One of the seminal moments of presidential debates came in a 1980 tussle between the Republican challenger and the Democrat incumbent. Challenging Jimmy Carter’s record as part of his closing statement , Ronald Reagan asked: “Are you better off than you were four years ago? Is it easier for you to go and buy things in the stores than it was four years ago?” Last Tuesday, in the very first question of her first presidential debate, Kamala Harris was asked that very thing — are Americans better...