Wall Street Journal writes that a few short months ago, China's economic problems were fueling global panic in markets and drawing unwanted attention and rebuke by the world's largest economies. Now, China's economic challenges have taken a back seat to more pressing geopolitical concerns among finance ministers and central bankers from the Group of 20 largest economies, allowing Beijing to return to the role it prefers: showcasing its growing clout on the world stage. At the conclusion of two days of talks Sunday, the G-20 redoubled calls to use all available policy tools to boost output, wary of mounting headwinds that threaten to tilt the global economy into a low-growth rut. Finance leaders also repeated a commitment to avoid using exchange rates to gain a competitive advantage and vowed to consult closely on exchange-rate policy. International Monetary Fund economists and many G-20 finance chiefs expressed concern that policy makers are relying too heavily on monetary policy to goose growth, calling for more economic restructuring to boost productivity and additional budget stimulus where possible. "Monetary policy alone cannot lead to balanced growth," the G-20 said.