The New York Times recently provided a perfect illustration of the dynamics behind the declining marriage rate in its story on Reading, Pa., the city with the highest poverty rate in the country in 2010. It featured the story of Ashley Kelleher, a waitress at an International House of Pancakes, who has been supporting her three children as well as the father of two of them.

“For the past five years, it has been me paying the bills,” she said. Kelleher said she wants to get married someday, but only to a partner who is financially stable. The man she is with now, however, is not.

Social conservatives have looked everywhere for explanations for the decline of heterosexual marriage, everywhere but the American economy. But the research on this issue clearly shows that financially insecure men are less likely to marry.

We can see the relationship between men’s earnings and marriage in the figure below. The figure shows “less money, less marriage,” to quote the authors of a recent report from Pew Social and Demographic Trends. Although the Pew research shows “no significant differences by education or income in the desire to get married,” the less money a male has, the less likely he will actually marry.

For the past 30 years, more and more of America’s income and wealth has been concentrated among America’s rich, leaving less and less for everyone else. With the decline of manufacturing and the decline of unions, men have been particularly hard hit. Half of male workers have experienced stagnating or declining wages over the last 30 years. For Latino and African American men, it is more than half. As a larger share of men are pushed down the earnings scale, their likelihood of marrying declines.

The decline of marriage is a collateral consequence of the growing economic inequality over the last 30 years. If social conservatives want more people to marry, they will need to insist on less economic inequality.

See Reducing poverty and increasing marriage rates among Latinos and African Americans for more on this issue.