Will a Nuclear Weapon Ever Be Fired Again?

It's been 75 years since the world's first nuclear bomb was dropped, wiping out half of the population of Hiroshima, a city in Japan.

In the unprecedented event, which took place at 8.15am local time on August 6, 1945, American pilots aboard a US B-29 bomber unleashed the equivalent of 12,500 tons of TNT in a bomb that was more than 2,000 times as powerful as the largest bomb ever used before.

But what has changed in the last 75 years? What have the lessons of the end of World War II taught modern leaders about the dangers of nuclear power? And do the images from that fateful day in 1945 mean nobody will be willing to use them ever again?

The atom bomb in 1945, nicknamed "Little Boy", reached temperatures of several million degrees at its burst-point above Hiroshima, killing 80,000 people instantly, but also causing long-term illness and disability for those who had survived the immediate blast but who subsequently became ill due to the radiation.

On August 9, a second atom bomb, nicknamed "Fat Man" was dropped on the city of Nagasaki, killing 40,000 people immediately, with tens of thousands of others dying in the aftermath.

In total, it is estimated that 140,000 people out of a population of 350,000 died in Hiroshima, with 74,000 being killed in Nagasaki.

Although the war in Europe had concluded in May 1945, it had continued in the Pacific theatre. The dropping of the two atom bombs is credited by many historians with bringing the war to an end.

The use of the atom bombs not only had an immediate impact on Japan itself but cast a much longer shadow for decades to come on the nature of conflict. That long shadow is as relevant today as it ever has been.

Some survivors fear that President Trump's current policies could bring about new nuclear attacks, as suggestions of a new Cold War between the U.S. and both China and Russia.

Professor Rana Mitter, of Oxford University, who specializes in the history of China and Japan says the use of the atom bombs had a profound impact not only on how Japan viewed nuclear weapons but also across the world.

Hiroshima was nearly entirely destroyed in 1945
The wrecked framework of Hiroshima's Museum of Science and Industry as it appeared shortly after the blast. Getty

He told Newsweek: "The Japanese have an even more heightened hostility to nuclear weapons than any other society on earth for the perfectly logical reason that they're the only people to date, and we hope permanently, who have actually had atomic weapons used against them.

"Anti-nuclear culture has become quite central to the self-image and the self-presentation to the wider world of Japan, even when other aspects of culture are probably what you would call 'conservative'."

"The Hiroshima and Nagasaki atomic bombings are one of the turning points for humanity. The devastating nature of atomic weapons was something quite different from anything that humans had ever seen previously."

Some have questioned whether after knowing the full extent of the devastation and destruction caused by nuclear weapons, any state would ever use them again.

Professor Alex Wellerstein, a historian of science at the Stevens Institute of Technology who studies the history of nuclear weapons, says that since the events of Hiroshima and Nagasaki, there have been two overarching reasons why nuclear weapons have never been used again.

"The rational answer is having them as deterrents, not wanting to normalize the use of these weapons for good, strong reasons," Prof. Wellerstein said.

"There are also a lot of scholars identifying with more emotional reasons, more irrational reasons: the development of the nuclear taboo, the idea that you can't use nuclear weapons because it's a moral problem, not because it's some sort of rational thing, but because it's just the 'wrong' thing to do."

Prof. Wellerstein says that the taboo around nuclear weapons, which viewed them as morally problematic, took a while to develop across the world.

"The American military didn't tend to see the atomic bomb as being a new moral question, they just thought of it as an expedient means to a certain type of ends. Maybe you would use them tactically, maybe you use them against cities if you needed to end the wars quickly."

Prof. Wellerstein says that the person who has the strongest emotional reaction to the use of the atom bombs after discovering the full extent and scale of civilian casualties was President Truman, who had supported the use of the bomb.

"On August 10 after Nagasaki, Truman tells the military that they are not allowed to use nuclear weapons without his explicit permission, he tells his cabinet this because he couldn't imagine killing another 100,000 people", says Professor Wellerstein.

"He has a real aversion to using nuclear weapons again."

Historians have continued to debate whether the use of the atom bombs 75 years ago was really necessary and if Japan would have surrendered anyway.

"It's immensely complex", says Professor Mitter.

"It is very difficult to give a precise answer as to who knew what and when in the Japanese high command.

"There is certainly evidence that some elements of the Japanese leadership after the atomic bombings wished to surrender. There is also some evidence that there were other elements that might have carried on fighting, going against the orders of the top command even after the atomic bombings.

"It's also a question of whether or not the Soviet attack on Manchuria, the other major event of that period, would really have made such a monumental difference to the ending of the war in Asia.

"One thing you can say at the time is that China, the single major allied Asian power fighting against the Japanese, did not express at that time any regret about the atomic bombings whatsoever, the Chinese felt that it was something that bought the war to an end much more quickly than otherwise might have happened."

Prof. Wellerstein expresses a similar view to that of Professor Mitter and asks what other alternatives the U.S. had at the time, questioning the assumption that a major U.S. priority was to minimize civilian casualties.

Professor Wellerstein says that U.S. officials saw using the atom bombs as a "good thing across the board."

He told Newsweek that the use of the atom bomb cemented America's belief in its military superiority.

"Americans since then have believed that technological superiority would translate into military superiority and what we've found, if you look at American conflicts since 1945, is it's not that simple, there's a lot that goes on into who wins a conflict," he said.

"Technology plays a role but so does ideology, knowing the home terrain, so does the public perception, both at home and abroad of the sort of moral rectitude.

"The U.S. has found itself over and over again, getting involved in conflicts that military leaders say will be resolved really fast because we have more tech than the people we're involved with and it turns out that things can drag on a very long time."

In some quarters, there's a growing belief that nuclear weapons will never be used again, not only because of the destruction they cause but also over the calculation that the use of nuclear weapons by two nuclear-armed states would result in the complete annihilation of both the attacker and defender, otherwise known as the concept of "mutually assured destruction (MAD).

For example, current nuclear weapons are over 50 times more powerful than the bomb dropped on Hiroshima, as shown in this graphic provided by Statista.

Nuclear weapons in 1945 and 2020 compared
Nuclear weapons are now much more powerful, as shown in this Statista graphic Statista

It's this complacency and the false sense of security that Prof. Mitter warns against: "During the Cold War, many societies developed a culture in which they understood the terrifying devastating power of nuclear weapons.

"It sometimes seems that in the post-Cold War era, countries have forgotten quite how devastating such an attack would be and if there is a danger of the use of nuclear weapons in the present day, it will come from societies that have been foolish enough to forget quite how horrific the effects and after-effects are."

Professor Mitter says the bombings had a profound effect on Japan.

"[The atom bomb] turned Japan into a country, which in some ways like Germany, found the strong sense that it could not go to war again, not just nuclear war but war of any sort. A much stronger part of the public culture than with many other comparable countries."

Professor Wellerstein doesn't think it'd be a wise move to bet that those with nuclear weapons are "only bluffing".

He said: "Is it just a bluff? Whether it's a bluff or real possibility will depend on the specific people who are in the position to actually make the order to go forward and depending on your country that might be one or two people at most.

"I always tell people, if we're talking about lots of people, it's pretty easy to generalize what they're thinking. I can tell you what 80 percent of the population would do in a certain situation, but I can't tell you what one person is going to do in that situation, based on their background, their history, their mood that day, the effect of medications they might be on their mental states."

Nine countries have current nuclear capabilities and experts have told Newsweek that a "new arms race" is underway.

The U.S. and U.K. have different protocols when it comes to the launch and use of nuclear weapons.

The U.S. president has the sole authority to call a nuclear strike. After he decides to make the call, the procedure dictates that he should meet with top military advisers in the Situation Room of the White House or via a secure line if the president is not present.

The president's order is then verified, through a challenge code read to the president. He then receives the "biscuit", a laminated card that has the matching response to the challenge code.

It is then left to the Pentagon to send an encrypted message to missile crews which includes the war plan as well as the missile launch codes.

The missiles are launched by missile crews turning their keys at the same time.

In the U.K., only the prime minister can authorize a nuclear strike. Such an order is sent to one of Britain's nuclear submarines with a special set of codes.

In the event that a nuclear strike has destroyed the British government, including the prime minister and the "second person", which normally includes a high raking cabinet officer such as the deputy prime minister, the letters of last resort are opened.

Written when a prime minister takes office, the four identically worded handwritten letters are given to the commanding officers of the four British ballistic missile submarines, containing options such as retaliating with nuclear weapons, not retaliating, or placing the submarine under an allied country's command.

The contents of the letter remain unknown, as they are destroyed unopened when a prime minister leaves office.

So will a nuclear weapon ever be fired again?

Nobody we spoke to is willing to say for sure.