From North Carolina to California, many workers are struggling to make it in a stagnant middle class.

Talent has gone awry at the top end of the income ladder, too. Too many bright graduates follow big money into finance, where research suggests they enrich themselves but don’t improve America’s job-creation machine.

Corporate executives have learned that lobbying the federal government can boost their own incomes, while diverting resources from more productive investment. Something has afflicted the little-guy entrepreneurship that historically has served as a ladder to the middle class.

Economists Steven J. Davis and John Haltiwanger concluded this fall that American labor markets became “much less fluid” in recent decades, with far fewer workers hopping to better jobs. Until that fluidity comes back, they wrote, “sustained high employment is unlikely to return.”

Add it all up and you see what’s gone wrong.

Millions of Americans aren’t contributing as much as they could to help the economy grow. When it does grow, those workers are not able to fully share in the spoils.

The median prime-age American male — 25 to 54 years old — earns less today than he did in 1966, adjusted for inflation. After decades of social and economic progress, the median prime-age woman earns less now than she did in 2000. The typical two-parent American family works nearly two more days per week, full time, than it did in 1979 — but earns less per hour, in real dollars. The Federal Reserve calculates that the typical household has less wealth than it did in 1989. Economists Emmanuel Saez and Gabriel Zucman reported recently that 90 percent of U.S. households are worth less today than they were in 1987.

And yet America’s total personal income nearly doubled over the past 25 years, and inflation-adjusted incomes nearly tripled for the top 5 percent of U.S. earners.