You would think it would be a crime to foment unrest in the USA with foreign money. If not, it should be.
That said, the USA interferes with other countries internal politics all day long, notably in Israel and South America. So turn about is fair play, I suppose.
If Congress gives money to Iran which they use to foment unrest in the US then it is Congress that has funded the unrest.
But we have the authority to stop it also.