I'd guess we have the equivalent of lobbyists in China for US companies doing business there. There would be a lot of "Golden Handshakes" happening to get anything done like zoning or building approvals. I was told that Bordeaux wine at one time, maybe still, was an item of choice in getting some local official to do a thing.
I don't think any US corporations are doing business in Iran or NK today, and probably even in Russia most of what existed has changed or been closed. I think at one point GM sold more vehicles in China than the US, but I could be wrong.