China got a lot of hands/influence in the US Economy; China's the second largest holder of US Gov't debt.
Chinese cyber warfare is another level to most other countries. Couple that with the potential for an untold amount of espionage agents on US soil (much easier for a Chinese agent to blend in in the US than vice versa).
Ain't tryna sound like some tin foil hat motherfukker, but there are real potential avenues for China to cause the US some problems.