those currencies to the Peopleâs Bank of China in exchange for yuan at a rate fixed by the bank. When an exporter needs some dollars or euros to buy foreign materials or other imports, it can get them, but the PBOC makes only enough dollars or euros available to pay for the imports and no more; the rest is kept by the bank. The process of absorbing all the surplus dollars entering the Chinese economy, especially after 2002, produced a number of unintended consequences. The first problem was that the PBOC did not just take the surplus dollars, but rather purchased them with newly printed yuan. This meant that as the Fed printed dollars and those dollars ended up in China to purchase goods, the PBOC had to print yuan to soak up the surplus. In effect, China had outsourced its monetary policy to the Fed, and as the Fed printed more, the PBOC also printed more in order to maintain the pegged exchange rate. The second problem was what to do with the newly acquired dollars. The PBOC needed to invest its reserves somewhere, and it needed to earn a reasonable rate of return. Central banks are traditionally ultraconservative in their investment policies, and the PBOC is no exception, preferring highly liquid government securities issued by the United States Treasury. As a result, the Chinese acquired massive quantities of U.S. Treasury obligations as their trade surplus with the United States persisted and grew. By early 2011, Reuters estimated that total Chinese foreign reserves in all currencies were approximately $2.85 trillion, with about $950 billion of that invested in U.S. government obligations of one kind or another. The United States and China were locked in a trillion-dollar financial embrace, essentially a monetary powder keg that could be detonated by either side if the currency wars spiraled out of control.
Rickards, James (2011-11-10). Currency Wars: The Making of the Next Global Crisis (Kindle Locations 1717-1730). Penguin Group. Kindle Edition.