Scientists have reported a long-awaited nuclear-fusion breakthrough, using lasers to ignite hydrogen-isotope fuel in a self-sustaining burn. But that marks just one step on a long, uncertain road to clean fusion energy. Same-sex marriage in America is now protected by legislation, in a compromise that could provide a template for future culture-war clashes. And the uncertain future of Darjeeling teas.Help us make the show better: take our listener survey at http://economist.com/intelligencesurveyFor full access to print, digital and audio editions of The Economist, subscribe here www.economist.com/intelligenceoffer Hosted on Acast. See acast.com/privacy for more information.