Women hold up half the sky, as Mao Zedong once declared. Decades later, they don’t hold up much of anything in the halls of Chinese power. In 2012, Liu Yang proved the inverse of Mao’s point, at least as far as China is concerned.

The 34-year-old became the first Chinese woman to orbit the Earth. Her milestone highlighted a less heavenly reality: It is easier for a Chinese woman to circle our planet in outer space than to reach the top rungs of male-dominated Beijing politics.

Expectations that a woman would be included in the Politburo standing committee, China’s most powerful body, came to naught last year. While one did make it to the broader 25-member Politburo, the outcome had China watchers lamenting how the Communist Party remains an old-boys club. As women cool their heels for another 10 years, China has an even bigger gender problem on its hands: a girl shortage.

By 2020, as many as 40 million more men than women will reach adulthood and enter the world’s most competitive mating market. That estimate, which may prove to be conservative, would become a stark economic reality on Xi Jinping’s watch.

China’s cultural preference for sons is partly about economics. Parents can hope to live with their sons in old age, whereas daughters tend to enter other family systems. The testosterone glut is a dangerous side effect of the one-child policy.

Tens of millions of young, ambitious men unable to find girlfriends or wives can’t be good for any economy, never mind one poised to surpass the US. Will the economics of sexual frustration lead to families auctioning off their daughters?

Anyone who has watched the popular Chinese game show One Out of 100, where attractive young women pick from a herd of lonely guys, has to wonder.

Geopolitics is another concern. Officials in Vietnam, Mongolia and Myanmar decry the flow of women to China.

Many pundits are hopeful Xi will be the great reformer the world has been craving.

There are a few promising signs that Xi will address the towering problems that President Hu Jintao ignored. There is talk of shutting the labour camps. Xi’s move to replicate Deng Xiaoping’s 1992 trek through the industrial southeast suggests plans to modernise the economy.

China must stop being the sweatshop of choice for Western manufacturers and start building a more sophisticated demand-driven economy. Just as critical is altering the demographic trajectory.

“It’s critical for China to do everything in its power to redress the deteriorating sex ratio among China’s birth population, even if this means moving toward a two-child policy,” says Valerie Hudson, a co-author of Sex and World Peace. “Regional and even international security is compromised by the fact that approximately 15 percent of its young adult males will not be able to form conventional households.”

China is hardly alone. India’s girl deficit also requires urgent attention.

Some historians are concerned that Asia’s bachelor generation could fuel wars.

It isn’t hard to imagine how the unmet needs of young men might mix with perceptions that China’s economy is rigged for the party elites. Try as he might to intensify internet censorship, Xi will struggle to keep the masses from learning how rich Communist Party members are becoming.

Tens of millions of young, underpaid and unloved men angry at their leaders is in no one’s interest. Xi will have to keep China’s demographic sky from falling.

William Pesek is a Bloomberg columnist

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