"China is taking advantage of slow global growth and slumping metals prices to warehouse between 200,000 and 300,000 metric tons of copper. Those new purchases will add to a Chinese copper stockpile totaling 1.9 million metric tons in 2011 – equal to the total annual usage of copper in the United States.

What we’re seeing is the early positioning in a resource war that will increasingly define economic growth and national security in the 21st century, as the twin forces of technology and demography accelerate demand for metals and minerals often in short supply."

full story: http://thehill.com/blogs/congress-blog/foreign-policy/321939-chinas-copper-stockpile-americas-metals-deficit