In his 1914 novel The World Set Free, Wells describes the “ultimate explosive,” fueled by radioactivity. It enables a single person to “carry about in a handbag an amount of latent energy sufficient to wreck half a city.” These atomic bombs threaten the survival of mankind, as every nation seeks to obtain them—and use them before being attacked. Millions die, the world’s great capitals are destroyed, and civilization nears collapse. But the novel ends on an optimistic note, as fear of a nuclear apocalypse leads to the establishment of world government.