You know, China has other possible responses that don't include invading Taiwan.
What happens if they place sanctions on the US? Suppose they impose a huge tax (tariff?) on goods leaving China, bound for the US?
What if they go bigly and outlaw the export of goods bound for the US? They could easily tell all of the contract manufacturers that they would be free to sell their American-designed wares on the Chinese market to make up for lost revenue coming from US.
I'm in the middle of a project being designed and manufactured outside of Hong Kong. We are about to spend several hundred thousand dollars in tooling for this. In this scenario, they could easily keep their doors open by selling my product in China. Hell, they could sell it for a fraction of what we could - the tooling is already paid for, no freight costs, and no pricy American margins. These guys would come out ahead, I'm sure most others would as well. It's some dirty pool, no doubt and illegal per international laws I'm sure, but haven't we already established that the UN is worthless?
I mentioned before that shutting down the flow of goods from China would have a catastrophic effect on our economy - great depression level stuff. Even a stiff export tax would really kill consumer spending, which is what our whole economy is based on.