The thing I can't understand is that people keep bringing this up as if it's supposed to justify doing it because the US could actually make it work, but then there are still a zillion offshore internet casinos which is strong direct empirical evidence that it does not in fact work.
What matters is if any of their assets are ever denominated in USD, or ever use the international banking system that is also controlled by the US. No other country has that kind of long arm jurisdiction.