Should American workers fear the economic future? As recently as the early 1990s, many academic and political elites were convinced that the United States was doomed to become a backwater, an economic also-ran. From 1973 to 1995, average labor productivity increased by 1.4 percent a year, a marked decline from the 2.7 percent annual growth rate that drove post-war prosperity from 1948 to 1972. Because Germany, Japan, and a number of other industrial economies had surpassed the United States in productivity growth over that period, it seemed likely that our country would slowly slip behind in the economic league tables.

That’s …