CHANGSHA, China — Even as China prepares to open bullet train service from Beijing to Shanghai by July 1, this nation’s steadily expanding high-speed rail network is being pilloried on a scale rare among Chinese citizens and news media.

Complaints include the system’s high costs and pricey fares, the quality of construction and the allegation of self-dealing by a rail minister who was fired earlier this year on corruption grounds.

But often overlooked, amid all the controversy, are the very real economic benefits that the world’s most advanced fast rail system is bringing to China - and the competitive challenges it poses for the United States and Europe.

Just as building the interstate highway system a half-century ago made modern, national commerce more feasible in the United States, China’s ambitious rail rollout is helping integrate the economy of this sprawling, populous nation - though on a much faster construction timetable and at significantly higher travel speeds than anything envisioned by the Eisenhower administration.

Work crews of as many as 100,000 people per line have built about half of the 10,000-mile network in just six years, in many cases ahead of schedule - including the Beijing-to-Shanghai line that was not originally expected to open until […]