"When it comes to economies faltering, be careful of what you wish for it affects all economies."
With regards to the Chinese economy, this is not all that bad, vis-a-vis the United States.
For 30+ years we've been hearing about the "largest untapped consumer market" and the benefits to American business, none of which has materialized. The reasons are legion: closed Chinese markets, intellectual and patent piracy, copyright violations, etc. Should the Chinese economy crash, all that would happen is that American corporations would lose money on what have been, for the most part, very bad investments. Free markets have this incredible ability to correct themselves in this way (just ask Ken Lay).
The resulting economic dislocation this would cause would only have relatively short-term effects in this country. The American economy is sufficiently large and diversified so as to survive this kind of hit, and would eventually continue on their merry way after investment capital shifted to more profitable regions or industries. China's economy would not. Once the rotten foundations of Chinese "capitalism" are exposed, American business simply will go back to the tried-and-tested method of investing where they have better prospects of profit (i.e. India, Indonesia, Eastern Europe, South America and, hopefully, HERE).
Continuing to extend MFN status to China, and continuing to pour billions into the Chinese economy is merely the propping up of very bad investments and protecting American corporations from the consequences of their own stupidity.
Yea, we have been propelled into "third world status" with the foreign "super powers" laughing with glee at our economic demise.