The Atlantic has a report of research findings showing the decline in manufacturing jobs, held mostly by men, is a cause of a similar decline in blue-collar marriages. Women, it finds, don't experience men as marriageable unless they make more than the women do.
This, along with reduced stigma associated with having children out of wedlock, results in many children being raised in problematic circumstances and poverty. Meanwhile, men who aren't married are more likely to abuse alcohol and prescription opioids, and to suicide.
The article never says so, but the vote for Trump may have been a cry for help by the millions caught up in this trap. His promise to bring back manufacturing jobs must have seemed a lifesaver to these struggling individuals.