Labor Day is an appropriate moment to reflect on a quiet catastrophe: the collapse, over two generations, of work for American men. During the past half-century, work rates for U.S. males spiraled relentlessly downward. America is now home to a vast army of jobless men who are no longer even looking for work—roughly seven million of them age 25 to 54, the traditional prime of working life.

This is arguably a crisis, but it is hardly ever discussed in the public square. Received wisdom holds that the U.S. is at or near “full employment.” Most readers have probably heard this, perhaps from the vice chairman of the Federal Reserve, who said in a speech last week that “it is a remarkable, and perhaps underappreciated, achievement that the economy has returned to near-full employment in a relatively short time after the Great Recession.”

Near-full employment? In 2015 the work rate (the ratio of employment to population) for American males age 25 to 54 was 84.4%. That’s slightly lower than it had been in 1940, 86.4%, at the tail end of the Great Depression. Benchmarked against 1965, when American men were at genuine full employment, the “male jobs deficit” in 2015 would be nearly 10 million, even after taking into account an older population and more adults in college.

Or look at the fraction of American men age 20 and older without paid work. In the past 50 years it rose to 32% from 19%, and not mainly because of population aging. For prime working-age men, the jobless rate jumped to 15% from 6%. Most of the postwar surge involved voluntary departure from the labor force.

Until roughly the outbreak of World War II, working-age American men fell into basically two categories: either holding a paid job or unemployed. There was no “third way” for able-bodied males. Today there is one: neither working nor seeking work—that is, men who are outside the labor force altogether. Unlike in the past, the U.S. is now evidently rich enough to carry them, after a fashion. The no-work life hardly consigns these men to destitution.

This is at least somewhat true throughout the affluent West, but the U.S. has led the pack. Not even in dysfunctional Greece or “lost generation” Japan has the male flight from work proceeded with such alacrity. The paradox is that Americans—those who do have jobs—are still among the rich world’s hardest-working people. No other developed society puts in such long hours, and at the same time supports such a large share of younger men neither holding jobs nor seeking them.

Who are America’s new cadre of prime-age male unworkers? They tend to be: 1) less educated; 2) never married; 3) native born; and 4) African-American. But those categories intersect in interesting ways. Black married men are more likely to be in the workforce than unmarried whites.