Biological and chemical weapons are banned by treaty and attract less interest by the military than do nuclear and other modern means like cyber, space action and artificial intelligence. The number of nuclear weapons has gone down but there is no sign of their elimination through acceptance of the Treaty Prohibiting Nuclear Weapons (TPNW) or otherwise, nor is there any prospect of early common commitment to ‘non-first use’. Rather, at least the major nuclear-armed states regard their ability to inflict devastating second nuclear strikes as indispensable to deter any first strike and the ‘nuclear posture reviews of the US and Russia retain a good deal of freedom of action. We cannot at present see signs of zero nuclear and must agree with the conclusion that so long as nuclear weapons exist, there remains a risk of use – through misunderstandings or technical errors. We may also conclude that as cyber, space and other new means of struggle have become available, and capable of escalating, rendering conflicts increasingly unpredictable. It becomes implausible that any civilian or military leadership would allow itself to initiate or slide into conflict. It seems likely that they would choose intense competition by means other than force, notably economic and financial.

This chapter describes five “action areas” in which politically achievable changes over the coming two decades could render humankind a lot safer than it is today. For climate change, these include urgent measures for rapid decarbonization, coupled with ramped-up research on technologies for carbon removal and for solar radiation management; new international pacts among small groups of nations for emissions reductions with mutual accountability and incentives; and pre-adaptation measures for dealing effectively with unavoidable harms caused by global warming. For nuclear weapons, these include preparing contingency plans for major or limited nuclear wars, as well as risk-reduction measures than can be implemented today. For pandemics, experts point to four sensible and affordable measures that would greatly reduce the harms of future pandemics. For AI, an immediate challenge will be to prepare for chronic mass unemployment due to rising levels of automation. Finally, the chapter proposes the creation of a new federal agency, the Office for Emerging Biotechnology, to oversee and regulate cutting-edge developments in this field.