The 2017 Nobel Peace Prize has been awarded to the International Campaign to Abolish Nuclear Weapons (ICAN). It came as a surprise to many people who had not heard of the international alliance of over 450 civil society organisations in 101 countries, with its tiny secretariat in Geneva. The award was a tribute to the energy, diplomatic skill, and intellectual prowess that ICAN brought to the establishment of a landmark UN Treaty on the Prohibition of Nuclear Weapons in July this year. 
In establishing the Treaty, more than two thirds of the world’s countries have effectively delegitimised the possession of nuclear weapons as a tool of foreign policy, and brought these weapons of mass destruction in line with the illegality of other abhorrent and indiscriminate weapons, including biological and chemical weapons and cluster bombs.
But the award of the prize was also a response to the increased threat posed by nuclear weapons, not just in the escalation of aggression between the US and North Korea, but also by ongoing hostilities between India and Pakistan, and rising tension between NATO and Russia. In this respect, the prize leaves little room for ICAN to celebrate. We need to work even harder going forward.
An important part of ICAN’s contribution to the establishment of the Treaty was in marshalling the evidence about the risks associated with nuclear weapons, including their effects on the environment and climate.  In the scenario of a limited regional nuclear war between India and Pakistan, for example, in addition to tens of millions of deaths from the direct effects of nuclear explosions, up to two billion people would be put at risk of famine from declines in food production.  A larger scale nuclear war between the US and Russia could induce a nuclear winter that would be incompatible with human civilisation.
But ICAN’s arguments go beyond the morality and dangers of nuclear weapons – they also include clear and cogent arguments against the doctrine of nuclear deterrence itself, and the claim that nuclear weapons help to keep peace and prevent war.
Firstly, there is the point that the doctrine of nuclear deterrence is an unacceptably dangerous gamble. As documented by Chatham House in 2014, the world has already come close to catastrophe on several occasions due to accidents and mistakes.  With over a thousand nuclear warheads currently on high alert across the world, increasing international tension, unstable leaders and new vulnerabilities posed by cyber-warfare, the only way to avoid the accidental, mistaken, irrational, or impulsive use of nuclear weapons is to remove the risk altogether. 
Secondly, this gamble is likely to become even more risky in the face of nuclear proliferation. Indeed, one of the main political impetuses behind the Nuclear Ban Treaty was recognition that the nuclear non-proliferation treaty (NPT) was failing to progress not least because nuclear weapon states, including Britain, continue to cling to the non-credible view that they can prevent proliferation while retaining and upgrading their own nuclear weapons capability.
Thirdly, in an increasingly inter-dependent and globalised world, nuclear weapons are a distraction and hindrance to addressing the threats posed by sea level rise, extreme weather, ocean acidification, biodiversity loss, antimicrobial resistance, global pandemics, cyber-warfare and non-state terrorism. As national security becomes inseparable from transnational security and as international cooperation becomes increasingly vital, the doctrine of nuclear deterrence is not just dangerous but also wrong-headed. 
Finally, although a Nuclear Ban Treaty remains distant from the actual abolition and elimination of nuclear weapons, multilateral disarmament need not be a pipedream of utopian idealists. More and more mainstream politicians, military leaders and academic strategists are discussing the viability of such a goal.  It wouldn’t be easy or quick – and it will be opposed by reckless and psychologically flawed leaders such as Kim Jong-un and Donald Trump, as well as by powerful groups whose interests are vested in war and nuclear weapons.
Despite humankind’s remarkable achievements since the dawn of modernity, we stand on the brink of self-destruction. This is an empirical fact – not a gloomy, prophecy of doom. Ridding the world of our most dangerous weapons of mass destruction should not be viewed as a noble and idealistic aspiration, but as an act of self-preservation.
David McCoy is Professor of Global Public Health at Queen Mary University London, and the former Director of Medact, a UK-based public health charity that is an affiliate of ICAN and the host organisation for ICAN-UK.
1 United Nations, 2017. Treaty on the Prohibition of Nuclear Weapons. http://undocs.org/A/CONF.229/2017/8
2 Robock AL, Oman G. Stenchikov O, Toon C. Bardeen and Turco R, 2007. Climatic consequences of regional nuclear conflicts. Atm. Chem.Phys, 7: 2003-12.
3 Helfand, I, 2013. Nuclear Famine: Two Billion People at Risk—Global Impacts of Limited Nuclear War on Agriculture, Food Supplies, and Human Nutrition. Somerville, MA: IPPNW. Available from: www.ippnw.org/pdf/nuclear-famine-two-billion-at-risk-2013.pdf
4 Lewis P, Aghlani S and Pelopidas B, 2014. Too Close for Comfort: Cases of Near Nuclear Use and Options for Policy, London: Chatham House. https://www.chathamhouse.org/publications/papers/view/199200#sthash.k7C1RdHx.dpuf
5 Kristensen HM and Norris RS, 2017. Status of World Nuclear Forces. Federation of American Scientists https://fas.org/issues/nuclear-weapons/status-world-nuclear-forces/
6 McCoy D, Boulton F and Awan F, 2017. A Safer World: Treating Britain’s harmful dependence on nuclear weapons. London: Medact. https://www.medact.org/2017/resources/reports/safer-world-treating-britains-harmful-dependence-nuclear-weapons/
7 Brixey-Williams S, Ingram P, Pedersen NS, 2017. Meaningful multilateralism: 30 Nuclear Disarmament Proposals for the Next UK Government. http://www.basicint.org/publications/sebastian-brixey-williams-project-leader-paul-ingram-executive-director-nina-sofie