Lianyungang, a booming port city, has China's most extreme gender ratio for children under four: 163 boys for every 100 girls. These numbers don't seem terribly grim, but in ten years, the skewed sex ratio will pose a colossal challenge. By the time those children reach adulthood, their generation will have twenty-four million more men than women.
The prognosis for China's neighbors is no less bleak: Asia now has 163 million females "missing" from its population. Gender imbalance...