This article explains some of the conflict:
https://www.voanews.com/east-asia-pacific/can-taiwans-silico...China’s stance on Taiwan is clear[1] but given Taiwan doesn’t agree, it has remained independent despite what China says. The same was true for Hong Kong until recently, however, so concerns remain.
The US is waking up to realizing that they have a heavy reliance on China for civilian goods and a slight to moderate risk that it might be disrupted or used against them in future.
The worry I suppose is that it might be easier for supply chain-based attacks to weaken US defences, not that we’ve seen anything like this in practice yet due to how easy it is to exploit existing software bugs, for example.
1. https://www.cfr.org/backgrounder/china-taiwan-relations-tens...