Has China Reached Peak Urbanization?

The skylines of some of China's biggest cities sprout from land that was farmed less than a generation ago. For the government, they're a soaring testament to the country's transformation into an urbanized superpower. And despite China's economic slump, there are plenty of bureaucrats who'd like to see the process continue. According to a report last week, local governments are planning to develop more than 3,500 new urban areas in the next few years, with capacity to house 3.4 billion people -- or roughly half of humanity.

It's an audacious set of uncoordinated blueprints, and a good reminder that China's economic planners have yet to find a tool for growth they like more than shoehorning people into newly built cities. But thanks to sweeping demographic and economic changes, they'll need to find one: China's 40-year program of urbanization is reaching its limits.