Japan’s population is shrinking. For the first time since the government started keeping track more than a century ago, there were fewer than 1 million births last year, as the country’s population fell by more than 300,000 people. The blame has long been put on Japan’s young people, who are accused of not having enough sex, and on women, who, the narrative goes, put their careers before thoughts of getting married and having a family.

But there’s another, simpler explanation for the country’s low birth rate, one that has implications for the U.S.: Japan’s birth rate may be falling because there are fewer good opportunities for young people, and especially men, in the country’s economy. In a country where men are still widely expected to be breadwinners and support families, a lack of good jobs may be creating a class of men who don’t marry and have children because they—and their potential partners—know they can’t afford to.

“The gender stuff is pretty consistent with trends around the world—men are having a harder time,” said Anne Allison, a professor of cultural anthropology at Duke University who edited the recent collection of scholarly essays Japan: The Precarious Future. “The birth rate is down, even the coupling rate is down. And people will say the number-one reason is economic insecurity.”