Is it ever legal to counterfeit a foregin currency?

Would it be legal to make counterfeit money for certain countries? I believe the U.S. does not recognize copyrights for countries like Iran that we don't have good relations with, would it be legal to print money for countries like Iran or North Korea? I heard that Iran counterfeits a lot of U.S. money and there isn't much we can do about it. I'm just curious if it could work the other way around as well.