There are 60 million people, almost one in five Americans, living on farms, in hamlets and in small towns across the landscape. For the last quarter century the story of these places has been one of relentless economic decline. This is, of course, not news to the people who live in rural and small-town America, who have been fighting for years to reverse this decline. But now, the nation’s political class is finally noticing. The election of Donald Trump, powered in no small degree by rural voters, has brought the troubles of small-town America to national attention, with an urgent question: What can be done to revive it?Rural America is getting old. The median age is 43, seven years older than city dwellers. Its productivity, defined as output per worker, is lower than urban America’s. Its families have lower incomes. And its share of the population is shrinking: the United States has grown by 75 million people since 1990, but this has mostly occurred in cities and suburbs. Rural areas have lost some 3 million people. Since the 1990s, problems such as crime and opioid abuse, once associated with urban areas, are increasingly rural phenomena.These days, economic growth bypasses rural economies. In the first four years of the recovery after the 2008 recession, counties with fewer than 100,000 people lost 17,500 businesses, according to the Economic Innovation Group. By contrast, counties with more than 1 million residents added, altogether, 99,000 firms. By 2017, the largest metropolitan areas had almost 10 percent more jobs than they did at the start of the financial crisis. Rural areas still had fewer.