Until recently, a significant taboo has existed around the use of nuclear weapons in war. However, we are now in a position where that taboo is being flagrantly disregarded by the leaders of the most powerful nation in the world, and a totalitarian dictatorship.

Taboos offer a way for us to create overarching rules of societal acceptability that transcend our social and cultural norms. Taboos prohibit behaviours that are not appropriate within and beyond the moral or ethical framework of an individual community – scenarios that are so dangerous or perverse that they are almost unspeakable. Traditionally, those who engage in taboo activities, such as incest, are stigmatised and ostracised by their society, as their breach or defiance of taboo could have significant and unacceptable repercussions. We had a taboo surrounding deploying nuclear weapons – out of respect for the devastation they can wreak – but it seems more and more fragile.

Fat Man and Little Boy exploded in the skies over Nagasaki and Hiroshima 72 years ago. The immediate consequences of the bombings were dramatic and survivors of this attack are still physically, culturally and psychologically affected by their experiences to this day. This is the source of the nuclear taboo.

It evolved during the cold war, as our international arsenal transitioned from atomic bombs to larger and more devastating thermonuclear weapons. These were tested in seemingly endless competitive escalation by the first five nuclear states, Russia, France, the USA, China and the UK.

In 1960, Herman Khan of the Rand Corporation arrived upon the idea of Mutually Assured Destruction (MAD) as a reason to inhibit further weapon development. He declared that nuclear defence technologies had grown to such enormous proportions that it would now be possible to obliterate humankind if multilateral nuclear warfare was ever undertaken. Whereas the initial era of nuclear arms development created a frenzied, normalised, and even valorised race toward weapons development and deployment, MAD subsequently stigmatised and reversed those goals, firmly establishing the nuclear taboo. Despite the taboo, testing and development continued among non-nuclear states, including Pakistan and India. However, the Comprehensive Nuclear Test Ban Treaty of 1996 cooled hostile interactions between nuclear weapon possessor states. For about a decade or so, we felt comparatively safe from nuclear warfare.

The conscience of the world had stigmatised nuclear weapons – and the taboo of MAD had stretched far beyond the geopolitical arena and the strategic concerns of individual states by the end of the Cold War. Public disquiet was multifaceted and complex. State nuclear strike preparedness activities, such as Protect and Survive in the UK, had been counterproductive and created further apprehension. Passionate appeals from the Hiroshima and Nagasaki atomic bomb survivors emphasised the brutal nature of the bomb, and further contributions to the growth of stigma were made by the women of Greenham Common and other anti-nuclear movements. A shift in attitudes meant that nuclear weapons had gained a special status, inhumane and uncivilised. Even President Ronald Reagan recognised the stigma of nuclear weapons during the Cold War, saying that “A nuclear war cannot be won and must never be fought. The only value in our two nations possessing nuclear weapons is to make sure they will never be used.” His thoughts were echoed by UK Prime Minister Margaret Thatcher and Russian President Mikhail Gorbachev during the 1980s. How and why have we entered a new phase of nuclear brinkmanship?

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Thanks to President Donald Trump and Supreme Leader Kim Jong-Un, our generation’s own volatile Fat Man and Little Boy, the sensible norms of restraint and careful diplomacy that have previously surrounded nuclear deterrence proliferation and use are now under stress. President Donald Trump seems indifferent to social norms, and behaves without rationality. He made several public statements, via Twitter and traditional media, that glamorise the use and increased production of nuclear weapons. All while his administration slashes budgets and slashes programs designed to protect communities from the well-documented risks that come from producing nuclear weapons. Trump has ostracized himself from international leadership nearly every turn, including NATO and G-20 summits, isolating himself from democratic world leaders, and aligning himself more with leaders of totalitarian and authoritarian regimes. He has divided America, twisting the knife into historical wounds of racism and civil rights abuses, as well as upending environmental protection, denying climate change and proposing a tax regime that will create persistent poverty – to name a few examples.

North Korea is currently basking in its own nuclear disruption, finally gaining the place that it feels it deserves in the geopolitical arena – for all the wrong reasons. Like a child who learns to gain attention for bad behaviour, Kim relishes this moment. However, there is a tragic legacy behind his trumped-up attempts at power. Poverty and human rights violations are experienced by many North Koreans, and there is a dark legacy of Eisenhower’s Atoms for Peace programme that originally took nuclear technology to South East Asia in the hopeful 1960s. We mustn’t forget the human beings who live in North Korea, and the way that UN sanctions are already affecting their lives.

The bickering across Twitter has escalated, and the sheer ubiquity of Trump and Kim’s threats have to some extent re-legitimised the use of nuclear weapons to ‘solve’ conflict rather than deter such “fire and fury” that might bring to an end life as we know it. Indeed, recent research suggests that a limited use of nuclear weapons could disrupt the climate in such a way that would radically alter food production, and in turn lead to global famine.

Trump needs to cut the sass, to scale back his inflammatory and impulsive rants, and to start engaging in the nuclear debate with much greater sensitivity. We want the most peaceful resolution that is now possible, to prevent further escalation of conflict. We do not want stumble into nuclear war, a risk that exists beyond bellicose displays of power. The current hot-threat engagement is not just a security issue, but a massive humanitarian one too. Kim starves his own people in the pursuit of nuclear defence technology. Trump and Kim’s verbally violent exchange is as serious as North Korea’s possession of nuclear weapons. It could have devastating future implications if the stigma of nuclear weapons is not restored. The people of the supposed democracy of the USA and the totalitarian state of North Korea both seem powerless to change the behaviour of their leaders.

However, international attitudes are more progressive. The stigma of nuclear deterrence has not been lost on the majority of nations, 122 of whom endorsed a nuclear weapon ban treaty that seeks to prohibit the development, production, possession, testing, use and threat of use of nuclear weapons. The BAN treaty is likely to enter into force on 20 September 2017, when it opens for signatures at the United Nations in New York. Although no nuclear possessor nation supports this treaty, they understand that the BAN will re-stigmatize nuclear weapons and re-invigorate public debate and action for nuclear abolition.

Our taboos are a greater reflection of our global society and ethics.. What does it say about us at this point in history, if we let the taboo of the unspeakable horror of nuclear warfare disappear? We cannot uninvent the bomb, so we need to rethink and redesign the rules of de-escalation and disarmament, if we are to avoid the fallout of nuclear conflict.

Dr Becky Alexis-Martin is a senior Research Fellow in Nuclear Geography, University of Southampton, UK.

Dr Stephanie Malin is an assistant Professor of Environmental Sociology, Colorado State University, USA.

Dr Kristen Iversen is a professor of English, University of Cincinnati, USA.

Dr Kathleen Sullivan is Director of Hibakusha Stories, New York, USA.

Dr Mwenza Blell is a lecturer in Sociology, University of Cambridge, UK.