In public, the world's financial chiefs warn of a "two-speed recovery" in which some countries, especially China, are experiencing fast-growing economies while others, notably the United States and much of Europe, are mired in debt and unemployment and barely growing at all.
In private, though, the central bankers and finance ministers of the world's 20 largest economies, gathered in Paris this weekend to confront looming global economic problems, almost all paint a picture of China's surging economy as a powerful black hole whose inward draw is sucking up a huge share of the world's debt, currency reserves, food, commodities and jobs.
Rather than simply surging ahead of the rest of the world, in this view, Beijing's policies are actively holding back other developing countries and jeopardizing wealthier competitors. China's $3-trillion pile of currency reserves, its unwillingness to purchase imports and especially its artificially low currency-exchange rate have sent much of the rest of the world spiralling into instability, in this view.
"That can't go on too long," French Finance Minister Christine Lagarde, the host of the summit, said of China. "As is often the case with big imbalances, a system collapses."
China's growth, propelled by its cheap currency, is overheating dangerously and restricting the ability of other countries to compete and grow, Bank of Canada governor Mark Carney warned in an interview.
"It is absolutely in our interests and the interests of everybody around the G20 table, that China grows at a sustainable pace," he said. "And you can grow too fast in the short term and have it fall back in the medium term. And it's not clear that the policy mix … in China is yet appropriate for medium-term balance."
The International Monetary Fund issued a report Saturday warning of the consequences of a "two-speed recovery."
"The global economic recovery is advancing. However the recovery remains uneven, with downside risks in advanced economies remaining elevated while overheating risks are growing in emerging economies," it said.
But there is much evidence that Beijing is aware of the issue, which could jeopardize its own export markets by preventing consumer recovery in the West.
Chinese authorities surprised observers this weekend by agreeing to a monitoring mechanism designed to detect and prevent future out-of-control imbalances. The mechanism will measure China's currency exchange rates and balance of payments, as well as its levels of public and private debt. It is a step toward setting up rules to forbid countries from accumulating overly large reserves of cash or debt, and triggering another 2008-style crisis.
Most governments - including those of other developing countries - want China to end its policy of pegging its currency, the renminbi, to the U.S. dollar and keeping it artificially low. Brazilian and Indian officials this weekend complained that this is causing a surge of investment in their own, free-floating currencies, pushing their value upward and choking off exports.
Indeed, among the most outspoken critics of China's extreme growth were officials from other formerly poor countries, who said that by having non-floating, artificially low currencies, Asian countries including China were driving currency investors to other emerging-market currencies, pushing their value upward, and preventing them from competing for exports with China.
"All Asian countries need to stop devaluating their currencies, it is a set of responsibilities, it is not just China," Brazilian Finance Minister Guido Mantega said.
The G20 countries, in their communiqué released on Saturday, expressed the problem diplomatically: "While most advanced economies are seeing modest growth and persisting high unemployment, emerging economies are experiencing more robust growth, some with signs of overheating."
But officials warned that the consequences could be grave.
"We all need to keep in mind that we're all going through a pretty amazing transformation of the global economy, it's never happened in this order of magnitude," said Mr. Carney. "Never have so many people been integrated so quickly, never have capital markets been as open as they are now, and this process creates the prospect of lifting billions out of poverty, creating tremendous wealth and improving prosperity for people - but also in that process, creating real risks and vulnerabilities, so we have a collective responsibility to try to manage through this, and not lose those gains."