China's economic bright spots provide a warning

If America's economy begins to deteriorate, people in Ningbo will be among the first to know. The eastern Chinese port, home to 9.6m residents, contains a sprawling industrial district. Its goods are prepared for export, and are shipped abroad via a deepwater harbour, which is one of the world's busiest. The coast of Zhejiang province is dotted with similar entrepà´ts, where thousands of mostly family-owned firms have built up a diverse manufacturing base over the past 40 years. They make everything from textiles and car parts to electronics and machine components. Ningbo is also a city of political importance. Although…