Kenneth Rogoff of Harvard University, expert on debt crises, and author of "This Time is Different," says China is one of the best examples of the idea that this time is different, with the idea created that somehow China was impervious to the massive build up of debt. The debt is now over 250% of GDP, and this was possible for so long because of the high savings rate of 30% of disposable income and the millions of young migrants moving to cities to work in manufacturing. The growth of shadow banking, opaqueness in decisionmaking, unreliable data, use of local government financing vehicles, the bubble in housing with a large portion of loans tied to the real estate market, all combine to create serious problems that will take a long time to sort out. Rogoff says the crisis in Tianjin with the deadly explosions in the port area, and the government's inability to provide answers to questions from a alarmed public, only added to the uncertainty and loss of credibility. Rogoff says he hopes the trillions of dollars in reserves will provide China with the tools adequate to tackle the debt problems before they spread to other countries....