Last week, New Zealand became the latest country to declare climate change an emergency. Across the planet, local, regional, and national emergency declarations including those in New Zealand, Japan, and the United Kingdom now represent some 820 million citizens. The United States following suit could tip the scales—and broadcast to the rest of the world, at a crucial moment, that the country is discarding President Donald Trump’s legacy and reclaiming its role as a global citizen. It could also usefully signal to Americans, stunned from four years of whining baby-man antics and upheaval, that the climate crisis is upon us now, not in the distant future.