Earlier quoted context omitted.
The US can impose tariffs on trade with the US . If they wanted to impose it on China's oil trade with Saudi or Russia, it would have to be done militarily. And that still leaves the question how to impose a carbon tax on China's domestic coal and oil.
The purpose of carbon tarrifs is not to punish other countries. The purpose of carbon tarrifs is to make foreign dirty-energy-intensive products less competitive, compared to less dirty-energy-intensive ones. Because we already have a way of making domestic dirty-energy-intensive products less competitive. It works great. It's called a domestic carbon tax. They remove the immediate complaint of "If we impose a local…
You're talking about "carbon tarrifs", which I've never heard of, and don't know what they are.