The Chinese government is keeping its currency undervalued for a long time now and obviously that is not good for the outside world. A big problem is that there were huge investments in China, a lot of money were sent over there, and if the Chinese markets collapse soon there will be even bigger damage to the US economy (a lot of people think that will happen later this year). It is even worse that these money were not used by the Chinese government to build prosperity, but to ruin its nation, which inevitably will lead to bad consequences.