Any business that does business in or via the USA, including doing business in US Dollars is subject to US sanctions law. The USA frequently punishes foreign businesses which it says has breached its sanctions law. While the media focus is usually on action against UK and EU banks, the simple fact is that successful actions have been brought against, even, individuals buying and selling goods via eBay. So, when the US Treasury says "this is how to design your compliance system," it makes a great deal of sense to pay attention. Yesterday, that's what it said. So pay attention.