The world faces a perfect storm of existential risk, with a deadly new pandemic, an escalating climate crisis, and the constant threat posed by nuclear weapons. The essential facts and dangers for all of these are long- known, but they have been downplayed or neglected until presenting an immediate threat – by which time it may be too late. We need to have a clear understanding of these risks, but also need to understand the deeper reasons why they have not been properly addressed. To a large extent these lie in the dogmas of military and political elites and in an optimistic preference for short-term results. Civil society and the world community of nations should come together to work for real change, as has already been achieved with the 2020 Treaty for the Prohibition of Nuclear Weapons. They should seek to safeguard the welfare of future generations, giving priority to that interest. The alternative is the growing risk of multiple disasters that could prove terminal.