New Delhi, Aug. 11 -- IN YINGTAN, a city in the south-eastern province of Jiangxi, China's high-tech future is spilling into its economically backward past. Old-fashioned open-air markets and street-side eateries make it feel like any other rural town in the Chinese interior. An industrial park to the south of the city, packed with companies working on technologies for industrial digitisation, gives off a techie vibe. A national communications laboratory has set up a state-of-the-art research centre nearby.

Over the past decade local officials have helped transform an antiquated copper industry into one that produces high-end components for its new tech denizens. Yingtan's technological wagers are starting to pay off. In 2025 its GDP per...