Please elaborate how you plan to identify all these US transactions in real time? I'm not in the US, so please list every single address I've ever been associated with so that I'm not charged more. According to kiklo, it's really easy
I don't know really. And that's the reason why I started this thread and openly asked about that in the OP. To be honest, the technical impossibility of such discrimination (based on IP, or wallet address, or anything else) is the only true reason why the Chinese miners might not raise the fees on a selective basis as an act of revenge even if Trump lives up to his promises and unleashes a trade war with China. All other arguments like irrationality of such actions, coercion by the government, lack of hashing power, etc are weak and can only somewhat limit the fee riot if things get serious. On the other hand, if things do get serious after all, the miners from China could still indiscriminately raise the fees for all...
What consequences would such events have?
A transaction is not associated with an IP address. There is no way to know where a transaction originates, but the Chinese government could identify transactions not originated in China.
If Chinese miners whitelist transactions as kiklo suggests, then only transactions made between Chinese exchanges would be confirmed by Chinese miners. However, all the rest of the miners would still confirm all the rest of the transactions.
If Chinese miners also reject blocks with non-whitelisted addresses, then Bitcoin will die and the Chinese miners and exchanges will go out of business because nobody (including the Chinese) will want to use a currency that is so limited.