Why striking UAW is so public about wanting more – despite big offers

Contract talks between the United Auto Workers union and the three major U.S. automakers are more public than ever this year. It’s part of the union’s high-stakes strategy to win a contract so good that hundreds of thousands of nonunion autoworkers will sit up and take notice.

If the union succeeds, it could convince many of those nonunion workers to join their ranks.

“You kind of want to be with the winner,” says professor Tod Rutherford, who studies labor and the auto industry at Syracuse University.

For decades, unions have...