BEIJING —By 2020, China will have as many as 30 million single men with virtually no prospect of finding a wife because of the country's staggering gender imbalance. It's expected to create a troubling "bachelor crisis" that will trigger a dizzying array of problems such as a high economic cost to finding a wife, mercenary marriage, human trafficking, intergenerational competition, extramarital affairs, and an increase in sexual diseases and sexual offenses. But that's not even the worst of it.

The most likely outcome may be violence.

In his bestselling bookThe Better Angels of Our NatureAmerican cognitive scientist Steven Pinker wrote that one of the most significant factors in modern society's decline in violence is feminism. Marriage is conducive to social stability. Not only does a married man take responsibility for his offspring, but he also renounces competition with other men for other sexual opportunities. Between 1940s and 1950s in the United States, when people happily married, the homicide rate plummeted. But during the 1960s and 1970s, when people delayed getting married, the murder rate rose. In the African-American community, where the marriage rate is particularly low, the murder rate remains considerably higher too.

A surplus of bachelors is particularly troubling because this demographic is the most unstable population group, representing the major cause of societal violence.

Evoking the demographic changes in the Arab world in his bookThe Future of Freedom, U.S. journalist Fareed Zakaria wrote that "a bulge of restless young men in any country is bad news." Almost all crime in every society is committed by men between the ages of 15 and 25, he noted. "Lock up all young men, one social scientist pointed out, and violent crime will drop by more than 95%."

Historical parallels

Zakaria further wrote that France went through a spike in the youth population just before the French Revolution in 1789. And so did Iran before its revolution in 1979. Even the United States had a youth bulge that peaked in 1968, the year of the country's strongest social protests since the Great Depression.

Likewise, authors Valerie Hudson and Andrea den Boer write in their book A Surplus of Men, a Deficit of Peace, that surplus young adult males will in large measure have an impact on the international and internal security of nations. They pointed out that the methods of offspring sex selection, including active and passive female infanticide, is responsible for China's abnormal birth sex ratio of around 119 boys per 100 girls. The normal ratio ranges from 105 and 107 male births per 100 female births.

As Pinker pointed out, poor men are the societal losers, because when women are scarce, rich men are better positioned to access the marriage market. Pinker writes that these "bare sticks," as Chinese bachelors are called, may form gangs and at worst become a considerable mass threat to local or central authorities.

So what's the solution? In the past, countries conscripted such young men into the military. Even better, he wrote, would be to export "such destructive forces by sending them to other countries' territory, as migrant workers, colonizers or soldiers."

This obviously isn't feasible today.

China's dramatic imbalance is the combined effect of three factors — patriarchal gender preference, the one-child policy that has just been lifted, and the sex selection practice. So to mitigate the situation, all three factors should be eliminated.

The first factor involves societal attitudes, while the latter two are related to governmental policy and regulation. It's much easier to change policy than it is to address social concepts and mores.

Professor Xie Zuoshi has suggested that the social issue could be solved by economic theory — that poor men could share one wife together. He claims his idea is not at all whimsical because in certain remote rural areas, there is already a practice of brothers happily sharing the same wife.

He also says that allowing homosexual men to legally marry would considerably relieve the pressure of China's bachelor crisis.

Xie's suggestions have predictably aroused spirited debate in China and beyond. Whether or not his ideas have merit, his starting point of trying to cope with this impending social crisis with policy won't be enough. It would be akin to quenching a thirst with poison and would not fundamentally solve the problem.