The answer is simple: America is not a monolith, and it is a free country. It's not a single entity that imports x, exports y, and figures out that it can net o

The answer is simple: America is not a monolith, and it is a free country. It's not a single entity that imports x, exports y, and figures out that it can net out inflows and outflows and just export y-x in the end. It's hundreds of companies, each trying to optimize their own business operations, and ultimately profits. If there are no restrictions from purchasing oil from Russia, or Venezuela, or Libya or whatever, and they find it advantageous to do that, they'll do that. The day the US puts some sanctions, they'll have to scramble and find an alternative. That's the way it is, and it can't be any other way.