A s liberals strive for a vision of governance to cure what ails U.S. democracy—and to return a Democrat to the White House—a group of influential thinkers and policymakers has settled on the idea of “abundance.” Popularized by journalists Ezra Klein and Derek Thompson, abundance is an agenda to jump-start the production of public goods that enhance affordability, opportunity, and quality of life. It aims to harness the United States’ culture of innovation by pairing government with businesses,