But China's growth is decelerating so rapidly that even with its economy still growing at a near-7 percent annual clip, it is disrupting business plans all over Asia that were counting on even more, said John Anton, director of steel analytics at consulting firm IHS in Washington.
Prices for metallurgical coal used to make steel have dropped nearly 40 percent since 2014, threatening a recently surging Australian coal industry, Anton said. Iron ore has dropped from about $130 to $140 per metric ton to about $50, he said.
Companies made plans years ago that supposed China would be making more than 1 billion tons of steel a year, Anton said — and with production now expected to be about 830 million tons, suppliers are hurting. Falling prices for copper, cement and other commodities reflect slowdowns in Chinese construction as well as manufacturing, he said.
"It was the Buzz Lightyear theory — growth to infinity and beyond," Anton said. "Any plan based on infinite growth is a bad plan."
That matters to the U.S. because Australia is a big trading partner, taking $27 billion of U.S. imports last year and $17 billion through the first nine months of 2015, according to U.S. government data. Australia's imports of U.S. goods are especially important because the U.S. has a trade surplus with Australia.
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The same story is playing out all over the region and even in parts of North and South America.
"It definitely affects Malaysia, Australia and Indonesia,'' said Alaistair Chan, a Sydney-based economist for Moody's Analytics. "Even the more advanced economies are feeling it.''