Time hasn’t been kind to the idea that climate change was humanity’s last problem or that the planet would unite to solve it. A rapid global transition from fossil fuels is, and always has been, impossible. There are several reasons that make it so. Many developing nations never shared the Western elite’s obsession with reducing emissions. Life for most people on earth is still a battle against poverty, hunger and disease. Corruption, lack of jobs and poor education hamper their futures. Tackling global temperatures a century out has never ranked high among the priorities of developing countries’ voters—and without their cooperation, the project is doomed. Geopolitical changes since the 1990s have also limited climate ambitions. Russia, Iran and North Korea have emerged as a destructive and destabilizing axis opposed to global security. Despite their occasional claims to the contrary, none of these nations will support global climate-change-mitigation efforts.