The tech backlash is in full force, and it's rapidly becoming conventional wisdom that social media is polarizing our politics, abusing our attention, misinforming our democracy and damaging our emotional health. But the situation is far more complex than it seems at first glance. Some of these critiques are not well supported by research. And those that are true apply to a particular model of social media, based around surveillant advertising and an endless quest for human attention. What would it mean to build social media expressly designed to strengthen democratic society? Can we imagine an alternative system where public service digital media overcomes some of the thorniest problems of our contemporary online world?