Nearly eight decades ago, Congress adopted the National Labor Relations Act (NLRA), and thus instituted a labor-law system empowering a single union to act as the “exclusive” bargaining agent for all the front-line employees in a business, regardless of whether they wanted to join that union or not. As Herbert Hill, the labor director of the NAACP from 1951 to 1977, noted, the NLRA was adopted despite the “intense opposition of the NAACP, the National Urban League, and other Negro interest groups.” Hill explained: “[M]ost of the unions affiliated with the American Federation of Labor [or AFL, a precursor of...