctic that had an explosive yield equivalent to 3,000 bombs of the kind dropped on Nagasaki. That test was nearly 60 years ago.

I have never been able to get my head around one sentence from How to Build a Nuclear Bomb, a portentous book by British nuclear physicist and peace scholar, Frank Barnaby, published in 2004:

“There is no critical mass for the fusion process, and so in theory there is no limit to the explosive power that can be obtained from a thermonuclear weapon.”

What cruel joke we play on ourselves, pretending that such destructive power is securely tucked away, forever. International trust – if that can be measured – in all but a few of the current crop of men leading nuclear-armed states is pitifully low. In the past, my own Western biases would have led me to expect a US president, at least, to be prudent in times of grave crisis. That was before Donald Trump said he wanted to be “unpredictable” with nuclear weapons, which he later speculated could be used to “stop hurricanes from hitting the United States”.

In the heady days after the collapse of the Berlin Wall, whatever justifications nations had for building nuclear weapons seemed to be melting away. Hanging on to them for reasons of influence or prestige, or to deter enemies who were fast becoming friends, no longer seemed defensible. But historical moments are just that – moments. They tend not to last long. Great power relations are so different today that one could be forgiven for thinking that that moment never happened. 

Covid-19 has surely refined our sense of the unthinkable. For decades we have assumed, despite the occasional scare, that nuclear weapons will never be used in anger again. It is an assumption so tightly threaded into the global consciousness that we often forget that the bomb even exists.

None of us wants to see a mushroom cloud again. But we seem to have lost the will to think anew about nuclear weapons. Seventy-five years on from that August morning in Hiroshima, humanity seems neither wiser nor more foolish about the bomb. Just spiritless. DM

Dr Terence McNamee is based in Johannesburg and is a Global Fellow of the Wilson Center (Washington, DC). He is the co-Editor of The State of Peacebuilding in Africa (Palgrave, 2020)