In the case of the US, it is precisely the lack of economic ties that is driving its confrontation with Iran. One only has to ask the question: what would happen if relations with Iran were normalised and sanctions lifted? Immediately there would be a scramble for economic position and political influence in Tehran by all the major powers. The US, which has no diplomatic relations with and virtually no trade and investment in Iran, would be starting with a major disadvantage. Confrontation and sanctions, on the other hand, serve to undermine the position of US rivals.
So, the US Government is bashing Iran to prevent the rest of the world from gaining an economic advantage over the US?
Now THERE's a great reason to let your children be killed and crippled!