From nuclear physics we know that energy can be released not only from the fission of heavy nuclei but also from the fusion of light nuclei. Steady progress shows that fusion—one of the few possible options for the future—can be a clean and safe solution for mankind’s long-term energy needs, with minimal environmental impact. A source of energy which would be inexhaustible, inherently safe and environmentally friendly, is this not a marvellous prospect? Nuclear fusion has been the energy source of our Sun and the stars in the universe for billions of years. This process requires temperatures of tens of millions of degrees, so extremely high and foreign to our daily experience as to seem out of reach. Nevertheless, these extremely high tempe...