BY LATE 2015, the nuclear industry had reasons to celebrate for the first time since Japan’s Fukushima disaster in 2011. The United States licensed its first new plant in 20 years, in Tennessee, and Britain took further steps toward building its first nuclear-power station in a generation at Hinkley Point. Japan restarted two of its 43 reactors that had been shut since 2011. And China, which put some of its nuclear building plans on hold after Fukushima, unveiled plans to triple its nuclear capacity by 2020.

But the nuclear landscape is divided in half. In parts of America—by far the world’s biggest user of nuclear power—the talk is of crisis, not celebration; in the north-east, fairly reliable nuclear-power plants are being shut. France, the backbone of Europe’s nuclear industry, plans to reduce the share of nuclear used to generate electricity from 75% to 50% in a decade. Germany intends to shut its remaining eight reactors by 2022.

The places where nuclear is more promising are those where it can find an ingredient almost as essential as uranium: state support. China is the obvious example, and South Korea too has a powerful pro-nuclear lobby. The Watts Bar plant in Tennessee will be in the regulated south, where bureaucrats set the price. The British government has promised sky-high electricity prices to the builders of Hinkley Point.

Yet in places where market forces prevail, nuclear is struggling to survive. The shale revolution in America has caused the price of natural gas there to tumble, making some nuclear-power stations uncompetitive. Subsidies for wind generation in America and Europe are further driving down prices. And though it emits no greenhouse gases, nuclear is often a dirty word among environmentalists. It is rapidly losing the public-relations battle against renewables, even though they need the steady “baseload” power it provides, and the easy alternatives, gas and coal, are dirtier.

This guide shows—for the 30 countries that currently use nuclear power—operational reactors, as well as those under construction and planned, the amount of electricity they produce, and the quantity of uranium they require to do so.